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Jared M Baeten,
Jairam Lingappa, Ingrid Beck,
Lisa M Frenkel,
Gregory Pepper,
Connie Celum,
Anna Wald,
Kenneth H Fife,
Edwin Were,
Nelly Mugo,
Jorge Sanchez,
Myron Essex,
Joseph Makhema,
James Kiarie,
Carey Farquhar,
Lawrence Corey
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ABSTRACT: Recent in vitro studies suggest that acyclovir may directly inhibit HIV-1 replication and can select for a specific HIV-1 reverse transcriptase mutation (V75I) with concomitant loss of an anti-HIV-1 effect. We tested for HIV-1 genotypic resistance at reverse transcriptase codon 75 in plasma from 168 HIV-1-infected persons from Botswana, Kenya, Peru, and the United States taking daily acyclovir or valacyclovir for between 8 weeks and 24 months. No V75I cases were detected (95% confidence interval, 0%-2.2%). These prospective in vivo studies suggest that standard-dose acyclovir or valacyclovir does not select for HIV-1 resistance.
The Journal of Infectious Diseases 01/2011; 203(1):117-21. · 6.41 Impact Factor
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ABSTRACT: A single dose of nevirapine (sdNVP) to prevent mother-to-child transmission of HIV-1 increases the risk of failure of subsequent NVP-containing antiretroviral therapy (ART), especially when initiated within 6 months of sdNVP administration, emphasizing the importance of understanding the decay of nevirapine-resistant mutants. Nevirapine-resistant HIV-1 genotypes (with the mutations K103N, Y181C, and/or G190A) from 21 women were evaluated 10 days and 6 weeks after sdNVP administration and at the initiation of ART. Resistance was assayed by consensus sequencing and by a more sensitive assay (oligonucleotide ligation assay [OLA]) using plasma-derived HIV-1 RNA and cell-associated HIV-1 DNA. OLA detected nevirapine resistance in more specimens than consensus sequencing did (63% versus 33%, P<0.01). When resistance was detected only by OLA (n=45), the median mutant concentration was 18%, compared to 61% when detected by both sequencing and OLA (n=51) (P<0.0001). The proportion of women whose nevirapine resistance was detected by OLA 10 days after sdNVP administration was higher when we tested their HIV-1 RNA (95%) than when we tested their HIV-1 DNA (88%), whereas at 6 weeks after sdNVP therapy, the proportion was greater with DNA (85%) than with RNA (67%) and remained higher with DNA (33%) than with RNA (11%) at the initiation of antiretroviral treatment (median, 45 weeks after sdNVP therapy). Fourteen women started NVP-ART more than 6 months after sdNVP therapy; resistance was detected by OLA in 14% of the women but only in their DNA. HIV-1 resistance to NVP following sdNVP therapy persists longer in cellular DNA than in plasma RNA, as determined by a sensitive assay using sufficient copies of virus, suggesting that DNA may be superior to RNA for detecting resistance at the initiation of ART.
Journal of clinical microbiology 02/2010; 48(5):1555-61. · 4.16 Impact Factor
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Ingrid A Beck,
Claudia Crowell,
Robin Kittoe,
Helba Bredell,
Molefe Machaba,
Carolyn Willamson,
Wouter Janssens,
Sabelle Jallow,
Guido van der Groen,
Yiming Shao,
Mini Jacob,
N M Samuel,
Ivette Lorenzana de Rivera,
Nicole Ngo-Giang-Huong,
Sharon Cassol,
George Alemnji,
Lisa M Frenkel
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ABSTRACT: We evaluated the feasibility of the oligonucleotide ligation assay (OLA), a specific, sensitive, and economical ligase-based point mutation assay designed to detect HIV-1 drug-resistance mutations at 12 codons of HIV-1 subtype B pol, for potential use in resource-poor settings.
Specimens from HIV-1-infected individuals collected by 7 international laboratories, including subtypes A, B, C, D, F, G, J, and recombinants AE and AG, were tested by the OLA developed for HIV-1 subtype B. Common polymorphisms that interfered with reactivity of the OLA were identified and modified probes designed and evaluated.
92.5% (2,410) of 2,604 codons in specimens from 217 individuals were successfully genotyped by the subtype B OLA. A high rate (range 8.3%-31.2%) of indeterminate results (negative OLA reaction for both mutant and wild type) was observed for 5 codons. Modified probes at reverse transcriptase codons 151 and 184 and protease codon 90 increased the rate of valid OLA to 96.1%.
The OLA designed for HIV-1 subtype B genotyped most pol codons in non-B subtypes from Asia and Africa but was improved by addition of several modified probes. International laboratories experienced in molecular techniques were able to perform the OLA.
JAIDS Journal of Acquired Immune Deficiency Syndromes 09/2008; 48(4):418-27. · 4.43 Impact Factor
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Caroline Mitchell,
Cheryl Jennings,
Donald Brambilla,
Grace Aldrovandi,
Angela Martin Amedee, Ingrid Beck,
James W Bremer,
Robert Coombs,
Don Decker,
Susan Fiscus,
Joseph Fitzgibbon,
Katherine Luzuriaga,
John Moye,
Paul Palumbo,
Patricia Reichelderfer,
Mohan Somasundaran,
Wendy Stevens,
Lisa Frenkel
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ABSTRACT: Collecting whole blood on filter paper simplifies the processing, transport, and storage of specimens used for the diagnosis of human immunodeficiency virus type 1 (HIV-1) and other tests. Specimens may be collected in tropical or rural areas with minimal facilities for handling specimens. To compare simulated tropical conditions with freezer storage, we examined the stability of HIV-1 DNA in dried blood spots (DBS) stored in humid heat and at -20 degrees C. DBS were created by spotting 50-microl aliquots of whole blood on 903 filter paper. DNA was extracted from DBS at baseline and after 2, 6, or 12 months of storage at -20 degrees C or at 37 degrees C with approximately 85% humidity. The DNA was tested undiluted or diluted using the Amplicor HIV-1 DNA PCR (Roche), version 1.5. Each reaction was scored positive, negative, or indeterminate based on optical density. Results were compared between storage conditions and over time. A total of 1,832 reactions from 916 DBS were analyzed, including 100 DBS at baseline, 418 stored at -20 degrees C, and 398 stored at 37 degrees C. A chi-square test showed fewer positive reactions for DBS stored at 37 degrees C (55%) than for those stored at -20 degrees C (78%) (P < 0.0001). Samples stored at -20 degrees C showed little change in the probability of detection of HIV-1 DNA over time; the odds ratio (OR) was 0.93 after storage for 1 year. Samples stored at 37 degrees C demonstrated a significant change in detection at 1 year (OR, 0.29). We conclude that exposure of DBS to 37 degrees C and high humidity impaired the recovery of HIV-1 DNA from DBS, whereas DNA recovery was preserved when DBS were stored frozen.
Journal of clinical microbiology 07/2008; 46(9):2945-9. · 4.16 Impact Factor
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Mark Dybul,
Elizabeth Nies-Kraske,
Robin Dewar,
Frank Maldarelli,
Claire W Hallahan,
Marybeth Daucher,
Stephen C Piscitelli,
Linda Ehler,
Ann Weigand,
Sarah Palmer,
Julia A Metcalf,
Richard T Davey,
Diane M Rock Kress,
April Powers, Ingrid Beck,
Lisa Frenkel,
Michael Baseler,
John Coffin,
Anthony S Fauci
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ABSTRACT: We previously demonstrated that short-cycle structured intermittent therapy (SIT; 7 days without therapy followed by 7 days with antiretroviral therapy [ART]) with a ritonavir-boosted, indinavir-based, twice-daily regimen maintained suppression of plasma HIV viremia while reducing serum levels of lipids. Adherence to such a regimen may be problematic for certain patients.
Eight patients with a history of receiving combination ART that maintained suppression of plasma HIV RNA to <50 copies/mL received a once-daily SIT regimen of didanosine, lamivudine, and efavirenz.
For 7 patients, suppression of plasma HIV RNA to <50 copies/mL was maintained for 60-84 weeks. Four patients with adequate samples had no evidence for an increase in plasma viremia for up to 72 weeks, by use of an assay with a limit of detection of <1 copy/mL. The lack of rebound viremia may be the result of the persistence of efavirenz in plasma on day 7 of the no-therapy period, as was detected in 7 of 7 patients. There was no significant change in CD4(+) T cell counts or serum hepatic transaminase or lipid levels.
A once-daily short-cycle SIT regimen maintained suppression of plasma HIV RNA while preserving CD4(+) T cell counts. Such a regimen may have importance in resource-limited settings where the monetary cost of continuous ART is prohibitive.
The Journal of Infectious Diseases 07/2004; 189(11):1974-82. · 6.41 Impact Factor
