Current HIV research

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Effect of compound A on kinetic parameters of HIV-1 enzyme RT. The enzyme RT was incubated in the absence of compound A (), or with five-fold the K i (2.5 M; ) or with ten-fold the K i (5 M; ) for this molecule. Data were analyzed with respect to dTTP (A) or template-primer incorporation (B), according to Materials and Methods. Data represent the average of five independent experiments, and the linewaver-burk plots were generated by SigmaPlot 8.0. The insets (A and B) show the effect of nevirapine on the same kinetic parame- ters.  
We recently described that the chloroxoquinolinic ribonucleoside 6-chloro-1,4-dihydro-4-oxo-1-(beta-D-ribofuranosyl) quinoline-3-carboxylic acid (compound A) inhibits the human immunodeficiency virus type 1 (HIV-1) enzyme reverse transcriptase (RT), and its replication in primary cells. Based on these findings, we performed kinetic studies to investigate the mode of inhibition of compound A and its aglycan analog (compound B). We found that both molecules inhibited RT activity independently of the template/primer used. Nevertheless, compound A was 10-fold more potent than compound B. Compound A inhibited the RNA-dependent DNA polymerase (RDDP) activity of RT with an uncompetitive and a noncompetitive mode of action with respect to dTTP incorporation and to template/primer (TP) uptake, respectively. The kinetic pattern of the inhibition displayed by compound A was probably due to its greater affinity for the ternary complex (RT-TP-dNTP) than the enzyme alone or the binary complex (RT-TP). Besides, by means of molecular modeling, we show that compound A bound on the NNRTI binding pocket of RT. However, our molecule targets such a site by making novel interactions with the enzyme RT, when compared to NNRTIs. These include a hydrogen bridge between the 2'-OH of our compound and the Tyr675 of the enzyme RT's chain B. Therefore, compound A is able to synergize with both a NRTI (AZT-TP) and a NNRTI (efavirenz). Taken together, our results suggest that compound A displays a novel mechanism of action, which may be different from classical NRTIs and NNRTIs.
 
We describe in this paper that the chloroxoquinolinic ribonucleoside 6-chloro-1,4-dihydro-4-oxo-1-(beta-D-ribofuranosyl)-quinoline-3-carboxylic acid (compound A) inhibits the HIV-1 replication in human primary cells. We initially observed that compound A inhibited HIV-1 infection in peripheral blood mononuclear cells (PBMCs) in a dose-dependent manner, resulting in an EC(50) of 1.5 +/- 0.5 microM and in a selective index of 1134. Likewise, compound A blocked HIV-1(BA-L) replication in macrophages in a dose-dependent manner, with an EC(50) equal to 4.98 +/- 0.9 microM. The replication of HIV-1 isolates from subtypes C and F was also inhibited by compound A with the same efficiency. Compound A inhibited an early event of the HIV-1 replicative cycle, since it prevented viral DNA synthesis in PBMCs exposed to HIV-1. Kinetic assays demonstrated that compound A inhibits the HIV-1 enzyme reverse transcriptase (RT) in dose-dependent manner, with a K(I) equal to 0.5 +/- 0.04 microM. Using a panel of HIV-1 isolates harboring NNRTI resistance mutations, we found a low degree of cross-resistance between compound A and clinical available NNRTIs. In addition, compound A exhibited additive effects with the RT inhibitors AZT and nevirapine, and synergized with the protease inhibitor atazanavir. Our results encourage continuous studies about the kinetic impact of compound A towards different catalytic forms of RT enzyme, and suggest that our nucleoside represents a promising molecule for future antiretroviral drug design.
 
Background: Improved viral detections by the real time PCR over the manual assays have been reported by various manufacturers. However, discrepancies and discordance between different platforms targeting the same pathogen have also been observed at different settings. Methods: We used an analytical study design to compare the performance of the Cobas Taqman /Cobas Ampliprep version 2.0 against the standard Amplicor Monitor 1.5 using 200 routine clinical samples, in Abuja- Nigeria. Results: Taqman and Amplicor detected 118/200 (59%) and 83/200 (41.5%) samples respectively. Two of 83 samples (2.4%) undetectable by Cobas Taqman, were detectable by Roche Amplicor, while 5 of 37 samples (13.5%) which were undetectable by Amplicor using Taqman. Among the 81 detectable samples by both assays 4 samples (4.9%) had a log10 difference > 0.5 log copies, while 9 samples (11.1%) showed a wider discrepancy of >1 log10. Bland and Altman's comparison shows no significant difference between the two methods (p=0.2825) and CI-0.06171 to 0.2087. Conclusion: We observed a remarkable improvement in the performance of COBAS AmpliPrep/COBAS TaqMan version 2.0 Assay over Amplicor Monitor version 1.5 in the quantification of HIV1 RNA viral load. Discrepancies of clinical significance, in the viral load between the two platforms were also recorded. The implications of the inability of the automated Taqman 2.0 to detect 2.4% of samples detectable by the Amplicor need to be considered by programs, clinicians and the manufacturers. Periodic evaluation of platforms to detect new circulating HIV subtypes within each locality is also recommended.
 
Organization and features of the 5' untranslated regions of the major HIV-1 transcripts. Structure of the predominant transcript for each open reading frame is shown from among the ~30 alternatively spliced transcripts that are detectable by RT-PCR [66]. Colored lines highlight sequences that comprise the various 5' UTRs. The blue line depicts the first noncoding exon, which is 289 nts in length and is present in all HIV-1 transcripts. The black line denotes the additional 47 nts that are maintained in the unspliced transcript, which is mRNA template for translation to Gag and Gag-Pol protein and is genomic RNA that is packaged into progeny virions. The gray lines represent coding regions and dashed lines denote introns. AUG indicates the translation initiation codon. Also indicated is the number of CUG and AUG codons that are present upstream of actual initiation codon. Translation to Vpu and Env is achieved from the same transcript. The vpu AUG is subject to leaky scanning and scanning may continue until recognition of the downstream env AUG. The unused AUG in this bicistronic transcript is labeled in parenthesis. Depiction of predicted secondary structure of replication motifs is adapted from [7]; the motifs include the trans-activation responsive sequence; primer binding site; dimer initiation site; 5' splice site; and core RNA packaging signal. Alternatively spliced exons, which are depicted in color, may induce variations in the folding of the upstream region, which are not shown. Free energy predictions were calculated using Mfold [51, 87]. Deviations from Kozak consensus are indicated in lowercase letters; underlined nts indicate those most critical for efficient cap-dependent translation initiation.  
Human immunodeficiency virus type 1 (HIV-1) has a small, multifunctional genome that encodes a relatively large and complex proteome. The virus has adopted specialized post-transcriptional control mechanisms to maximize its coding capacity while economically maintaining the information stored in cis-acting replication sequences. The conserved features of the 5' untranslated region of all viral transcripts suggest they are poor substrates for cap-dependent ribosome scanning and provide a compelling rationale for internal initiation of translation. This article summarizes key experimental results of studies that have evaluated HIV-1 translation initiation. A model is discussed in which cap-dependent and cap-independent initiation mechanisms of HIV-1 co-exist to ensure viral protein production in the context of 1) structured replication motifs that inhibit ribosome scanning, and 2) alterations in host translation machinery in response to HIV-1 infection or other cellular stresses. We discuss key issues that remain to be understood and suggest parameters to validate internal initiation activity in HIV-1 and other retroviruses.
 
HIV-associated neurocognitive disorders (HAND) remain prevalent despite effective combined anti-retroviral therapy (cART). Cognitive function has been shown to inversely correlate with decreased synaptic and dendritic density. In this study, macaques inoculated with SIV were examined over a 3-month course of infection to characterize the appearance of the neuronal damage marker 14-3-3 protein in CSF and to determine whether CSF 14-3-3 levels directly reflected synaptic alterations. SIV-infected macaques with 14-3-3 in CSF had significantly lower levels of the pre-synaptic protein synaptophysin in cortical grey matter. Synaptophysin levels were inversely correlated with amount of SIV RNA in the CNS. In contrast, levels of 14-3-3 in CSF did not correspond with either alterations in levels of the post-synaptic protein PSD-95 or viral replication in the brain. These findings suggest that the appearance of 14-3-3 in CSF during asymptomatic infection reflects pre-synaptic damage in SIV-infected macaques and thus may serve as a marker of the early synaptic alterations that underlie HIV-induced neurocognitive impairment.
 
Dendritic cells (DCs), the professional antigen presenting cells, are critical for host immunity by inducing specific immune responses against a broad variety of pathogens. Remarkably the human immunodeficiency virus-1 (HIV-1) subverts DC function leading to spread of the virus. At an early phase of HIV-1 transmission, DCs capture HIV-1 at mucosal surfaces and transmit the virus to T cells in secondary lymphoid tissues. Capture of the virus on DCs takes place via C-type lectins of which the dendritic cell-specific intercellular adhesion molecule-3 (ICAM-3) grabbing nonintegrin (DC-SIGN) is the best studied. DC-SIGN-captured HIV-1 particles accumulate in CD81(+) multivesicular bodies (MVBs) in DCs and are subsequently transmitted to CD4+ T cells resulting in infection of T cells. The viral cell-to-cell transmission takes place at the DC-T cell interface termed the infectious synapse. Recent studies demonstrate that direct infection of DCs contributes to the transmission to T cells at a later phase. Moreover, the infected DCs may function as cellular reservoirs for HIV-1. This review discusses the different processes that govern viral piracy of DCs by HIV-1, emphasizing the intracellular routing of the virus from capture on the cell surface to egress in the infectious synapse.
 
No data are available on the long-term immunovirological outcome of HIV-positive pregnant women experiencing sub-therapeutic antiretroviral drug (ARV) concentrations during pregnancy. The objective of our study was to assess the long-term virological outcome in pregnant women treated with HAART. A prospective, multi-center study enrolled 60 HIV-infected pregnant women stratified into 3 groups according to the response to HAART. Group A, women successfully treated with HAART; Group B, women with confirmed virological failure during HAART; Group C, women successfully treated with HAART during pregnancy for prevention of vertical transmission only. Smoking, alcohol use, low adherence to therapy, and increased viral load at delivery were significantly associated to virological failure at univariate analysis. At multivariate regression analysis, only adherence to therapy was reported as an independent variable related to the virological response (p < 0.001). Virological failure during follow-up was reported in 2 (25.0%) of the 8 women with sub therapeutic Ctrough and in 4 of the 33 (12.1%) women with therapeutic Ctrough (p=0.33). In group C, the viro-immunological set points during follow-up did not differ from those observed before HAART initiation. No significantly increased rate of virological failure after delivery was reported in women with sub-therapeutic ARV concentrations during pregnancy and long-term follow-up. The long-term virological outcome was independently associated to reduced adherence to therapy. Evaluation of the clinical impact of the low plasma ARV concentrations during pregnancy on the long-term virological outcome deserves further larger studies.
 
Interleukin (IL)-18 is a proinflammatory cytokine that plays an important role in both innate and adaptive immune responses against viruses and intracellular pathogens. Increased levels of circulating IL-18 from HIV-1 infected patients have been reported especially in the advanced and late stages of the disease, whereas in the initial stage serum levels of IL-18 were not increased. In contrast, low production of Il-18 was observed in vitro from peripheral blood mononuclear cells (PBMC) of HIV-1 infected patients, and these results were also observed in macaques infected with simian immunodeficiency virus (SIV). In addition, decreased IL-18 production from PBMC was significantly correlated with low production of IL-2. Furthermore, serum levels of IL-18 significantly decreased after highly active antiretroviral therapy. During the early stage of HIV-1 infection there is a decreased production of gamma interferon (IFN), IL-12 and IL-2 as well as not activation of IL-18 production and this leads to inhibition of Th1 immune response, whereas in the advanced stage of the disease, strong activation of IL-18 production along with persistent decreased production of gamma IFN, IL-12 and IL-2 may promote a Th2 immune response, which leads to persistent viral replication. Several studies have shown increased levels of IL-18 in HIV-seronegative subjects with obesity, insulin resistance and type II diabetes. Metabolic disorders, fat redistribution and cardiovascular manifestations are becoming more frequent in HIV-1 infected patients treated with antiretroviral drugs. Consequently, involvement of IL-18 in these disorders has been postulated and demonstrated in patients with lipodistrophy, or with hypertriglyceridemia. Finally, higher serum levels of IL-18 may represent an useful marker in HIV-1 infected patients with metabolic disorders and fat redistribution, as well as a sensitive predictor of cardiovascular complications in treated patients.
 
IL-18 is a pleiotropic and multifunctional proinflammatory cytokine that is often produced in response to a viral infection. The biological activities of the cytokine are tightly controlled by its natural antagonist, IL-18 binding protein (IL-18BP), as well as by activation of caspase-1, which cleaves the precursor form of IL-18 into its biologically mature form. The cytokine plays an important role in both innate and adaptive antiviral immune responses. Depending upon the context, it can promote TH1, TH2 and TH17 responses. Increased serum concentrations of IL-18 and concomitantly decreased concentrations of its natural antagonist have been described in HIV-infected persons as compared to HIV-seronegative healthy subjects. We discuss in this review article how increased biological activities of IL-18 contribute towards immunopathogenesis of AIDS, HIV-associated lipodystrophy syndrome and related metabolic disturbances. While the advent of potent anti-HIV drugs has significantly enhanced life span of HIV-infected patients, it has also increased the number of these patients suffering from metabolic disorders. The cytokine may prove to be a useful target for therapeutic intervention in these patients.
 
Lentiviral based gene therapy may provide a valuable addition to the current anti-HIV arsenal. Many lentiviral vector systems have been described including those based on feline immunodeficiency virus (FIV), human immunodeficiency virus 1 (HIV) and 2 (HIV-2/SIV) as well as replication incompetent, self-inactivating (sin) vs. conditionally replicating (mobilizable) vectors. Lentiviral vectors offer promise in treating HIV-1 infection as they are capable of stably transducing both dividing and nondividing cells, specifically those cells involved in HIV-1 replication and immune restoration: T-cells, hematopoietic stem cells, and dendritic cells. Moreover, some of the HIV-1 and 2 based vectors can be mobilized by wildtype HIV-1 in vivo and spread to those cells targeted by the virus as well as can compete with viral RNA for packaging and access to viral proteins such as Tat and Rev required for viral replication. Finally, lentiviral vectors can be designed to express therapeutic anti-HIV-1 genes, which specifically target various stages of viral replication. Many candidate RNA based anti-HIV-1 genes have been expressed from lentiviral vectors including ribozymes and anti-sense RNA [1]. Recently, small interfering RNAs (siRNAs) have been shown to potently suppress HIV replication [2-6]. This review will focus on the current status of lentiviral vector development and the feasibility of using lentiviral vectors in delivering anti-HIV genes, specifically ribozymes, and siRNAs as a therapeutic approach to employ in conjunction with current anti-retroviral therapies.
 
The study goal is to identify predictors of HIV infection late detection in an European city with increased immigration, and determine the effects of HAART era in HIV infection detection. We used Barcelona city AIDS registry (1987-2006). Late testers were those diagnosed of AIDS defining illness within less than 3 months from time of testing positive for HIV infection. Independent variables were: date of birth, sex, country of origin, HIV transmission category, prison history, city district of residence, AIDS diagnostic disease and HAART era when diagnosed. The statistical methods were based on logistic regression (Odds Ratio, OR and 95% confidence interval, CI). Among the 6186 AIDS patients, 43.9% (n=2741) were late testers. Being a male (OR: 1.57, 95% CI: 1.35-1.83), either < 30 years (OR: 1.21, 95% CI: 1.06-1.38) or > 40 years (OR: 1.20, 95% CI: 1.03-1.40), with heterosexual (OR: 3.07, 95% CI: 2.59-3.63) routes of transmission or men who have sex with men (OR: 2.20, 95% CI: 1.89-2.57) and with Pneumocystis jiroveci pneumoniae (OR: 1.71, 95% CI: 1.47-2.00) or tuberculosis (OR: 1.57, 95% CI: 1.36-1.82) were all independent risk factors for being a late tester. Conversely, injecting drug use (IDU) was associated with early detection (OR: 0.36, 95% CI: 0.33-0.40). Being migrant was associated with late testing only in the univariate analysis. Individuals with the detected factors (male, having any sexual risk behaviour and being > 50 years) should be in the main focus for HIV testing to further ensure continuous decrease in the slope of late detected HIV infections overall.
 
The prevalence of diabetes in the United States is rising. As HIV-infected people live longer, they become more susceptible to chronic diseases such as diabetes. Additionally, some antiretroviral agents have been linked to impaired glucose tolerance and increased diabetes risk. To estimate the burden and trends of diabetes among hospitalized HIV-infected persons in the United States, we used data from the 1994-2004 Nationwide Inpatient Sample, a nationally representative survey of inpatient hospitalizations. Odds ratios (OR) and 95% confidence intervals (CI) were adjusted for demographic and hospital characteristics using logistic regression. Between 1994 and 2004, the rate of hospitalizations with a diabetes code per 100 hospitalizations increased from 3.9 to 8.4 (2.2 fold) among HIV-infected persons. Among HIV-uninfected people, the corresponding rate increased from 12.8 to 17.7 (1.4 fold). Since 1998, the mean age of HIV-infected hospitalized people with a diabetes diagnosis rose from 45 to 66 years and became similar to that of HIV-uninfected people. Compared to 1994-1996, in 2002-2004 the probability of hospitalizations with diabetes increased among both HIV-infected and HIV-uninfected persons (OR, 1.92, 95% CI, 1.79-2.05 and OR, 1.38, 95% CI, 1.36-1.40, respectively). Given the increasing prevalence of diabetes in hospitalized HIV-infected persons, it will be important to monitor the trends closely in addition to the effects of different types of antiretroviral regimens, in order to optimize comprehensive long-term care of HIV-infected persons.
 
Distribution of HIV-1 transmission routes of the 393 patients treated in the Youan AIDS clinic in China from June 2007 to May 2008. Percentage of individuals infected with HIV via various transmission routes are shown as indicated: intravenous drug user (Drug user), commercial blood donation and transfusion (Blood), sexual transmission (Heterosexual, Homosexual, Bisexual), mother-to-child transmission (MTCT), and not identified (Unknown).  
Characteristics of patients as a function of years passed since initial HIV-positive diagnosis in the 393 patients treated in the AIDS clinic in China from June 2007 to May 2008. (A) The distribution of patients initially diagnosed with HIV <1, 1-2, 2-3, 3- 4, 4-5, and >5 years ago. (B) HIV-1 transmission routes (Blood, Drug user, Sexual, and MTCT) from more recent to earlier diagnosed HIV-1 infections. The curves show the percentage of each transmission route in a particular period when initial HIV-1 infection was diagnosed. (C) HIV-1 co-infection with HBV, HCV, and Treponema pallidum (by RPR test) from more recent to earlier diagnosed HIV-1 infections. The curves show the percentage of each co-infection during the period when the initial HIV-1 infection was diagnosed.  
HIV-1 Co-Infection with HBV, HCV and T. pallidum Characteristics No. of Patients % of Total
Current Antiviral Treatment (n=167)
While significant progress has been made since 2003 when a comprehensive treatment, prevention and control program was implemented to combat the HIV/AIDS epidemic in China, new challenges are emerging. There have been limited direct case reports on profiles of HIV/AIDS patients under care at unique clinical settings in China despite significant differences between clinics in this part of the world and those in Western countries. In this report, characteristics of HIV/AIDS patients managed during a 12-month period from June 2007 to May 2008 at a major medical school-affiliated AIDS clinic in the center of Beijing are described. Our data confirm an alarming trend of increased rates of sexual transmission of HIV-1 in recent years and suggest that major improvements are needed for both the type of antiviral treatments being used and post-treatment monitoring of viral load. This information will be useful for the continued progress in the clinical management of HIV/AIDS patients in China.
 
In this article, a retrospective study was conducted based on surveillance of human immunodeficiency virus type-1 positive pregnant women and their children from 2007-2013 in China's Zhejiang Province. HIV counseling and testing, mother and infant characteristics, and outcomes were reported here. This study compares two principal periods, from 2007-2009 and from 2010-2013. Between the two periods, the rate of HIV counseling among pregnant women rose significantly from 84.87% to 99.08% and the rate of HIV testing rose from 80.60% to 98.58% .However, the HIV-1 prevalence among pregnant women increased slightly, from 0.01% to 0.02%. Over 70% of infected women were migrants and half of these HIV-1 positive pregnant women were 20-30 years old. Variations in the characteristics of HIV-1 positive pregnant women were observed over time, the proportion of women employed increased dramatically from 15.03% during 2007-2009 to 31.34% during 2010-2013 and the proportion of women with high school education increased from 0.52% to 6.51% the same time. 32.53% women were identified prior to pregnancy during 2010-2013, this figure was obviously higher than that (3.11%) during 2007-2009. Sexual contact remained the primary route of transmission route over the years which accounting for half of the infected. But women infected by blood transfusion declined noticeably. The proportion of mothers and children with ART had a big increase over time. The overall mother-to-child transmission rate was 7.14%
 
Today, thanks to the HAART, HIV has become a chronic disease. In most cases, HIV positive women are of reproductive age and at present, the vertical transmission rate is around 0.1% for women with an undetectable viral load. So, it is normal that the question of seropositive women's desire to have children is on the table. In this experimental study, 50 HIV-seropositive and 44 seronegative women were interviewed about their desire to have children. Some of the questions asked were: "How many children did you want to have before you got married/at 15 years of age if you aren't married?" "How many children would you like to have today, considering your present situation?". In case of a difference between "before" and "now", we asked them: "What are the reasons for this difference?". This study was performed in Burkina Faso. The positive women tend to desire more children "before" and fewer children "now" than negative women (OR: 1.33; C.I. 95%: 0.86-2; p= 0.19 vs OR: 0.78; C.I. 95%: 0.51-1.21; p= 0.27). 62% of HIV positive women mention multiple reasons directly linked to their seropositivity to explain the difference between "before" and "now". 70% of HIV positive women still want to have children. We have noted that the positive women who still want children are more likely to be younger (p < 0.05 by Two-Sample T tests), in a relationship (p < 0.01 by Chi-Square Test) and to have been diagnosed earlier than the positive women who don't want any children (p=0.01 by Wilcoxon Rank Sum Test). Even if the results of this pilot study are preliminary, they show that HIV positive and negative women have a relatively similar desire for children, even though seropositive women seem to want fewer children than their uninfected counterparts. Most of the reasons which reduce HIV positive women's desire to have children are directly linked to HIV. This is why getting these women informed about materno-fetal transmission risks and existing treatments is really important to give them the opportunity to make a conscious choice.
 
Our goal in this study was to analyze position 22 of the V3 loop associated with co-receptor usage and disease progression in human immunodeficiency virus type 1 (HIV-1) subtype B infection. Bioinformatics approaches were used to compare the amino acid sequence and secondary structure of the V3 loop of the CCR5-tropic virus and CXCR4-tropic virus in HIV-1 subtype B. HIV-1 subtype B V3 amino acid sequence files in the FASTA format were collected from the HIV Sequence Database. The amino acid sequences of different tropism were multiple-aligned with CLUSTAL W program, and the frequencies of the amino acids at each position of the V3 loop sequences of two groups were calculated and sorted in descending order. The secondary structure of the consensus V3 amino acid sequences from CCR5-tropic and CXCR4-tropic viruses were predicted with the APSSP2 method. The amino acids at positions 11, 22, and 25 of V3 were different between the CCR5-tropic virus and CXCR4-tropic virus. The consensus amino acid frequencies were found to be 71.9% S, 66.7% A, and 56.0% D for the CCR5-tropic virus and 50.0% R, 57.1% T, and 26.2% Q for the CXCR4- tropic virus at positions 11, 22, and 25, respectively. There was a strong association between the identity of the residues at position 11, 22, and 25 of the V3 loop amino acid sequence and CD4+ T cell counts of different patients. The change of the residue at position 22 in the R5-tropic or X4-tropic viruses is expected to likely change the secondary structure to be similar to the X4-tropic or R5-tropic viruses. Our study indicates that position 22 of the V3 loop amino acid sequence is significantly associated with viral tropism and disease progression in HIV-1 subtype B.
 
Vaccination of asymptomatic human immunodeficiency virus (HIV)-infected patients with a CD4 cell count ≥ 200/mm³ is strongly suggested prior to travel to a region where yellow fever (YF) is endemic. However, few data describing YF vaccination in such patients are available. In this retrospective observational study of 23 HIV-infected patients, YF antibody titers, CD4 cell counts, and viral loads were measured before and after vaccination. Serologies were performed retrospectively on samples that had been stored as part of routine hospital procedures. Ninety-three percent of patients (13/14) with no baseline immunity, seroconverted after vaccination. Immunogenicity appeared slowly; only 2 of the 5 patients tested within 5 weeks of vaccination had seroconverted. A booster effect was noted in 3 of the 9 patients with baseline immunogenicity. Finally, due to unawareness of his HIV status, one patient was vaccinated and was found later to have a CD4 cell count < 200/mm³.The YF vaccine was well tolerated and no serious adverse events were reported. The impact of vaccination on immunologic and viral parameters was variable. Both decreases (n = 7) and increases (n = 5) in CD4 cell counts were recorded. Viral loads became undetectable in 2 patients and doubled or became positive in 3 patients. Yellow fever vaccination was safe and effective in a large majority of this cohort of stable, HIV-infected patients.
 
Patients characteristics and lipid profile in the two study groups. 
In the current study we investigated the prevalence of the TNF-α 238G/A single nucleotide polymorphism (SNP) of the TNF-α gene in the development of lipodystrophy among HIV-1 infected individuals who had been receiving antiretroviral therapy (ART) in the immunodeficiency clinics of the National AIDS Research Institute (NARI) at Pune, India. We assessed the association of this SNP with the development of lipoatrophy/dyslipidemia and insulin resistance in these patients and measured carotid intima thickening which is a surrogate marker for chronic cardiac morbidity. Our results show that the incidence of the TNF-α 238G/A SNP is ~ two fold higher in patients with lipodystrophy as compared to those without lipodystrophy. Patients with lipodystrophy demonstrated a higher likelihood of the development of metabolic syndrome as evident by increased insulin sensitivity and increased percentage (%) β cell function. Further, a significant increase in left carotid intima thickness was observed in patients with lipodystrophy. Our study validates the association of the TNF-α 238G/A SNP allelic variant with the development of HIV- lipodystrophy via the modulation of TNF-α production, which contributes to dyslipidemia, increased lipolysis, increased insulin resistance, altered differentiation of adipocytes and increased carotid intima thickness. The contribution of genetic determinants such as the TNF-α 238G/A SNP to lipodystrophy, may provide insight into the mechanisms that underlie this disease condition and may be useful in the future for personalized therapy. Additionally, these findings will be useful in monitoring chronic cardiac morbidities among HIV infected individuals who express this SNP.
 
Time to progression of 24 patients with mCRC and HIVinfection.
Summary of Response to Treatment 
Overall survival of 24 patients with mCRC and HIVinfection.
Although FOLFOX4 is considered the standard chemotherapy regimen for colorectal cancer (CRC), few data are available on its results in human immunodeficiency (HIV)-related CRC. The results were analyzed to evaluate feasibility and activity of FOLFOX4 plus highly active antiretroviral therapy (HAART) in metastatic CRC (mCRC) HIV-seropositive patients. From January 2002 to March 2007, 24 patients were selected among the CRC HIV-seropositive patients treated with FOLFOX4 and concomitant HAART within the Italian Cooperative Group on AIDS and Tumors (GICAT). Four median cycles of chemotherapy were administered; the most common severe toxicity was neutropenia (37.5%). An overall response rate of 50% was observed; 4.2% of patients achieved complete response and 45.8% partial response. No opportunistic infections occurred during or immediately after chemotherapy. The median CD4+ count was 380 (range 220-570) at diagnosis. To our knowledge, this is the largest study describing activity and tolerability of FOLFOX4 and HAART, in this setting. FOLFOX4 plus concomitant HAART resulted feasible and active also in HIV-seropositive patients. Moreover, the concomitant use of HAART did not to seem to increase the FOLFOX4 toxicity. This study suggests the good tolerability of the FOLFOX4, making it a reasonable option for combination with HAART.
 
Chronic hepatitis C is frequent and aggressive in HIV-positive patients. Identification of early predictors of response to anti-HCV therapy is needed for a lower rate of response and higher discontinuations, compared to HCV mono-infected subjects. The aim of our study was to evaluate the predictive value of virological response (VR) at week 4-8-12 of Pegylated interferon alpha-2b (PEG-IFN) plus ribavirin (RBV) on sustained virological response (SVR) in HIV-HCV co-infected patients. 100 patients were treated with PEG-IFN (1.5 mcg/Kg/w) plus RBV (> or =10.6 mg/kg/d) and randomized for 24-48 or 48-72 weeks, respectively for genotype 2-3 and 1-4, in case of response (HCV-RNA PCR negativity) at the end of standard therapy (24 weeks for genotype 2-3, 48 weeks for genotype 1-4). Transcription-Mediated Amplification (TMA) assay for HCV-RNA was also applied. 27 patients reached end-of-treatment response (9 genotype 1-4, 18 genotype 2-3), 21 achieved SVR (8 genotype 1-4, 13 genotype 2-3). 35 patients dropped, 15 due to side-effects. SVR was statistically related to lower baseline HCV-RNA and to VR at week 4-8-12, with PPV 64%, 53% and 58%, and NPV 81%, 96% and 88%, respectively. In 27 patients, TMA was performed and confirmed standard PCR, except in two cases of relapse, who were PCR negative but TMA positive at week-12. In conclusion, VR at week 8 showed the highest NPV on SVR (96%). The study of viral kinetics requires further investigations in HIV-positive patients to guarantee a cost-effective therapy and to guide individually the duration of treatment. In this setting, TMA might be useful.
 
Migration of monocytes from the bloodstream across vascular endothelium is required for routine immunological surveillance of tissues and their entry into inflamed sites. Transendothelial migration of monocytes initially involves tethering of cells to the endothelium, followed by loose rolling along the vascular surface, firm adhesion to the endothelium and diapedesis between the tightly apposing endothelial cells. A number of adhesion molecules are involved in this process. Monocyte rolling can be mediated by selectins and their ligands, or alpha(4)beta(1) integrin interacting with endothelial VCAM-1. On the apical surface of the endothelial cell, bound chemokines (eg. MCP-1, MIP-1alpha/beta) can activate leukocyte beta(2) integrins for tight adhesion to ICAM-1 and -2. Diapedesis by monocytes occurs through interaction between PECAM-1 on both the monocyte and the endothelial cells, followed by similar homophilic adhesion via CD99. After penetration of the endothelial basement membrane, monocytes migrate through the extracellular matrix of the tissues where they may differentiate into tissue macrophages and/or migrate to sites of inflammation. Additionally, monocytes in the tissues may traffic to the lymphatics or back into the bloodstream, both of which involve basal to apical (reverse) transendothelial migration, possibly mediated by tissue factor and p-glycoprotein. Monocyte trafficking is of current interest in studies of the pathogenesis of HIV-infection, including establishment of viral reservoirs in tissues and sanctuary sites and the development of HIV-related dementia. This review provides insights into the most recent studies on the process of monocyte migration across the vascular endothelium, and changes in migration that can occur during HIV-infection.
 
Epidemiological and Clinical Characteristics of HIV-1+ Patients
C-C chemokine receptor type 5 (CCR5) is known for its role as a co-receptor for HIV-1 infection. Some individuals possess a 32 bp deletion, known as Delta-32 allele which has been reported to confer resistance to HIV-1 infection. In order to estimate the distribution of Delta-32 allele of CCR5 gene, 1034 mestizo individuals from the Northwest of Mexico, including 385 HIV-1-infected individuals, 472 healthy controls and 177 uninfected female sex workers; were examined by allele-specific PCR. There was no statistically significant difference in the frequency of Delta-32 allele between HIV-1 positive and healthy individuals (OR= 1.1, p= 0.6). However, we found a significantly reduced prevalence of CCR5 Delta-32 heterozygous genotype in female patients (OR= 0.084, 95% CI= 0.011 - 0.630, p= 0.002), as well as in allele frequency, compared to male patients. Furthermore, we observed an inverse relationship between allele frequency and the risk of HIV-1 transmission and AIDS progression among female healthy controls, sex workers and HIV-1 infected groups. Our findings support previous data showing Delta-32 as a genetic protective factor against HIV-1 infection in Mexican women, as well as in women from other populations.
 
The antimicrobial peptide LL-37 is the only cathelicidin that has been described in humans. LL-37 exerts chemotactic, immunomodulatory and angiogenic effects; activities that are mediated through binding to the formyl peptide receptor like (FPRL)-1 receptor. Agonistic ligation of FPRL-1 can also induce down-regulation of HIV-1 chemokine receptors and reduce susceptibility to HIV-1 infection in vitro. Therefore, we have evaluated the capacity of LL-37 to inhibit HIV-1 infection in vitro. Here we demonstrate that LL-37 inhibits HIV-1 replication in PBMC, including primary CD4(+) T cells. This inhibition was readily reproduced using various HIV-1 isolates without detectable changes in the target cell expression of HIV-1 chemokine receptors. Accordingly, the HIV-1 inhibitory effect was shown to be independent of FPRL-1 signalling. Given the epithelial expression of LL-37, it may contribute to the local protection against HIV-1 infection.
 
To promote the initiation of reverse transcription, the HIV-1 virus uses a host tRNA as a primer, tRNA(3Lys). The annealing of tRNA(3Lys) to the viral RNA requires the breaking of the 3D structure of the tRNA and RNA rearrangements, to form a stable initiation complex recognised by the reverse transcriptase. The annealing is mediated by a viral factor, the nucleocapsid protein. This protein has been studied for a long while to define the role of its different sub-domains and their mode of action. Only recently, a consensus view seems to emerge. The structure of the initiation complex, is still discussed. The goal of this review is to clarify what is known about the formation and the structure of the tRNA/viral RNA complex and the role of the nucleocapsid protein from a structural point of view.
 
Raltegravir (RAL) has been shown to be virologically effective in both treatment naive and triple class resistant patients. A more favourable metabolic profile associated with RAL in comparison with other antiretroviral drugs has also been observed. The aim of this study was to investigate the molecular mechanisms that could explain the lack of toxicity of this drug in metabolism. Thus, the effects of RAL on adipogenesis and adipocyte metabolism were analyzed using 3T3-L1 cells, a very adequate and convenient cell culture model for the investigation of adipose differentiation and metabolism. The effects of RAL on adipogenesis were evaluated by the Oil Red O staining after 8 days of induction of differentiation. Several adipogenic genes (C/EBP, PPAR, Pref-1 and AP2) were analyzed by real time PCR. Fully differentiated adipocytes were also incubated with RAL for 24 hours and glucose utilization, lactate production and glycerol release were analyzed. Thus, minimal effects of RAL on murine adipocyte differentiation were observed. Basal glucose uptake and lactate production were not affected by RAL at any of the concentrations used. No effects were also found on the percentage of glucose that is metabolized to lactate. Lipolysis was only slightly inhibited by Raltegravir (-10%) at the highest concentration used (50 µM), while no effects were observed with lower doses. Our results suggest that the absence of significant actions of RAL on adipogenesis and glucose and lipid metabolism in adipocytes could explain, at least in part, the neutral metabolic effects of RAL in clinical studies.
 
Low levels of plasma viremia (below 50 copies/ml of HIV-1 RNA) can be detected in the majority of HIV+ subjects successfully treated with HAART. Aim of our study was to evaluate the impact of different antiretroviral regimens on this residual viremia and on proviral HIV-1 DNA in HAART-treated subjects with plasma HIV RNA <400 cp/ml and no history of virological failure. To this purpose, a cross-sectional analysis of 319 HIV-positive patients on HAART with plasma HIV RNA <400 cp/ml was performed. Subjects had been on HAART for a median of 3.6 years: the current regimen included two nucleoside reverse transcriptase inhibitors (NRTIs) plus a protease inhibitor (PI) in 104 (32.6%) cases, of which 73 treated with a boosted PI; two NRTIs plus a non-NRTI (NNRTI) were prescribed in 166 (52.2%) cases, and NRTIs-only in 49 cases (15.4%). Patients treated with PI had the lowest nadir CD4 cell count (237+191 cells/microl) compared to patients treated with NNRTI (384+192 cells/microl) or NRTIs-only (387+222 cells/microl). Cell-associated HIV-1 DNA was measured in 231 subjects. Residual viremia was measured in 238 subjects with plasma HIV-1 RNA levels < 50 copies/ml. Multivariate analysis showed that the use of NNRTI was independently associated to low levels of residual viremia and high levels of HIV-1DNA, whereas the use of PI was independently associated to low levels of HIV-1 DNA. The better virological performance of NNRTI in terms of low residual viremia is consistent with specific literature data, whereas the greater impact of PI on the viral reservoirs is noteworthy and needs further investigations.
 
Characteristics of Study Subjects
A portion of the gag gene cDNA for p24 protein from 30 Indian HIV-1 proviral DNA were amplified by PCR and sequenced. Phylogenetic analysis with reference samples of A1, A2, B, C, D, F1, F2, G, H, J, K, N and O sub types revealed that 29 test samples aligned with subtype C reference strain while 1 matched with HIV-1 subtype A. Multiple alignment of predicted amino acid sequence of the Indian test samples and reference C subtype of HIV-1 samples from other countries indicated a molecular signature by way of rigid conservation of the amino acid 'S' at position 41 of the gag p24 protein in all Indian HIV-1 samples analyzed in this study as opposed to 'T' in the same position in C subtype sequences from other parts of the world. A phylogenetic analysis and visualization of the resulting tree in radial position showed distinct clubbing of all Indian C subtypes and formation of a cluster when compared to C subtype sequences from other countries with a single Chinese sample as an exception which was found in the Indian cluster. The use of a portion of p24 gene sequence as tool for sub typing as well as phylogenetic grouping with special reference to its geographical location is discussed.
 
Since recent observations demonstrated that extended resistance to protease inhibitors, nucleosidic and non - nucleosidic retrotranscriptase inhibitors (PI, NRTI, NNRTI) is a marker of disease progression and death, it is a matter of the greatest importance that experienced human immunodeficiency virus (HIV) - infected patients with limited therapeutic options receive a suppressive therapy pending the availability of at least two new antiretroviral drugs. Aim of the present study is to evaluate if the GSS score, calculated by analyzing the resistance to historical antiretroviral drugs and drug classes, is still relevant since several new potent drugs and drug classes entered the current clinical use. Taking into account patients without suppression of HIV replication for ≥ 6 months from October 2008 and October 2009, we analyzed viroimmunological and resistance data of 38 outpatients starting their last antiretroviral regimen including at least one of the following: maraviroc, enfuvirtide, raltegravir, etravirine, darunavir/ritonavir or tipranavir/ritonavir. Mutations present in all available genotypic resistance tests were recorded for each patient and then correlated to GSS value, assessed using the last genotypic ribonucleic acid (RNA) resistance test. GSS was studied as predictor of virological treatment outcome by univariate and multivariate logistic regression. At 48 weeks, undetectable viral load was obtained in 80% of patients without difference between GSS classes (HIV-RNA median < 50 copies/ml); 95.8% of patients with baseline HIV-RNA < 50,000 copies/ml obtained virological suppression (p=0.003). 48 weeks CD4+ median value was 412 cells/μl considering GSS1 and 300 cells/μl for combined GSS2 and GSS3 scores. Data also showed a > 60% recurrence of specific mutations for NRTI: M41L, M184IV, L210W, T215FY, K219EQ and 75% for D67N. K103N and Y181CIV mutations for NNRTI persisted in 35% of cases and their prevalence incresed in parallel with the number of GRTs. About 60% of tests reported L10FIRVC, M36ILV, M46IL, I54VLAMTS, V82AFTSLI, and L90M mutations in the protease region. 63P mutation was found in a total number of GRTs close to 80%. This percentages, when correlated to GSS, revealed a distinct pattern for most mutations, that showed a greater prevalence for GSS = 2. Conversely, only NNRTI 181CIV and NRTI 210W showed larger numbers in GSS1 and GSS3. Single drugs belonging to new antiretroviral classes did not correlate to viroimmunological success for any GSS. High frequency and recurrence over GRTs for specific mutations confirm their key role following the exposure to ARVs classes. A baseline HIV-RNA < 50,000 cp/ml is a predictor of therapeutic success and a carefully selected HAART based upon the evaluation of GRTs can favorably influence the immunovirologic response.
 
To evaluate long-term outcomes in patients maintaining a nevirapine (NVP)-based regimen. Retrospective, multicenter, cohort study including patients currently receiving an NVP regimen that had been started at least 5 years previously. Demographic, clinical, and analytical variables were recorded. Median follow-up was 8.9 (5.7-11.3) years. Baseline characteristics: 74% men, 47 years old, 36% drug users, 40% AIDS, 40% HCV+, 51.4% detectable HIV-1 viral load, CD4 count 395 (4-1,421)/μL, 19% CD4 < 200/μL, 27% ALT grade 1-2, 36% AST grade 1-2. Thirty percent ART-naive, 83%received NVP associated with 2 nucleoside analogues during the study period, and 17% a protease inhibitor. A significant improvement was observed in general health status markers, including hemoglobin, platelets, and albumin, regardless of HCV coinfection. CD4 cell gain was +218 and +322/μL after 6 and 9 years, respectively (+321 and +391 in naive patients). Triglycerides significantly decreased in pretreated patients, whereas the percentage of patients with HDLc < 1.03 mmol/L and LDL-c > 3.37 mmol/L significantly decreased in a subsample with available values. A significant decrease in transaminases, alkaline phosphatase, and Fib4 score was observed, mainly in HCV+ and ARV-naive patients. In patients who tolerate NVP therapy, (even those with HCV coinfection), long term benefits may be significant in terms of a progressive improvement in general health status markers and CD4 response, a favorable lipid profile, and good liver tolerability.
 
Background: Single nucleotide polymorphism of the hepatic cytochrome P450 isoenzyme 2B6 (CYP2B6) gene is a cause of variation in plasma efavirenz (EFV) concentrations. We aimed to determine the allelic distribution of CYP2B6 gene, plasma levels of EFV, the prevalence of clinical depression, and their correlations in northern Thai population. Methods: This was a cross-sectional study of HIV-infected patients on EFV-containing antiretroviral regimens for ≥48 weeks. A single blood specimen was collected for determination of the mid-dose plasma EFV concentration and CYP2B6- 516G > T polymorphism. The presence and severity of depression were assessed. Results: One hundred patients were enrolled [mean age (±SD) was 41.81±8.44 years, mean CD4 lymphocyte count 462±193 cells/ul]. The genotype CYP2B6-516 guanine/guanine (G/G), guanine/thymidine (G/T), and T/T were found in 49%, 37%, and 14% of patients, respectively. The allele frequency of CYP2B6-516 G to T replacement was 32.5%. The median plasma EFV concentration was 2,616 ng/mL (IQR 1,851-3,742); 79% had EFV plasma concentrations from 1,000 to 4,000 ng/mL. The mean EFV concentrations for those with G/G, G/T and T/T genotypes were 2,082±630, 3,166±1,074, and 11,196±6,265 ng/mL, respectively (p < 0.01). CYP2B6-516G > T polymorphism was the only factor associated with high plasma EFV levels. Nineteen patients had depression; 13 of 18 (72%) with mild and one with major depression had normal plasma EFV level. A weak correlation between plasma EFV concentrations and depression scores was observed (p=0.009, R2=0.059). Conclusions: The prevalence of CYP2B6-516G > T polymorphism in northern Thai population is high and strongly associated with inter-individual drug levels variation.
 
AIDS-Defining Conditions Prior to or at the Moment of Starting HAART 
Baseline Characteristics: Immigrant Cohort by Region of Origin 
currently, 12% of the Spanish population is foreign-born, and a third of newly diagnosed HIV-infected patients are immigrants. We determined whether being an immigrant was associated with a poorer response to antiretroviral treatment. historical multicenter cohort study of naïve patients starting HAART. The primary endpoint was time to treatment failure (TTF) defined as virological failure (VF), death, opportunistic disease, treatment discontinuation (D/C), or missing patient. Secondary endpoints were TTF expressed as observed data (TFO; censoring missing patients) and time to virological failure (TVF; censoring missing patients and D/C not due to VF). A multivariate analysis was performed to control for confounders. a total of 1090 treatment-naïve HIV-infected patients (387 immigrants and 703 autochthonous) from 33 hospitals were included. Most immigrants were from Sub-Saharan Africa (28.3%) or South-Central America/Caribbean (31%). Immigrants were significantly younger (34 y vs. 39 y), more frequently female (37.5% vs. 24.6%), with less HCV coinfection than autochthonous patients (7% vs. 31.3%). There were no differences in baseline viral load (4.95 Log(10) vs. 4.98 Log(10)), CD4 lymphocyte count (193.5/µL vs. 201.5/µL), late initiation of HAART (56.4% vs. 56.0%), or antiretrovirals used. Cox-regression analysis (HR; 95%CI) did not show differences in TTF (0.89; 0.66-1.20), TFO (0.95; 0.66-1.36), or TVF (1.00; 0.57-1.78) between immigrants and autochthonous patients. Losses to follow-up were more frequent among immigrants (17.8% vs. 12.1; p=0.009). Sub-Saharan African patients and immigrant females had a significantly shorter TTF. the response to HAART among immigrant patients was similar to that of autochthonous patients, although they had a higher rate of losses to follow-up. Sub-Saharan Africans and immigrant females may need particular measures to avoid barriers hindering antiviral efficacy.
 
Polymorphisms of chemokines and chemokine-receptors genes have been shown to influence the rate of progression to AIDS; however, their influence on response to HAART remains unclear. We investigated the frequency of the SDF-1-3'A, CCR2-64I, CCR5-D32 and CCR5-Promoter-59029-A/G polymorphisms in Brazilian HIV-1-infected and uninfected individuals and their influence on CD4+ T-cell evolution HIV-1 infected individuals before and during HAART. Polymorphism detection was done in a transversal study of 200 HIV-1-infected and 82 uninfected individuals. The rate of CD4+ T cell increase or decrease was studied in a cohort of 155 HIV-1 infected individuals on pre and post-HAART. Polymorphisms were determined by PCR associated with RFLP. The rate of CD4+ T-cell decline or increase was also determined. HIV-1 infected and uninfected subjects showed, respectively, frequencies of 0.193 and 0.220 for SDF-1-3'A, of 0.140 and 0.110 for CCR2-V64I, of 0.038 and 0.055 for CCR5-D32, and of 0.442 and 0.390 for CCR5-P-59029-A/G. HIV-1-infected subjects carrying one, two or three of these four polymorphisms showed better CD4+ T-cell recovery than HIV-1-infected subjects carrying the four wild-type alleles (+2.7, +1.6, +3.5, and -0.9 lymphocytes/microl/month, respectively). Regression logistic analysis showed that the CCR5-D32/CCR2-V64I association was predictor of positive CD4+ T cell slope after HAART. The distribution of polymorphisms did not differ between HIV-1-infected and uninfected individuals, but differed from more homogenous ethnic groups probably reflecting the miscegenation of the Brazilian population. We add further evidence of the role of these polymorphisms by showing that the CD4 gain was influenced by carriage of one or more of the polymorphisms studied here. These results highlight the possibility that these genetic traits can be useful to identify patients at risk for faster progression to AIDS or therapeutic failure.
 
Model for the regulation of Tat-TAR binding by acetylation and its implications for the in vivo trans-activation mechanism. PIC is the transcription preinitiation complex before or after hypophosphorylation of the RNAPII CTD by CDK7/TFIIH. The doublesided arrow shows the release the Tat-CycT1-CDK9 complex from TAR RNA. Newly synthesized TAR RNA is in blue.  
Viral and Cellular Proteins Involved in HIV-1 TAR RNA Functions
Role of TAR RNA and its interacting cellular proteins in the regulation of HIV-1 translation.  
HIV-1 TAR RNA is the binding site of the viral protein Tat, the trans-activator of the HIV-1 LTR. It is present at the 5' end of all HIV-1 spliced and unspliced mRNAs in the nucleus as well as in the cytoplasm. It has a highly folded stem-bulge-loop structure, which also binds cellular proteins to form ribonucleoprotein complexes. The Tat-Cyclin T1-CDK9 complex is the main component in the trans-activation of HIV-1 and its affinity for TAR is regulated through Tat acetylation by histone acetyl transferases. Recent studies show that this complex is able to recruit other cellular partners to mediate efficient transcriptional elongation. TRBP, PKR and La bind directly to the TAR RNA structure and influence translation of HIV-1 in either positive or negative manners. Some mutations in TAR RNA severely impair HIV-1 trans-activation, translation and viral production, showing its functional importance. The overexpression or suppression of several TAR RNA-binding proteins has a strong impact on viral replication pointing out their major role in the viral life cycle. TAR RNA has been the target of drug development to inhibit viral replication. Recent data using small molecules or RNA-based technologies show that acting on the TAR RNA or on its viral and cellular binding factors effectively decreases virion production.
 
We designed a multicenter cross-sectional study to describe the epidemiological characteristics of the HIV-1-infected population aged 70 years or more in our setting. 179 individuals from eight university hospitals in Barcelona, Spain, were included, representing 1.5% of HIV-1 infected subjects followed during 2008. Most subjects were male (76%) and had acquired HIV infection through sexual intercourse (87%); 69% had been diagnosed with HIV-1 after their sixties. The CD4 cell counts at HIV-1 diagnosis were < 200 cells/mm(3) in 52% of individuals, whereas this was only seen in 34% of subjects from a published cohort including younger HIV- infected adults from the same setting [1]. Most of our patients were on HAART, had undetectable HIV-1 viremia and the most recent median CD4 cell counts were >or= 350 cells/mm(3). 154 subjects had at least one comorbid condition, including dyslipidemia (54%), hypertension (36%), hyperglycemia or diabetes (30%), cardiovascular disease (23%), chronic renal failure (18%), history of neoplasia (17%) and cognitive impairment (11%). Lipodystrophy was reported in 58% of individuals. Rates of hypercholesterolemia, diabetes and cancer were higher than those reported in unselected local population (28%, 17% and 7%, respectively). The study participants were taking an average of 2.97 drugs (range 1-10) other than antiretrovirals. In conclusion, the elder population infected with HIV-1 is likely being diagnosed late and at lower CD4+ counts and is frequently affected by comorbidities and co-medication. Based on our findings, we suggest some recommendations regarding the management of this growing population.
 
Patient Baseline Demographics and Disease Characteristics 
Patient Disposition and Week 96 Virologic Response Rates 
Adverse Events, Serious Adverse Events and Grade ≥3 Laboratory Abnormalities 
Objectives: Increasing life expectancy of HIV-1-infected patients raises interest in how trial results apply to older patients. This post-hoc analysis evaluated potential differences in efficacy and safety in older (≥50 years) versus younger (<50 years) patients in the ECHO and THRIVE trials over 96 weeks. Methods: HIV-infected, treatment-naïve adults were randomized to receive rilpivirine (RPV) or efavirenz (EFV), plus a background regimen. Virologic response rates (FDA snapshot analysis; HIV-1 RNA <50 copies/mL) were assessed at Week 96. Total-body bone mineral density was evaluated at baseline and Week 96 by dual-energy X-ray absorptiometry scans. Serum concentrations of 25-hydroxy vitamin D (ECHO trial only) were also measured at baseline, Week 24 and Week 48. Results: 1368 patients were treated. At Week 96, virologic response rates were similar between older (77%) and younger (76%) RPV-treated patients and numerically higher in older (84%) versus younger (76%) EFV-treated patients. No clinically relevant age-related differences were observed in immunologic responses. Small differences were noted in older versus younger patients in adverse events (higher rates of depression, insomnia, and rash in older EFV-treated patients), laboratory abnormalities (increased low-density lipoprotein cholesterol and hyperglycemia in older EFV-treated patients and increased amylase in older patients across treatments), bone mineral density (larger decreases in older patients across treatments), and progression to severe vitamin D deficiency (greater in older versus younger EFV-treated patients). Conclusion: Efficacy and safety outcomes were generally similar in older versus younger patients in the ECHO and THRIVE trials.
 
The disease profile of treatment-experienced HIV-1 patients (TEPs) looks different today compared with that of 5 years ago. Because less highly treated DUET patients may more closely resemble today's TEPs, we conducted a post hoc efficacy and safety analysis of the pooled 96-week DUET data stratified by level of treatment experience. TEPs with HIV-1 were randomised to etravirine (ETR) 200mg twice daily (bid) or placebo bid with a background regimen for 48 weeks (plus optional 48-week extension). TEPs were categorized using 10 demographic and disease characteristics that in prior studies of treatment-experienced subjects had been associated with virologic response; patients meeting ≥5 criteria were categorized as less TEP. 183 patients (men, 87.4%) who received ETR were less TEP and 413 patients (men, 91.0%) were more TEP. At baseline, more TEPs had more advanced disease, more previous antiretroviral (ARV) exposures and fewer options for active ARVs. At Week 96, for patients receiving ETR, response rates for the less TEP group and more TEP group were 68.3% and 52.8%, respectively. Incidence of adverse events (AEs) was similar between groups. A greater proportion of nonresponders in the more TEP group discontinued due to AEs (9.0% vs 5.5%) and virologic failure (18.9% vs 5.5%) compared with the less TEP group. Less TEPs had higher virologic response rates with ETR compared with more TEPs. Because the less TEP population from DUET more closely resembles TEPs with HIV-1 today, data from this subgroup may provide valuable information for real-life treatment decisions.
 
Long-term potent activity of antiretrovirals is essential for HIV-1-infected, treatment-experienced patients. TITAN (TMC114/r In Treatment-experienced pAtients Naive to lopinavir) compared Week-96 efficacy and safety of darunavir/ritonavir (DRV/r) versus lopinavir/ritonavir (LPV/r). Treatment-experienced, LPV-naive, HIV-1-infected patients were randomised to DRV/r 600/100 mg bid or LPV/r 400/100 mg bid plus optimised background regimen (≥ 2 NRTIs/NNRTIs). 595 patients were enrolled (mean baseline HIV-1 RNA: 4.30 log10 copies/mL; median CD4 count: 232 cells/mm3). At Week 96, more DRV/r than LPV/r patients achieved HIV-1 RNA < 400 copies/mL (66.8% versus 58.9% [intent-to-treat (ITT)/time-to-loss of virological response (TLOVR)], estimated difference 8.7%, 95% confidence interval [CI]: 0.7-16.7), demonstrating the primary endpoint of non-inferiority of DRV/r (p < 0.001); the difference in response was statistically significant (p = 0.034). For the secondary efficacy parameter (HIV-1 RNA < 50 copies/mL) at Week 96, response to DRV/r was 60.4% versus 55.2% for LPV/r (ITT-TLOVR), estimated difference 5.8%, 95% CI: -2.3-13.9. Virological failure (VF; HIV-1 RNA > 400 copies/mL) with DRV/r (13.8%) was nearly half that with LPV/r (25.6%). Discontinuations due to adverse events were 8.1% for both DRV/r and LPV/r. Treatment-related grade 2-4 diarrhoea was 8.1% (DRV/r) versus 15.2% (LPV/r). Increases in triglycerides and total cholesterol were less pronounced with DRV/r. At 96 weeks, noninferiority (HIV-1 RNA < 400 copies/mL) of DRV/r over LPV/r was maintained; the difference in response was statistically significant. VF rate and treatment-related grade 2-4 diarrhoea were lower with DRV/r versus LPV/r.
 
The map of Armenia. AM-Armenia, AZ-Azerbaijan, IR-Iran. 
There is scarce information about the molecular epidemiology of HIV-infection in Armenia (former USSR). The objective of this work was to estimate the distribution of HIV-1 subtypes in this country and get any information about HIV drug resistance in naïve patients. A joint study involving 78 patients was carried out in Yerevan, Armenia and Moscow, Russia in 2009-2013. The cohort studied included mostly IDUs (28.2%) and heterosexuals (69.2%). The phylogenetic analyses based on population sequencing of partial pol gene found subtype A1 being the most prevalent (92.3%), followed by subtype B (3.9%). The HIV-1 tropism inferred from env V3-loop sequences was determined in 27 samples, among them R5-tropic viruses were found in 13 (48.1%) patients and X4-variants - in 14 (51.9%) patients. The prevalence of drug resistance in naïve patients was low (1.5%) with the only one mutation K219Q found. The composition and distribution of HIV-1 genetic variants in Armenia is evidently influenced by the Russian and other FSU countries epidemic, due to the significant volume of Armenian migrant/re-emigrant flows. Continued surveillance of HIV-1 circulating subtypes and drug resistance in Armenia is important for the proper management of HIV infection in this country.
 
To fully define HLA-A11-restricted HIV-1-specific cytotoxic T-lymphocyte epitopes in China, a method combining the enzyme-linked immunospot (ELISPOT) assay with intracellular gamma interferon staining (ICS) of peripheral blood mononuclear cells (PBMC) was used to map the optimal epitopes targeted by ELISPOT and then to define the HLA restriction of epitopes by ICS. A novel HLA-A11-restricted CTL epitope and five other published HLA-A11-restricted epitopes previously identified by reverse immunogenetics or other methods were defined. The approach of integrating ELISPOT with ICS is both convenient and useful for the characterization of CTL responses to HIV-1 infection; this method is practical for defining novel epitopes and facilitates in developing new strategies for future vaccine design in China and other Asian countries.
 
Schematic representation of immunization DNA vectors. (A) The polycistronic DNA construct expressing HIV-1 structural genes (gag/pol and gp120) under control of one CMV promoter. The 1.6 kb HIV-1 gp120 clade B was fused in frame with 3.0 kb HIV-1 gag/pol amplicon. (B)The polycistronic DNA construct expressing HCV structural genes (core, E1 and E2). The core, E1, and truncated E2 gene amplicons (amino acids1-683) was amplified from the serum of a patient seropositive for HCV-1b and cloned into pVAX-1. 
HIV-1 and HCV-specific CD8+T cell response detected by intracellular cytokine staining (ICS) in the immunized groups. Splenocytes from immunized mice was stimulated with the cocktail of HIV-1 (env, gag and pol peptides) or HCV peptides (E1, E2 and core peptides) specific for HLA-A2.1, which described in material and methods. In addition, splenocytes were also stimulated with HIV-1 gag or HCV core peptides alone. The cells were surface and intracellularly stained and analyzed by flow cytometry. The results were analyzed with the WinMDI program. A: Dot plots show results from individual representative animals from each mouse group. Number 1: represents the cocktail of HIV-1 peptides. Number 2: represents the HIV-1 gag peptides. Number 3: represents the cocktail of HCV peptides. Number 4: represents HCV-core peptides. B: Splenocytes from each animal in the experimental groups were treated as described in figure 5A. Flow cytometry results for all animals from each group represent mean percentages ±S.E. (n=4) of IFN-+CD8 T cells. Statistically significant difference labeled with * indicates p 0.05. 
Dual infections with HIV-1 and Hepatitis C virus (HCV) may proceed in concert to cause severe disease. HIV positive individuals that become infected with HCV advance more rapidly to AIDS than those that are infected with HIV-1 alone. In this study, HLA-A2.1 mice were immunized with a combination vaccine including HIV and HCV immunogens (polycistronic DNA + proteins) or vaccine containing either HIV or HCV immunogens. Mice immunized with the combined HIV/HCV regimen had similar antibody titers as the group receiving either the HIV-1 or HCV only regimen. Proliferative immune responses showed that mice receiving the combined HIV/HCV vaccine exhibited a three fold higher stimulation index (SI) to gp120 than mice immunized with the vaccine containing HIV alone. To determine whether our vaccine strategy induced Th1 or Th2 immune responses, IFN-gamma and IL-4/IL-5 were measured. The combined HIV/HCV vaccine induced a higher level of Th1 responses to HIV-1 gag protein compared with the other groups, as measured by IFN-gamma production. Interestingly, detection of IFN-gamma by ELISPOT assay demonstrated that the combined HIV/HCV vaccine group had increased numbers of spot forming cells (SFC) to HIV-gp120 peptides when compared to that of the HIV-1 only vaccine group. The combined HIV/HCV vaccine group also showed an increase in SFC to HCV-core peptides in comparison with the group receiving the HCV only vaccine. Intracellular IFN-gamma staining confirmed the ELISPOT results and demonstrated that the combined HIV/HCV group had significantly higher percentages of HIV and HCV-specific CD8+ T cells in comparison to the groups receiving the HIV or HCV vaccines. These results suggest a new approach to maximize vaccine efficacy against HIV and HCV.
 
We investigated the virologic and immunologic responses to a mono-class, nucleoside/nucleotide reverse transcriptase inhibitor - combination therapy consisting of tenofovir and zidovudine/lamivudine/abacavir in therapy experienced patients. Retrospective study of 122 patients. Primary analysis was performed at 48 weeks. Virologic response was defined as viral load levels less than 400 copies/ml. About half of the patients had switched to tenofovir+ zidovudine/lamivudine/abacavir for simplification purposes or toxicity while the other half had experienced virologic failure. 80/122 (66%) responded. Median viral load decreased to 78 copies/ml at week 48; median CD4 count increased to 321 cells/mm(3). Of the 42 virologic failures, only 3 patients failed after week 24. 24/35 patients who had been on a non-suppressive zidovudine/lamivudine/abacavir-only regimen at baseline and added tenofovir to intensify, responded. 41/53 patients who switched from any nucleoside reverse transcriptase inhibitor-only regimen improved or maintained suppression. Genotypes were available for 85/122 patients. The only predictor of virologic failure was the combination 41L+210W+215Y/F mutational pattern. 16 of the patients who failed on tenofovir+ zidovudine/lamivudine/abacavir therapy selected new primary nucleoside reverse transcriptase inhibitor resistance mutations that they previously did not have. 48/85 (56%) patients with genotype tests had at least 3 (3-10; median 4) nucleoside reverse transcriptase inhibitor resistance-associated mutations in the past. Patients heavily pre-treated with nucleoside analogues may show response to mono-class tenofovir+ zidovudine/lamivudine/abacavir therapy despite having a history of failure with nucleoside reverse transcriptase inhibitors. Lower baseline viral load, higher baseline CD4 count were significant predictors for response. Archived 41L+210W+215Y/F mutational pattern was significantly associated with non-response.
 
A study was conducted in an HIV/AIDS Zimbabwean cohort to assess possible associations of pharmacogenetic variants with common adverse drug reactions (ADRs) during anti-retroviral treatment (ART) and/or tuberculosis (TB) treatment. Genotype and allele frequencies for CYP2B6 G516T, CYP2B6 T983C, CYP2A6*17, ABCB1 rs10276036 C>T, NAT2*5 and NAT2*14 were similar to those reported in literature for other African populations. The CYP2B6 516TT genotype and male gender were significantly associated with occurrence of Efavirenz induced central nervous system disorders (OR 20.58, p=0.004) and the ABCB1 rs10276036TT genotype with Nevirapine induced skin hypersensitivity (OR 4.01, p=0.04). For Stavudine, time on treatment was the main factor in development of lipodystrophy (OR 1.06, p<0.0001). For isoniazid, increasing patient age was associated with peripheral neuropathy (OR 1.05, p=0.001). Although genetic polymorphisms may play a role in predicting occurrence of ADRs, this study also indicates that other factors (gender, age, treatment time) are crucial in predicting drug-induced adverse effects.
 
Binding of HIV gp120 to the chemokine coreceptor CXCR4 mediates signal transduction that promotes actin dynamics critical for the establishment of viral latency in resting CD4 T cells. To some extent, this gp120-mediated signal transduction resembles the chemotactic response mediated by chemokines such as the stromal cell-derived factor-1 (SDF-1). It has been suggested that gp120 functions as a bona fide chemokine to attract or repel blood CD4 T cells. To determine whether gp120 is a viral chemoattractant, we compared the chemotactic properties of gp120 with those of SDF-1, and confirmed previous observations that gp120 possesses some chemotactic ability at certain dosages. However, when we examined gp120 in a range of dosages, we found that in general, gp120 only attracts or repels blood resting CD4 T cells at a low level, and there is no clear pattern of dosage-dependency as normally seen in a typical chemokine. These irregularities of gp120 were observed in multiple donors. Nevertheless, gp120 aberrantly interferes with SDF-1-mediated T cell chemotaxis and cell migration. These results suggest that gp120 does not act like a typical chemoattractant, although it triggers actin dynamics to facilitate HIV infection.
 
HIV-1 infection is associated with dysregulation of cytokine production by peripheral blood (PB) monocytes and dendritic cells (DC), but controversial results have been reported. We aimed to analyze the effect of antiretroviral therapy (ART) on the in vitro production of inflammatory cytokines by PB-stimulated monocytes and DC of myeloid origin -CD33(high+ ) myeloid DC (mDC) and CD33(+)/CD14(-/dim+)/CD16(high+) DC- from HIV-1+ patients and its relationship with CD4+ T-cell recovery and co-infection with hepatitis C virus (HCV). In vitro cytokine production was analyzed at the single cell level in 32 HIV-1+ patients, grouped according to the number of CD4+ T-cells/microl in PB (<200 CD4 versus >200 CD4). Patients were tested prior to therapy and at weeks +2, +4, +8, +12 and +52 after ART. Prior to ART, production of IL-6, TNF-alpha and IL-12 by mDC and of IL-8 and IL-12 by CD16+ DC was significantly increased among >200 CD4 patients. After one year of ART, increased production of IL-8 by monocytes, of TNF-alpha by mDC and of IL-1beta, IL-6 and TNF-alpha by CD16+ DC was specifically observed among <200 CD4 HIV-1+ individuals showing a high recovery of PB CD4+ T-cell counts. In turn, we found that the significantly reduced percentage of IL-1beta, IL-6, IL-8 and TNF-alpha-producing monocytes and of IL-6 and IL-8-producing mDC and CD16+ DC, as well as the significantly diminished mean amount of IL-6 produced per monocyte, mDC and CD16+ DC and of IL-12 produced per CD16+ DC observed at week +52 for the >200 CD4 patients, were related to the presence of co-infection with HCV. In summary, HIV-1+ individuals show abnormal production of inflammatory cytokines by PB-stimulated monocytes and DC of myeloid origin even after one year of ART, such abnormalities being associated with the degree of recovery of PB CD4+ T-cell counts in more immunocompromised patients and HCV co-infection in more immunocompetent HIV-1+ individuals.
 
Chromium is an essential micronutrient; chromium deficiency has been reported to cause insulin resistance, hyperglycemia and hyperlipidemia. The aim was to investigate the effect of chromium supplementation on insulin-resistance, other metabolic abnormalities, and body composition in people living with HIV. This was a randomized, double-blind, placebo-controlled trial. Fifty-two HIV-positive subjects with elevated glucose, lipids, or evidence of body fat redistribution, and who had insulin-resistance based on the calculation of homeostasis model of assessment (HOMA-IR > or = 2.5) were assessed. Subjects who were on insulin or hypoglycemic medications were excluded. Subjects were randomized to receive either 400 microg/day chromium-nicotinate or placebo for 16 weeks. Forty-six subjects, 23 in each group, completed the study. Fasting blood insulin, glucose, lipid profile and body composition were measured before and after intervention. Chromium was tolerated without side effects and resulted in a significant decrease in HOMA-IR (median (IQR) (pre:4.09 (3.02-8.79); post: 3.66 (2.40-5.46), p=0.004), insulin (pre: 102 (85-226); post: 99 (59-131) pmol/L, p=0.003), triglycerides, total body fat mass (mean+/-SEM) (pre: 17.3+/-1.7; post: 16.3+/-1.7 kg; p=0.002) and trunk fat mass (pre: 23.8+/-1.9; post: 22.7+/-2.0 %; p=0.008). Blood glucose, C-peptide, total, HDL and LDL cholesterol, and hemoglobin A1c remained unchanged. Biochemical parameters did not change in the placebo group except for LDL cholesterol which increased significantly. Body weight and medication profile remained stable throughout the study for both groups. In summary, chromium improved insulin resistance, metabolic abnormalities, and body composition in HIV+ patients. This suggests that chromium supplements alleviate some of the antiretroviral-associated metabolic abnormalities.
 
HIV-1 infection is associated with hematologic abnormalities including defective myelopoiesis. Most studies of myelopoiesis during HIV-1 infection were performed using unfractionated bone marrow-derived mononuclear cells, thus resulting in significant inter-individual variability in the numbers of cultured precursors. Here we evaluated the myelopoietic potential of circulating CD34+ progenitors by conducting a longitudinal analysis of antiretroviral therapy (ART)-induced changes of colony forming units-granulocyte and monocyte (CFU-GM) growth. Twelve HIV-infected individuals were studied longitudinally before and after initiation of ART (i.e. at a time when plasma HIV-RNA levels had become undetectable); thirty-one HIV-uninfected healthy individuals were enrolled as controls. Peripheral blood-derived CD34+ progenitors were purified by immunomagnetic sorting, and cultured in methylcellulose-based medium containing stem cell factor, granulocyte-monocyte colony-stimulating factor and interleukin-3. ART-induced changes in the proportion of CD8+ T cells expressing surface HLA-DR were also evaluated. We found that CFU-GM levels were increased in untreated HIV-infected individuals when compared to uninfected controls but declined significantly following ART, in parallel with the decline of HIV-RNA levels in plasma and with the down-regulation of HLA-DR expression on CD8+ T cells. These findings suggest that, in untreated HIV-infected individuals, chronic inflammation and/or immune activation is associated with defective myelopoiesis and accumulation of myeloid precursors. ART-induced suppression of HIV-1 replication is associated with normalization of CFU-GM levels.
 
Objective was to assess dietary intake and physical activity in a Canadian population sample of male patients with HIV and metabolic abnormalities and to compare the data to Canadian recommendations. Sixty-five HIV-infected men with at least one feature associated with the metabolic syndrome (insulin resistance, dyslipidemia, central obesity, or lipodystrophy) were enrolled. Results from 7-day food records and activity logs were compared to the Dietary Reference Intakes and recommendations of Canada's Physical Activity Guide, respectively. Anthropometric data were also measured. Fifty-two percent of the subjects were overweight, another 15% were obese. However, energy intake (mean+/-SEM) (2153+/-99 kcal/d) was lower than the estimated requirement (2854+/-62 kcal/d; p<0.0001), and 84.5% of the patients reached the recommended minimum of 60 min of mild or 30 min of moderate daily exercise. Intake was adequate for protein, but high for fat and cholesterol in 40% of patients. No patient reached the recommendation for fiber. Intake from diet alone was suboptimal for most micronutrients. Prevalence was highest for low vitamin E (91% of patients) and magnesium (68%) intake, and high sodium intake (72%). In summary, a large proportion of HIV patients with metabolic abnormalities were overweight or obese. However, this was not associated with high energy intake, or reduced physical activity. High fat, low fiber and inadequate micronutrient intakes were prevalent.
 
Cerebral white matter changes including tissue water diffusion abnormalities detected with diffusion tensor magnetic resonance imaging (DTI) are commonly found in humans with Human Immunodeficiency Virus (HIV) infection, as well as in animal models of the disorder. The severities of some of these abnormalities have been reported to correlate with measures of disease progression or severity, or with the degree of cognitive dysfunction. Accordingly, DTI may be a useful translational biomarker. HIV-Tat protein appears to be an important factor in the viral pathogenesis of HIV-associated neurotoxicity. We previously reported cerebral gray matter density reductions in the GT-tg bigenic mouse treated with doxycycline (Dox) to conditionally induce Tat protein expression. Presently, we administered intraperitoneal (i.p.) Dox (100 mg/kg/day) for 7 days to GT-tg mice to determine whether induction of conditional Tat expression led to the development of cerebral DTI abnormalities. Perfused and fixed brains from eight GT-tg mice administered Dox and eight control mice administered saline i.p. were extracted and underwent DTI scans on a 9.4 Tesla scanner. A whole brain analysis detected fractional anisotropy (FA) reductions in several areas including insular and endopiriform regions, as well as within the dorsal striatum. These findings suggest that exposure to Tat protein is sufficient to induce FA abnormalities, and further support the use of the GT-tg mouse to model some effects of HIV.
 
Unadjusted and Adjusted Cox Proportional Hazards Models Assessing Virological Failure After Achieving Initial Virological Suppression (N=328)
Comparing the Outcomes of Four Adjusted Cox Proportional Hazards Models Assessing the Impact of Aboriginal Ethnicity on Virological Failure After Achieving Initial Virological Suppression
To compare rates of initial virological suppression and subsequent virological failure by Aboriginal ethnicity after starting highly active antiretroviral therapy (HAART). We conducted a retrospective cohort study of antiretroviral-naïve HIV-patients starting HAART in January 1999-June 2005 (baseline), followed until December 31, 2005 in Alberta, Canada. We compared the odds of achieving initial virological suppression (viral load <500 copies/mL) by Aboriginal ethnicity using logistic regression and, among those achieving suppression, rates of virological failure (the first of two consecutive viral loads >1000 copies/mL) by Aboriginal ethnicity using cumulative incidence curves and Cox proportional hazards models. Sex, injection drug use as an HIV exposure category (IDU), baseline age, CD4 cell count, viral load, calendar year, and HAART regimen were considered as potential confounders. Of 461 study patients, 37% were Aboriginal and 48% were IDUs; 71% achieved initial virological suppression and were followed for 730.4 person-years. After adjusting for confounding variables, compared to non-Aboriginals with other exposures, the odds of achieving initial virological suppression were lower for Aboriginal IDUs (odds ratio (OR)=0.33, 95% CI=0.19-0.60, p=0.0002), non-Aboriginal IDUs (OR=0.30, 95% CI=0.15-0.60, p=0.0006), and Aboriginals with other exposures (OR=0.38, 95% CI=0.21-0.67, p=0.0009). Among those achieving suppression, Aboriginals experienced higher virological failure rates ≥1 year after suppression (hazard ratio=3.35, 95% CI=1.68-6.65, p=0.0006). Future research should investigate adherence among Aboriginals and IDUs treated with HAART and explore their treatment experiences to assess ways to improve outcomes.
 
Two HIV-1 non B subtype isolates, 98US_MSC5007 and 98US_MSC5016, which have been identified amongst the US Army personnel serving abroad, are known to have originated from other nations. Notwithstanding, they are categorized as American strains. This is because their countries of origin are unknown. American isolates are basically B subtype. 98US_MSC5007 belongs to Circulating Recombinant Form (CRF02_AG) while 98US_MSC5016 is of the C clade. Both sub-groups are recognized to have originated from African and Asian continents. It has become necessary to properly determine the countries of origin of microbes and viruses. This is because; diversity and cross-subtyping have been found to mitigate the designing and development of vaccine and therapeutic interventions. The aim of this study therefore is to identify the countries of origin of the two American isolates found amongst US Army personnel serving abroad. A Digital Signal Processing-based Bioinformatics technique called Informational Spectrum Method (ISM) is engaged. Spectral Position of Maximum Binding Interaction (SPMBI) is used. Several approaches including Phylogeny have preliminarily been employed in the determination of evolutionary trends of organisms and viruses. SPMBI has preliminarily been used to re-establish the semblance and common originality that exist between human and Chimpanzee, evolutionary roadmaps in the Influenza and HIV viruses. The results disclosed that 98US_MSC5007 shared same semblance and originality with a Nigeria isolate (92NG083) while 98US_MSC5016 with the Zairian isolates (EL, MAL, and Z2/CDC-34). These results appear to demonstrate that the American soldiers harboring these strains may have been infected by isolates from Nigeria and Zaire, respectively. This is because 98US_MSC5007 and the Nigerian isolate share SPMBI at position 44. Additionally, 98US_MSC5016, which has SPMBI at position 148, may have come from Zaire as it has similar SPMBI with the Zairian isolates at 150 and 149. SPMBI is a demonstration of Bio-functionality arising from maximum affinity by the proteins from different sources to a common protein. The findings are further repeated using ISM-based Phylogenetic technique. The outcome appears not to be in complete accord with the results derived obtained in this study. It is therefore recommended that the countries these US Army personnel are deployed be identified and where the findings made and the locations of the Army personnel appropriately correlate, this procedure be engaged in the identification of the nations of origins of all other HIV isolates across all clades and nations.
 
Top-cited authors
Paul R Gorry
  • Burnet Institute
Sylvie Bannwarth
  • Centre Hospitalier Universitaire de Nice
Suzanne M Crowe
  • Burnet Institute
Damian Purcell
  • University of Melbourne
Chi Ong