P A Luciw

University of California, Davis, Davis, California, United States

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Publications (176)1035.43 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Combat wound healing and resolution are highly affected by the resident microbial flora. We therefore sought to achieve comprehensive detection of microbial populations in wounds using novel genomic technologies and bioinformatics analyses. We employed a microarray capable of detecting all sequenced pathogens for interrogation of 124 wound samples from extremity injuries in combat-injured U.S. service members. A subset of samples was also processed via next-generation sequencing and metagenomic analysis. Array analysis detected microbial targets in 51% of all wound samples, with Acinetobacter baumannii being the most frequently detected species. Multiple Pseudomonas species were also detected in tissue biopsies. Detection of Acinetobacter plasmid pRAY correlated significantly with wound failure, while detection of enteric-associated bacteria associated significantly with successful healing. Whole genome sequencing revealed broad microbial biodiversity between samples. Total wound bioburden did not associate significantly with wound outcome, although temporal shifts were observed over the course of treatment. Given that standard microbiological methods do not detect the full range of microbes in each wound, these data emphasize the importance of supplementation with molecular techniques for thorough characterization of wound-associated microbes. Future application of genomic protocols for assessing microbial content could allow for application of specialized care through early and rapid identification and management of critical patterns in wound bioburden.
    Journal of clinical microbiology 05/2014; · 4.16 Impact Factor
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    ABSTRACT: Using an established non-human primate model, rhesus macaques were infected intravenously with a chimeric simian immunodeficiency virus consisting of SIVmac239 with the HIV-1 reverse transcriptase from clone HXBc2 (RT-SHIV). The impact of two enhanced (four and five drug) highly active antiretroviral therapies (HAART) on early viral decay and rebound were determined. The four-drug combination included an integrase inhibitor, L-870-812 (L-812), together with a three drug regimen including emtricitabine [(-)-FTC], tenofovir [TFV], and efavirenz [EFV]. The five-drug combination consisted of one analog for each of the four the DNA precursors (using TFV, (-)-FTC, (-)-β-D-(2R,4R)-1,3-dioxolane-2,6-diaminopurine [Amdoxovir®, DAPD], and zidovudine [AZT] together with EFV. A cohort treated with a three drug combination of (-)-FTC, TFV and EFV served as treated controls. Daily administration of three, four or five drug combination of antiretroviral agents was initiated (at week 6 or 8 after inoculation), continued up to week 50, and then followed by a rebound period. Plasma samples were collected routinely and drug levels monitored using LC-MS/MS. Viral loads were monitored with a standard TaqMan qRT-PCR assay. Comprehensive analyses of replication dynamics were performed. RT-SHIV infection in rhesus macaques produced typical viral infection kinetics with untreated controls establishing persistent viral loads of > 10(4) copies of RNA/mL. RT-SHIV viral loads at start of treatment (V0) were similar in all treated cohorts (p > 0.5). All antiretroviral drug levels were measureable in plasma. The four-drug and five-drug combination regimens (enhanced HAART) improved suppression of viral load (within one wk, p < 0.01) and had an overall greater potency (p < 0.02) than the three-drug regimen (HAART). Moreover, rebound viremia occurred rapidly following cessation of any treatment. The enhanced HAART (four- or five-drug combinations) had significant improvement in viral suppression compared to the three-drug combination, but no combination was sufficient to eliminate viral reservoirs.
    Antimicrobial Agents and Chemotherapy 04/2014; · 4.57 Impact Factor
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    ABSTRACT: Blast wounds often involve diverse tissue types and require substantial time and treatment for appropriate healing. Some of these subsequent wounds become colonized with bacteria requiring a better understanding of how the host responds to these bacteria and what proteomic factors contribute wound healing outcome. In addition, using reliable and effective proteomic sample preparation procedures can lead to novel biomarkers for improved diagnosis and therapy. To address this need, suitable sample preparation for 2-D DIGE proteomic characterization of wound effluent and serum samples from combat-wounded patients was investigated. Initial evaluation of crude effluent and serum proved the necessity of high abundant protein depletion. Subsequently, both samples were successfully depleted using Agilent Multiple Affinity Removal system and showed greatly improved 2-D spot maps, comprising 1,800 and 1,200 protein spots, respectively. High abundant protein removal was necessary for both wound effluent and serum. This is the first study to show a successful method for high abundant protein depletion from wound effluent which is compatible with downstream 2-D DIGE analysis. This development allows for improved biomarker discovery in wound effluent and serum samples.
    Proteome Science 02/2014; 12(1):10. · 2.42 Impact Factor
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    ABSTRACT: Tuberculosis (TB) in non-human primates (NHPs) is highly contagious, requiring efficient identification of animals infected with Mycobacterium tuberculosis. Tuberculin skin test is usually used but lacks desirable sensitivity/specificity and efficiency. We aimed to develop an immunoassay for plasma antibodies against M. tuberculosis. A key challenge is that not all infected animals contain antibodies against the same M. tuberculosis antigen. Therefore, a multiplex panel of 28 antigens (Luminex(®) -Platform) was developed. Data revealed antibodies against eight antigens (Rv3875, Rv3875-Rv3874 fusion, Rv3874, Rv0934, Rv3881, Rv1886c, Rv2031, Rv3841) in experimentally infected (M. tuberculosis strains: Erdman and H37Rv) NHPs (rhesus and cynomolgus macaques). In a naturally acquired M. tuberculosis infection, rhesus macaques (n = 15) with lung TB pathology (n = 10) contained antibodies to five additional antigens (Rv0831, Rv2220, Rv0054, Rv1099, and Rv0129c). Results suggest that this user-friendly and easily implementable multiplex panel, containing 13 M. tuberculosis antigens, may provide a high-throughput alternative for NHP TB screening.
    Journal of Medical Primatology 01/2014; · 1.11 Impact Factor
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    ABSTRACT: Highly active antiretroviral therapy (HAART) can reduce levels of human immunodeficiency virus type 1 (HIV-1) to undetectable levels in infected individuals, but the virus is not eradicated. The mechanisms of viral persistence during HAART are poorly defined, but some reservoirs have been identified, such as latently infected resting memory CD4(+) T cells. During latency, in addition to blocks at the initiation and elongation steps of viral transcription, there is a block in the export of viral RNA (vRNA), leading to the accumulation of multiply-spliced transcripts in the nucleus. Two of the genes encoded by the multiply-spliced transcripts are Tat and Rev, which are essential early in the viral replication cycle and might indicate the state of infection in a given population of cells. Here, the levels of multiply-spliced transcripts were compared to the levels of gag-containing RNA in tissue samples from RT-SHIV-infected rhesus macaques treated with HAART. Splice site sequence variation was identified during development of a TaqMan PCR assay. Multiply-spliced transcripts were detected in gastrointestinal and lymphatic tissues, but not the thymus. Levels of multiply-spliced transcripts were lower than levels of gag RNA, and both correlated with plasma virus loads. The ratio of multiply-spliced to gag RNA was greatest in the gastrointestinal samples from macaques with plasma virus loads <50 vRNA copies per mL at necropsy. Levels of gag RNA and multiply-spliced mRNA in tissues from RT-SHIV-infected macaques correlate with plasma virus load.
    PLoS ONE 01/2014; 9(2):e87914. · 3.53 Impact Factor
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    ABSTRACT: Multiplex microbead immunoassay (MMIA) is a powerful technology for a wide range of biomedical and clinical applications. It is important to study the normal concentration ranges of immunomodulators under different sample preparation conditions and age groups of subjects in order to more precisely determine their reference values for use in assessing alterations of their levels in disease. The aim of this study was to determine the plasma concentrations of immunomodulators (cytokines, chemokines and growth factors) in the peripheral blood from healthy subjects by the use of a large multiplex panel, and to determine the effects of different anticoagulants, age and gender on the immunomodulator levels. In addition, the assay precision for these biomarker analytes was determined. Plasma samples from 107 healthy subjects, aged 18-85 years, were collected in three different anticoagulants (sodium citrate, EDTA, Heparin); corresponding serum samples were also obtained. Multiplex microbead immunoassays were performed for measuring a total of 23 analytes including chemokines, cytokines and growth factors (IL-1β, IL-1ra, IL-2, IL-6, IL-7, IL-8, IL-12 p70, IL-17, IFN-γ, IP-10, MCP-1, PDGF-BB, RANTES, TNF-α, IL-1a, IL-16, HGF, MIG, TNF- β, PDGF-ABBB, EGF, Flt-3 Ligand, VEGF). For these analytes, our results showed that the anticoagulant affected the concentration measurements and the coefficients of variation. However, the relative levels of the analytes (profiles) of samples collected in a particular anticoagulant are consistent. The analytes IL-1 β, IL-7, Fit3-Ligand and IL-12p70 show the largest variation (up to four-fold) between the age groups. In addition, no statistically significant differences in the level of the analytes were found between the sexes. © 2013 Clinical Cytometry Society
    Cytometry Part B Clinical Cytometry 12/2013; · 2.23 Impact Factor
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    ABSTRACT: The ability to forecast whether a wound will heal after closure without further debridement(s), would provide substantial benefits to patients with severe extremity trauma. Wound effluent is a readily available material which can be collected without disturbing healthy tissue. For analysis of potential host response biomarkers, forty four serial combat wound effluent samples from 19 patients with either healing or failing traumatic- and other combat-related wounds were examined by 2-D DIGE. Spot map patterns were correlated to eventual wound outcome (healed or wound failure) and analyzed using DeCyder 7.0 and differential proteins identified via LC-MS/MS. This approach identified 52 protein spots that were differentially expressed and thus represent candidate biomarkers for this clinical application. Many of these proteins are intimately involved in inflammatory and immune responses. Furthermore, discriminate analysis further refined the 52 differential protein spots to a smaller subset of which successfully differentiate between wounds that will heal and those that will fail and require further surgical intervention with greater than 83% accuracy. These results suggest candidates for a panel of protein biomarkers that may aid traumatic wound care prognosis and treatment. We recommend that this strategy be refined, and then externally validated, in future studies of traumatic wounds.
    Journal of Translational Medicine 11/2013; 11(1):281. · 3.46 Impact Factor
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    ABSTRACT: Host immune responses to Mycobacterium tuberculosis (M. tb.) are generally able to contain infection and maintain a delicate balance between protection and immunopathology. A shift in this balance appears to underlie active disease observed in about ten percent of infected individuals. Effects of local inflammation, combined with anti-M. tb. systemic immune responses, are directly detectable in peripheral circulation, without ex vivo stimulation of blood cells or biopsy of the affected organs. We studied plasma immunomodulator and antibody biomarkers in patients with active pulmonary TB by a combination of multiplex microbead immunoassays and computational tools for data analysis. Plasma profiles of ten immunomodulators and antibodies against eight M. tb. antigens (previously reported by us) were examined in active pulmonary TB patients in a TB endemic country, Pakistan. Multiplex analyses were performed on samples from apparently healthy individuals, without active TB, from the same community as the TB patients to establish the assay baselines for all analytes. Over three thousand data points were collected from patients (n=135) and controls (n=37). The data were analyzed by multivariate and computer assisted cluster analyses to reveal patterns of plasma immunomodulators and antibodies. This study shows plasma profiles that in most patients represented either strong antibody or strong immunomodulator biomarkers. Profiling of a combination of both immunomodulators and antibodies described here may be valuable for the analysis of host immune responses in active TB in endemic countries.
    Clinical and vaccine Immunology: CVI 06/2013; · 2.60 Impact Factor
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    ABSTRACT: FIV establishes a latent infection in peripheral CD4+ T-cells, and the latent FIV promoter is associated with deacetylated, methylated histones, consistent with a restrictive chromatin structure. Here we explored the use of 5 histone-modifying agents - 4 histone deacetylase inhibitors (HDACi) and 1 histone methyltransferase inhibitor (HMTi) - to reactivate latent FIV ex vivo. All compounds tested were able to alter histone lysine residue modifications in feline cells, both globally and at the FIV promoter locally. When latently FIV-infected peripheral CD4+ T-cells were cultured ex vivo in the presence of these inhibitors, viral transcription was significantly activated relative to no treatment controls. Transcriptional reactivation of virus mediated by the HDACi suberoylanilide hydroxamic acid (SAHA) was dose-dependent, detected after as little as 1h of exposure, and resulted in virion formation as evidenced by supernatant reverse transcriptase activity. A synergistic effect was not found when SAHA was combined with HMTi under the conditions tested. At low therapeutically relevant concentrations in primary feline PBMC, SAHA was found to be minimally cytotoxic and non-immune activating. HDACi and HMTi can reactivate latent FIV ex vivo, and SAHA, also known as the anticancer drug Vorinostat, in particular is a promising candidate for in vivo use because of its efficacy, potency, and relative safety. Use of the FIV/cat model of lentiviral latency to explore in vivo treatment with SAHA and other anti-latency therapeutics will allow investigations that are either ethically or logistically not addressable in patients persistently infected with human immunodeficiency virus (HIV-1).
    Virus Research 10/2012; · 2.75 Impact Factor
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    Retrovirology 09/2012; 9(2). · 5.66 Impact Factor
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    ABSTRACT: Early secreted antigenic target protein 6 (esat6) is one of the genes present on region of difference 1 (RD1) of Mycobacterium tuberculosis (M. tb) genome. This RD1 is a characteristic of virulent strains of M. tb and Mycobacterium bovis and this is one of the major differences between the disease causing strains and Bacillus-Calmat Guerin (BCG) vaccine strains. Studies have proved the presence of large number of memory T cells in M. tb infected individuals and these memory cells are reactive towards Esat6 antigen, which highlighted the importance of this gene especially in early infections. In this study, numbers of esat6 gene constructs were made in order to get a suitable construct to be used as good DNA vaccine. First esat6 gene construct was made in pND vector without Kozak sequence upstream the gene, second construct was made in pcDNA3.1 vector with Kozak sequence upstream the gene, third construct was made again in pND vector with Kozak sequence, fourth construct was made with Kozak sequence upstream and GGG downstream the ATG as a second codon of gene first in pcDNA3.1 and later in pND vectors respectively which was designated as construct five. Sixth construct was a fusion and in pcDNA3.1 vector with Kozak upstream the gene and epitope V and poly histidine tail sequence provided by vector down stream the gene through in-frame cloning of esat6 gene with sequences provided by vector by removing stop codon through PCR based primers. Seventh and final construct was prepared in pND14 vector also as a fusion construct and gene was cloned under tissue plasminogen activator sequence in an in-frame through PCR based primers. All these constructs were subjected to 293T human embryonic kidney cell lines to evaluate their level of expression. Although none of the constructs gave detectable level of expression in cultured cells when tested through Western blots (WB) but tpa-esat6-pND14 construct was selected as potential DNA vaccine candidate to inject intramuscularly and interadermally to balb/c mice along with controls to obtain detectable response in vivo. Animals were tested nine weeks post vaccination and found positive against tpa-esat6-pND14 vaccine through WB and multiplex micro bead immunoassay (MMIA).
    07/2012; 45:749-757.
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    ABSTRACT: Infection with HIV-1 results in marked immunologic insults and structural damage to the intestinal mucosa, including compromised barrier function. While the development of highly active antiretroviral therapy (HAART) has been a major advancement in the treatment of HIV-1 infection, the need for novel complementary interventions to help restore intestinal structural and functional integrity remains unmet. Known properties of pre-, pro-, and synbiotics suggest that they may be useful tools in achieving this goal. This was a 4-week parallel, placebo-controlled, randomized pilot trial in HIV-infected women on antiretroviral therapy. A synbiotic formulation (Synbiotic 2000®) containing 4 strains of probiotic bacteria (10(10) each) plus 4 nondigestible, fermentable dietary fibers (2.5 g each) was provided each day, versus a fiber-only placebo formulation. The primary outcome was bacterial translocation. Secondary outcomes included the levels of supplemented bacteria in stool, the activation phenotype of peripheral T-cells and monocytes, and plasma levels of C-reactive protein and soluble CD14. Microbial translocation, as measured by plasma bacterial 16S ribosomal DNA concentration, was not altered by synbiotic treatment. In contrast, the synbiotic formulation resulted in significantly elevated levels of supplemented probiotic bacterial strains in stool, including L. plantarum and P. pentosaceus, with the colonization of these two species being positively correlated with each other. T-cell activation phenotype of peripheral blood lymphocytes showed modest changes in response to synbiotic exposure, with HLA-DR expression slightly elevated on a minor population of CD4+ T-cells which lack expression of HLA-DR or PD-1. In addition, CD38 expression on CD8+ T-cells was slightly lower in the fiber-only group. Plasma levels of soluble CD14 and C-reactive protein were unaffected by synbiotic treatment in this study. Synbiotic treatment for 4 weeks can successfully augment the levels of probiotic species in the gut during chronic HIV-1 infection. Associated changes in microbial translocation appear to be absent, and markers of systemic immune activation appear largely unchanged. These findings may help inform future studies aimed at testing pre- and probiotic approaches to improve gut function and mucosal immunity in chronic HIV-1 infection. Clinical Trials.gov: NCT00688311.
    BMC Complementary and Alternative Medicine 06/2012; 12:84. · 2.08 Impact Factor
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    ABSTRACT: Many resource-poor countries are faced with concurrent epidemics of AIDS and tuberculosis (TB) caused by human immunodeficiency virus (HIV) and Mycobacterium tuberculosis, respectively. Dual infections with HIV and M. tuberculosis are especially severe in infants. There is, however, no effective HIV vaccine, and the only licensed TB vaccine, the Mycobacterium bovis bacillus Calmette-Guérin (BCG) vaccine, can cause disseminated mycobacterial disease in HIV-infected children. Thus, a pediatric vaccine to prevent HIV and M. tuberculosis infections is urgently needed. We hypothesized that a highly attenuated M. tuberculosis strain containing HIV antigens could be safely administered at birth and induce mucosal and systemic immune responses to protect against HIV and TB infections, and we rationalized that vaccine safety could be most rigorously assessed in immunocompromised hosts. Of three vaccine candidates tested, the recombinant attenuated M. tuberculosis strain mc(2)6435 carrying a simian immunodeficiency virus (SIV) Gag expression plasmid and harboring attenuations of genes critical for replication (panCD and leuCD) and immune evasion (secA2), was found to be safe for oral or intradermal administration to non-SIV-infected and SIV-infected infant macaques. Safety was defined as the absence of clinical symptoms, a lack of histopathological changes indicative of M. tuberculosis infection, and a lack of mycobacterial dissemination. These data represent an important step in the development of novel TB vaccines and suggest that a combination recombinant attenuated M. tuberculosis-HIV vaccine could be a safe alternative to BCG for the pediatric population as a whole and, more importantly, for the extreme at-risk group of HIV-infected infants.
    Clinical and vaccine Immunology: CVI 06/2012; 19(8):1170-81. · 2.60 Impact Factor
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    ABSTRACT: Rapid detection and therapeutic intervention for infectious and emerging diseases is a major scientific goal in biodefense and public health. Toward this end, cytokine profiles in human blood were investigated using a human whole blood ex vivo exposure model, called WEEM. Samples of whole blood from healthy volunteers were incubated with seven pathogens including Yersinia pseudotuberculosis, Yersinia enterocolitica, Bacillus anthracis, and multiple strains of Yersinia pestis, and multiplexed protein expression profiling was conducted on supernatants of these cultures with an antibody array to detect 30 cytokines simultaneously. Levels of 8 cytokines, IL-1α, IL-1β, IL-6, IL-8, IL-10, IP-10, MCP-1 and TNFα, were significantly up-regulated in plasma after bacterial exposures of 4 hours. Statistical clustering was applied to group the pathogens based on the host response protein expression profiles. The nearest phylogenetic neighbors clustered more closely than the more distant pathogens, and all seven pathogens were clearly differentiated from the unexposed control. In addition, the Y. pestis and Yersinia near neighbors were differentiated from the B. anthracis strains. Cluster analysis, based on host response cytokine profiles, indicates that distinct patterns of immunomodulatory proteins are induced by the different pathogen exposures and these patterns may enable further development into biomarkers for diagnosing pathogen exposure.
    BMC Microbiology 05/2012; 12:79. · 2.98 Impact Factor
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    ABSTRACT: Feline immunodeficiency virus (FIV), the lentivirus of domestic cats responsible for feline AIDS, establishes a latent infection in peripheral blood CD4+ T-cells approximately eight months after experimental inoculation. In this study, cats experimentally infected with the FIV-C strain in the asymptomatic phase demonstrated an estimated viral load of 1 infected cell per approximately 10(3) CD4+ T-cells, with about 1 copy of viral DNA per cell. Approximately 1 in 10 proviral copies was capable of transcription in the asymptomatic phase. The latent FIV proviral promoter was associated with deacetylated, methylated histones, which is consistent with a condensed chromatin structure. In contrast, the transcriptionally active FIV promoter was associated with histone acetylation and demethylation. In addition, RNA polymerase II appeared to be paused on the latent viral promoter, and short promoter-proximal transcripts were detected. Our findings for the FIV promoter in infected cats are similar to results obtained in studies of human immunodeficiency virus (HIV)-1 latent proviruses in cell culture in vitro studies. Thus, the FIV/cat model may offer insights into in vivo mechanisms of HIV latency and provides a unique opportunity to test novel therapeutic interventions aimed at eradicating latent virus.
    Viruses 05/2012; 4(5):878-88. · 2.51 Impact Factor
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    ABSTRACT: Feline immunodeficiency virus (FIV) is a lentivirus of cats that establishes a lifelong persistent infection with immunologic impairment. In an approximately 2 year-long experimental infection study, cats infected with a biological isolate of FIV clade C demonstrated undetectable plasma viral loads from 10 months post-infection onward. Viral DNA was detected in CD4+CD25+ and CD4+CD25- T cells isolated from infected cats whereas viral RNA was not detected at multiple time points during the early chronic phase of infection. Viral transcription could be reactivated in latently infected CD4+ T cells ex vivo as demonstrated by detectable FIV gag RNA and 2-long terminal repeat (LTR) circle junctions. Viral LTR and gag sequences amplified from peripheral blood mononuclear cells during early and chronic stages of infection demonstrated minimal to no viral sequence variation. Collectively, these findings are consistent with FIV latency in peripheral blood CD4+ T cells isolated from chronically infected cats. The ability to isolate latently FIV-infected CD4+ T lymphocytes from FIV-infected cats provides a platform for the study of in vivo mechanisms of lentiviral latency.
    Retrovirology 01/2012; 9:12. · 5.66 Impact Factor
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    ABSTRACT: The Kaposi sarcoma-associated herpesvirus (KSHV) latency-associated nuclear antigen (LANA) is a multifunctional protein with roles in gene regulation and maintenance of viral latency. Post-translational modification of LANA is important for functional diversification. Here, we report that LANA is subject to arginine methylation by protein arginine methyltransferase 1 in vitro and in vivo. The major arginine methylation site in LANA was mapped to arginine 20. This site was mutated to either phenylalanine (bulky hydrophobic, constitutive methylated mimetic) or lysine (positively charged, non-arginine methylatable) residues. The significance of the methylation in LANA function was examined in both the isolated form and in the context of the viral genome through the generation of recombinant KSHV. In addition, authentic LANA binding sites on the KSHV episome in naturally infected cells were identified using a whole genome KSHV tiling array. Although mutation of the methylation site resulted in no significant difference in KSHV LANA subcellular localization, we found that the methylation mimetic mutation resulted in augmented histone binding in vitro and increased LANA occupancy at identified LANA target promoters in vivo. Moreover, a cell line carrying the methylation mimetic mutant KSHV showed reduced viral gene expression relative to controls both in latency and in the course of reactivation. These results suggest that residue 20 is important for modulation of a subset of LANA functions and properties of this residue, including the hydrophobic character induced by arginine methylation, may contribute to the observed effects.
    Journal of Biological Chemistry 12/2011; 287(8):5806-18. · 4.65 Impact Factor
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    ABSTRACT: Two billion people are infected with Mycobacterium tuberculosis, the etiological agent of tuberculosis (TB), worldwide. Ten million to 20 million of the infected individuals develop disease per year. TB is a treatable disease, provided that it is diagnosed in a timely manner. The current TB diagnostic methods are subjective, inefficient, or not cost-effective. Antibody-based blood tests can be used efficiently and cost-effectively for TB diagnosis. A major challenge is that different TB patients generate antibodies against different antigens. Therefore, a multiplex immunoassay approach is needed. We have developed a multiplex panel of 28 M. tuberculosis antigen-coated microbeads. Plasma samples were obtained from over 300 pulmonary TB patients and healthy controls in a country where TB is endemic, Pakistan. Multiplex data were analyzed using computational tools by multivariate statistics, classification algorithms, and cluster analysis. The results of antibody profile-based detection, using 16 selected antigens, closely correlated with those of the sputum-based diagnostic methods (smear microscopy and culture) practiced in countries where TB is endemic. Multiplex microbead immunoassay had a sensitivity and specificity of approximately 90% and 80%, respectively. These antibody profiles could potentially be useful for the diagnosis of nonpulmonary TB, which accounts for approximately 20% of cases of disease. Since an automated, high-throughput version of this multiplex microbead immunoassay could analyze thousands of samples per day, it may be useful for the diagnosis of TB in millions of patients worldwide.
    Clinical and vaccine Immunology: CVI 12/2011; 18(12):2148-53. · 2.60 Impact Factor
  • V. V. Krishhan, Imran H. Khan, Paul A. Luciw
    Molecular Analysis and Genome Discovery, Second Edition, 10/2011: pages 244 - 270; , ISBN: 9781119977438
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    ABSTRACT: Infection with Mycobacterium tuberculosis primarily produces a multifocal distribution of pulmonary granulomas in which the pathogen resides. Accordingly, quantitative assessment of the bacterial load and pathology is a substantial challenge in tuberculosis. Such assessments are critical for studies of the pathogenesis and for the development of vaccines and drugs in animal models of experimental M. tuberculosis infection. Stereology enables unbiased quantitation of three-dimensional objects from two-dimensional sections and thus is suited to quantify histological lesions. We have developed a protocol for stereological analysis of the lung in rhesus macaques inoculated with a pathogenic clinical strain of M. tuberculosis (Erdman strain). These animals exhibit a pattern of infection and tuberculosis similar to that of naturally infected humans. Conditions were optimized for collecting lung samples in a nonbiased, random manner. Bacterial load in these samples was assessed by a standard plating assay, and granulomas were graded and enumerated microscopically. Stereological analysis provided quantitative data that supported a significant correlation between bacterial load and lung granulomas. Thus this stereological approach enables a quantitative, statistically valid analysis of the impact of M. tuberculosis infection in the lung and will serve as an essential tool for objectively comparing the efficacy of drugs and vaccines.
    AJP Lung Cellular and Molecular Physiology 08/2011; 301(5):L731-8. · 3.52 Impact Factor

Publication Stats

8k Citations
1,035.43 Total Impact Points


  • 1987–2014
    • University of California, Davis
      • • Center for Comparative Medicine
      • • Department of Pathology and Laboratory Medicine
      • • Department of Pathology, Microbiology and Immunology (VM)
      • • Department of Veterinary Medicine and Epidemiology
      • • Cancer Center
      • • School of Medicine
      Davis, California, United States
  • 2011
    • University of Hertfordshire
      Hatfield, England, United Kingdom
  • 2003–2010
    • CSU Mentor
      Long Beach, California, United States
  • 2009
    • California State University, Fresno
      • Department of Chemistry
      Fresno, CA, United States
  • 2008
    • Wisconsin National Primate Research Center
      Madison, Wisconsin, United States
    • Novartis Vaccines
      Cambridge, Massachusetts, United States
  • 2002
    • Claude Bernard University Lyon 1
      Villeurbanne, Rhône-Alpes, France
    • Duke University Medical Center
      • Department of Surgery
      Durham, North Carolina, United States
  • 1983–2002
    • University of California, San Francisco
      • • Gladstone Institute
      • • Division of Hospital Medicine
      • • Department of Microbiology and Immunology
      San Francisco, CA, United States
  • 1998
    • The Rockefeller University
      New York City, New York, United States
  • 1989
    • Emory University
      Atlanta, Georgia, United States
  • 1987–1989
    • Howard Hughes Medical Institute
      Ashburn, Virginia, United States
  • 1988
    • National Cancer Institute (USA)
      • Laboratory of Molecular Biology
      Maryland, United States