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1.  Transmitted Antiretroviral Drug Resistance and Thumb Subdomain Polymorphisms Among Newly HIV Type 1 Diagnosed Patients Infected with CRF01_AE and CRF07_BC Virus in Guangdong Province, China 
AIDS Research and Human Retroviruses  2012;28(12):1723-1728.
The aim of this study was to elucidate the prevalence of transmitted drug-resistant (TDR) mutations and reverse transcriptase (RT) thumb subdomain polymorphisms in CRF01_AE and CRF07_BC virus among newly diagnosed, therapy-naive HIV-1 patients in Guangdong Province, China. One hundred and sixty-four samples were collected in the Guangzhou Eighth People's Hospital. The entire protease gene and 300 codons of the entry part of the reverse transcriptase were amplified and sequenced. Furthermore, genotypic drug resistance, polymorphisms, and their phylogeny were analyzed. According to eligibility criteria, seven samples were excluded, and 119 of 157 (75.8%) samples (84 CRF01_AE and 35 CRF07_BC) were amplified and sequenced successfully. The prevalence of TDR identified in the present study was 6.7% [8/119, 95% confidence interval (CI) 1.8–11.6%]. Three major resistance mutations, K103N, M184V, and Y188L, each of which caused more than one drug resistance, appeared in only two patients; the prevalence [1.7 % (2/119)] was relatively low. Until now, this is the first observation of the five newly identified accessory mutations, V35T, K43E, V60I, K122E, and E203D, and seven thumb subdomain polymorphisms, A272P, K277R, K281R, T286A, E291D, V292I, and I293V, in the RT gene in China. These findings provide useful information for guidance on the antiretroviral therapy (ART) policy in China where therapeutic options are still limited.
PMCID: PMC3505042  PMID: 22587343
2.  Prevalence of Anemia and Underlying Iron Status in Naive Antiretroviral Therapy HIV-Infected Children with Moderate Immune Suppression 
AIDS Research and Human Retroviruses  2012;28(12):1679-1686.
Anemia is common in HIV-infected children and iron deficiency is thought to be a common cause. This study investigates the prevalence of anemia, thalassemia, and underlying iron status in Thai and Cambodian children without advanced HIV disease to determine the necessity of routine iron supplementation. Antiretroviral (ARV)-naive HIV-infected Asian children aged 1–12 years, with CD4 15–24%, CDC A or B, and hemoglobin (Hb) ≥7.5 g/dl were eligible for the study. Iron studies, serum ferritin, Hb typing, and C-reactive protein were assessed. Anemia was defined as Hb <11.0 g/dl in children <5 years of age or <11.5 g/dl in children 5–12 years. We enrolled 299 children; 57.9% were female and the mean (SD) age was 6.3 (2.9) years. The mean (SD) CD4% and HIV-RNA were 20% (4.6) and 4.6 (0.6) log10 copies/ml, respectively. The mean (SD) Hb and serum ferritin were 11.2 (1.1) g/dl and 78.3 (76.4) μg/liter, respectively. The overall iron deficiency anemia (IDA) prevalence was 2.7%. One hundred and forty-eight (50%) children had anemia, mostly of a mild degree. Of these, 69 (46.6%) had the thalassemia trait, 62 (41.8%) had anemia of chronic disease (ACD), 9 (6.1%) had thalassemia diseases, 3 (2.0%) had iron deficiency anemia, and 5 (3.4%) had IDA and the thalassemia trait. The thalassemia trait was not associated with increased serum ferritin levels. Mild anemia is common in ARV-naïve Thai and Cambodian children without advanced HIV. However, IDA prevalence is low; with the majority of cases caused by ACD. A routine prescription of iron supplement in anemic HIV-infected children without laboratory confirmation of IDA should be discouraged, especially in regions with a high prevalence of thalassemia and low prevalence of IDA.
PMCID: PMC3505043  PMID: 22734817
3.  Risk Factors for Short-Term Virologic Outcomes Among HIV-Infected Patients Undergoing Regimen Switch of Combination Antiretroviral Therapy 
AIDS Research and Human Retroviruses  2012;28(12):1630-1636.
We investigated risk factors for unfavorable virologic responses among HIV-infected patients who recently switched antiretroviral regimens. We identified HIV-infected patients who switched antiretroviral regimens (defined as adding ≥2 new medications) between 2001 and 2008 at Kaiser Permanente California. Virological response, measured after 6 months on the new regimen, was classified as (1) maximal viral suppression (HIV RNA <75/ml), (2) low-level viremia (LLV; 75–5000/ml), or (3) advanced virologic failure (>5000/ml). Potential risk factors examined included (1) HIV disease factors, e.g., prior AIDS, CD4 cell count; (2) history of antiretroviral use, e.g., therapy classes of the newly switched regimen, medication adherence, and virologic failure at previous regimens; and (3) novel patient-level factors including comorbidities and healthcare utilization. Adjusted odds ratios (aOR) for LLV and advanced virologic failure were obtained from multivariable nominal logistic regression models. A total of 3447 patients were included; 2608 (76%) achieved maximal viral suppression, 420 (12%) had LLV, and 419 (12%) developed advanced virologic failure. Factors positively associated with LLV and advanced virologic failure included number of regimens prior to switch [aORper regimen=1.38 (1.17–1.62) and 1.77 (1.50–2.08), respectively], nucleotide reverse transcriptase inhibitor-only regimens (vs. protease inhibitor-based) [aOR=2.78 (1.28–6.04) and 5.10 (2.38–10.90), respectively], and virologic failure at previous regimens [aOR=3.15 (2.17–4.57) and 4.71 (2.84–7.81), respectively]. Older age, higher CD4 cell count, and medication adherence were protective for unfavorable virologic outcomes. Antiretroviral regimen-level factors and immunodeficiency were significantly associated with virologic failure after a recent therapy switch and should be considered when making treatment change decisions.
PMCID: PMC3505044  PMID: 22475276
4.  Antiretroviral Drug Susceptibility Among HIV-Infected Adults Failing Antiretroviral Therapy in Rakai, Uganda 
AIDS Research and Human Retroviruses  2012;28(12):1739-1744.
We analyzed antiretroviral drug susceptibility in HIV-infected adults failing first- and second-line antiretroviral treatment (ART) in Rakai, Uganda. Samples obtained from participants at baseline (pretreatment) and at the time of failure on first-line ART and second-line ART were analyzed using genotypic and phenotypic assays for antiretroviral drug resistance. Test results were obtained from 73 samples from 38 individuals (31 baseline samples, 36 first-line failure samples, and six second-line failure samples). Four (13%) of the 31 baseline samples had mutations associated with resistance to nucleoside or nonnucleoside reverse transcriptase inhibitors (NRTIs and NNRTIs, respectively). Among the 36 first-line failure samples, 31 (86%) had NNRTI resistance mutations and 29 (81%) had lamivudine resistance mutations; only eight (22%) had other NRTI resistance mutations. None of the six individuals failing a second-line protease inhibitor (PI)-based regimen had PI resistance mutations. Six (16%) of the participants had discordant genotypic and phenotypic test results. Genotypic resistance to drugs included in first-line ART regimens was detected prior to treatment and among participants failing first-line ART. PI resistance was not detected in individuals failing second-line ART. Surveillance for transmitted and acquired drug resistance remains a priority for scale-up of ART.
PMCID: PMC3505045  PMID: 22443282
5.  Tax Gene Characterization of Human T-Lymphotropic Virus Type 1 Strains from Brazilian HIV-Coinfected Patients 
AIDS Research and Human Retroviruses  2012;28(12):1775-1778.
The tax gene of human T-lymphotropic virus type 1 (HTLV-1) diverges among isolates according to geographic regions and has been classified into two genotypes: taxA and taxB. In Brazil, taxA is the most prevalent genotype in symptomatic and asymptomatic carriers. Few studies have been conducted in HIV-infected patients. The present study characterized the tax gene (1059 bp) in 13 Brazilian HIV-1/HTLV-1-coinfected patients from the south and southeast regions. The results confirmed the transcontinental HTLV-1 subgroup A of the Cosmopolitan subtype and showed high nucleotide similarity both among Brazilian sequences and in relation to the ATK prototype (99.5% and 99.2%, respectively). Six nucleotide substitutions were highly conserved among isolates, ranging from 76.9% to 100%: C7401T, T7914C, C7920T, C7982T, G8231A, and A8367C. The presence of the Brazilian molecular signature of genotype taxA was confirmed in all of the isolates, and they clustered into two Latin American clusters, which confirms the double introduction of HTLV-1 in Brazil.
PMCID: PMC3505046  PMID: 22449200
6.  HIV Type 1 Viral Infectivity Factor and the RUNX Transcription Factors Interact with Core Binding Factor β on Genetically Distinct Surfaces 
AIDS Research and Human Retroviruses  2012;28(12):1543-1551.
Human immunodeficiency virus type 1 (HIV-1) requires the cellular transcription factor core binding factor subunit β (CBFβ) to stabilize its viral infectivity factor (Vif) protein and neutralize the APOBEC3 restriction factors. CBFβ normally heterodimerizes with the RUNX family of transcription factors, enhancing their stability and DNA-binding affinity. To test the hypothesis that Vif may act as a RUNX mimic to bind CBFβ, we generated a series of CBFβ mutants at the RUNX/CBFβ interface and tested their ability to stabilize Vif and impact transcription at a RUNX-dependent promoter. While several CBFβ amino acid substitutions disrupted promoter activity, none of these impacted the ability of CBFβ to stabilize Vif or enhance degradation of APOBEC3G. A mutagenesis screen of CBFβ surface residues identified a single amino acid change, F68D, that disrupted Vif binding and its ability to degrade APOBEC3G. This mutant still bound RUNX and stimulated RUNX-dependent transcription. These separation-of-function mutants demonstrate that HIV-1 Vif and the RUNX transcription factors interact with cellular CBFβ on genetically distinct surfaces.
PMCID: PMC3505047  PMID: 22725134
7.  Recombination Between Variants from Genital Tract and Plasma: Evolution of Multidrug-Resistant HIV Type 1 
AIDS Research and Human Retroviruses  2012;28(12):1766-1774.
Multidrug-resistant (MDR) HIV-1 presents a challenge to the efficacy of antiretroviral therapy (ART). To examine mechanisms leading to MDR variants in infected individuals, we studied recombination between single viral genomes from the genital tract and plasma of a woman initiating ART. We determined HIV-1 RNA sequences and drug resistance profiles of 159 unique viral variants obtained before ART and semiannually for 4 years thereafter. Soon after initiating zidovudine, lamivudine, and nevirapine, resistant variants and intrapatient HIV-1 recombinants were detected in both compartments; the recombinants had inherited genetic material from both genital and plasma-derived viruses. Twenty-three unique recombinants were documented during 4 years of therapy, comprising ∼22% of variants. Most recombinant genomes displayed similar breakpoints and clustered phylogenetically, suggesting evolution from common ancestors. Longitudinal analysis demonstrated that MDR recombinants were common and persistent, demonstrating that recombination, in addition to point mutation, can contribute to the evolution of MDR HIV-1 in viremic individuals.
PMCID: PMC3505048  PMID: 22364185
8.  Characterization of HIV Type 1 Envelope Sequence Among Viral Isolates Circulating in the Northern Region of Colombia, South America 
AIDS Research and Human Retroviruses  2012;28(12):1779-1783.
To characterize human immunodeficiency virus (HIV-1) strains circulating in the Northern region of Colombia in South America, sequences of the viral envelope C2V3C3 region were obtained from patients with different high-risk practices. Close to 60% of the sequences were predicted to belong to macrophage-tropic viruses, according to the positions of acidic amino acids and putative N-linked glycosylation sites. This is in agreement with the fact that most of the patients were recently diagnosed individuals. Phylogenic analysis then allowed assignment of all 35 samples to subtype B viruses. This same subtype was found in previous studies carried out in other Colombian regions. This study thus expands previous analyses with previously missing data from the Northern region of the country. The number and the length of the sequences examined also help to provide a clearer picture of the prevailing situation of the present HIV epidemics in this country.
PMCID: PMC3505049  PMID: 22482735
9.  CD4 T Cell Depletion Exacerbates Acute Mycobacterium tuberculosis While Reactivation of Latent Infection Is Dependent on Severity of Tissue Depletion in Cynomolgus Macaques 
AIDS Research and Human Retroviruses  2012;28(12):1693-1702.
CD4 T cells are believed to be important in protection against Mycobacterium tuberculosis, but the relative contribution to control of initial or latent infection is not known. Antibody-mediated depletion of CD4 T cells in M. tuberculosis-infected cynomolgus macaques was used to study the role of CD4 T cells during acute and latent infection. Anti-CD4 antibody severely reduced levels of CD4 T cells in blood, airways, and lymph nodes. Increased pathology and bacterial burden were observed in CD4-depleted monkeys during the first 8 weeks of infection compared to controls. CD4-depleted monkeys had greater interferon (IFN)-γ expression and altered expression of CD8 T cell activation markers. During latent infection, CD4 depletion resulted in clinical reactivation in only three of six monkeys. Reactivation was associated with lower CD4 T cells in the hilar lymph nodes. During both acute and latent infection, CD4 depletion was associated with reduced percentages of CXCR3+ expressing CD8 T cells, reported to be involved in T cell recruitment, regulatory function, and effector and memory T cell maturation. CXCR3+ CD8 T cells from hilar lymph nodes had more mycobacteria-specific cytokine expression and greater coexpression of multiple cytokines compared to CXCR3− CD8 T cells. CD4 T cells are required for protection against acute infection but reactivation from latent infection is dependent on the severity of depletion in the draining lymph nodes. CD4 depletion influences CD8 T cell function. This study has important implications for human HIV–M. tuberculosis coinfection.
PMCID: PMC3505050  PMID: 22480184
10.  Short Communication: Factors Influencing Time to CD4+ T Cell Counts >200 Cells/mm3 in HIV-Infected Individuals with CD4+ T Cell <50 Cells/mm3 at the Time of Starting Combination Antiretroviral Therapy 
AIDS Research and Human Retroviruses  2012;28(12):1594-1597.
We evaluated factors influencing time to CD4+ T cell counts >200 cells/mm3 in HIV-infected individuals with CD4+ T cell <50 cells/mm3 starting combination antiretroviral therapy (cART). We included a total of 29 patients on successful cART for more than 1 year. In a logistic regression model, higher pre-cART CD4+ T cell counts were significantly associated with shorter time to CD4+ T cell counts >200cells/mm3 in HIV-infected individuals with baseline CD4+ T cell <50 cells/mm3. In survival analysis, patients having higher pre-cART CD4+ T cell counts, especially 40–49 cells/mm3, were at significantly higher risk of achieving CD4+ T cell counts >200 cells/mm3.
PMCID: PMC3505051  PMID: 22632127
11.  Genetic Diversity and Naturally Polymorphisms in HIV Type 1 Integrase Isolates from Maputo, Mozambique: Implications for Integrase Inhibitors 
AIDS Research and Human Retroviruses  2012;28(12):1788-1792.
HIV proviral DNA integration into the host chromosome is carried out by integrase becoming an important target antiretroviral therapy. Raltegravir was the first integrase inhibitor approved for use in HIV therapy and elvitegravir is in the late phase of clinical development; both show good results in monotherapy studies and may be used worldwide for rescue therapy. In this work we analyzed 57 integrase sequences obtained from samples from drug-naive and first line regime-failing patients from Maputo, Mozambique, to evaluate the presence of natural polymorphisms and resistance mutations associated with raltegravir and elvitegravir. No major mutations conferring resistance to integrase inhibitors were found and polymorphic accessory mutations were solely observed in low frequency among subtype C sequences—L74M (3.4%), T97A (1.8%), and E157Q (1.8%)—suggesting that this new antiretroviral drug class will be effective in Mozambique providing a good perspective to the introduction of this class of drugs in that country.
PMCID: PMC3505052  PMID: 22497664
12.  Cellular and Humoral Immune Responses to Pandemic Influenza Vaccine in Healthy and in Highly Active Antiretroviral Therapy-Treated HIV Patients 
AIDS Research and Human Retroviruses  2012;28(12):1606-1616.
Influenza vaccination is recommended for HAART-treated HIV patients to prevent influenza illness and complications. Due to the known ability of T cells to mediate a broadly cross-reactive response, vaccination effectiveness in cell-mediated immune (CMI) response induction is a main objective in new influenza vaccination strategies. Nevertheless, data on CMI responses after pandemic vaccination in HIV subjects are still missing. In the present study, the ability of a single dose of adjuvanted pandemic influenza vaccine to induce humoral and CMI responses was compared in HAART-treated HIV patients and in healthcare workers. Healthcare workers (HCW, n=65) and HAART-treated HIV patients (HIV, n=67) receiving pandemic vaccination were enrolled and analyzed before (t0) and after (t1) vaccination. The analysis of strain-specific humoral response was performed by HAI assay; CMI against pandemic (A/H1N1/Cal/09) and seasonal (A/H1N1/Brisb/07 and A/H3N2/Brisb/07) strains was analyzed by ELISpot and intracellular staining followed by flow cytometry. Pandemic vaccination was effective in inducing both humoral and cell-mediated responses in HAART-treated HIV patients as well as in HCWs. A large fraction of both HCWs and HIV-infected patients showed a T cell response to the pandemic strain before vaccination, suggesting possible previous exposure to A/H1N1/pdm/09 and/or cross-reactive T cells. Notably, pandemic vaccine was also able to boost cross-reactive immune responses to seasonal strains. Finally, a weaker boost of both strain-specific and cross-reactive T cell immunity was found in individuals showing a higher baseline response. These data show the effectiveness of adjuvanted pandemic vaccine to induce both humoral and cellular (strain-specific and cross-reactive) immune responses in HIV patients similar to HCWs.
PMCID: PMC3505053  PMID: 22439734
13.  Sensitivity Changes over the Course of Infection Increases the Likelihood of Resistance Against Fusion but Not CCR5 Receptor Blockers 
AIDS Research and Human Retroviruses  2012;28(12):1584-1593.
As HIV-1 evolves over the course of infection, resistance against antiretrovirals may arise in the absence of drug pressure, especially against receptor and fusion blockers because of the extensive changes observed in the envelope glycoprotein. Here we show that viruses from the chronic phase of disease are significantly less sensitive to CCR5 receptor and fusion blockers compared to early infection variants. Differences in susceptibility to CCR5 antagonists were observed in spite of no demonstrable CXCR4 receptor utilization. No significant sensitivity differences were observed to another entry blocker, soluble CD4, or to reverse transcriptase, protease, or integrase inhibitors. Chronic as compared to early phase variants demonstrated greater replication when passaged in the presence of subinhibitory concentrations of fusion but not CCR5 receptor inhibitors. Fusion antagonist resistance, however, emerged from only one chronic phase virus culture. Because sensitivity to receptor and fusion antagonists is correlated with receptor affinity and fusion capacity, respectively, changes that occur in the envelope glycoprotein over the course of infection confer greater ability to use the CCR5 receptor and increased fusion ability. Our in vitro passage studies suggest that these evolving phenotypes increase the likelihood of resistance against fusion but not CCR5 receptor blockers.
PMCID: PMC3505054  PMID: 22650962
14.  Unusual Insertion and Deletion at Codon 67 and 69 of HIV Type 1 Subtype C Reverse Transcriptase Among First-Line Highly Active Antiretroviral Treatment-Failing South Indian Patients: Association with Other Resistance Mutations 
AIDS Research and Human Retroviruses  2012;28(12):1763-1765.
We report a high frequency of drug resistance mutations among patients with unusual insertions or deletions at the β3–β4 hairpin-loop-coding region of HIV-1 subtype C reverse transcriptase, during failure of first-line antiretroviral therapy containing only reverse transcriptase inhibitors in Chennai, India.
PMCID: PMC3505055  PMID: 22404052
15.  Short Communication: HIV Type 1 Accumulates in Influenza-Specific T Cells in Subjects Receiving Seasonal Vaccination in the Context of Effective Antiretroviral Therapy 
AIDS Research and Human Retroviruses  2012;28(12):1687-1692.
Whether or not HIV-1 continues to infect cells in individuals treated with effective antiretroviral therapy (ART) remains controversial. Here, we determined whether the redistribution of the HIV-1 proviral burden with respect to antigen specificity of CD4+ cells would provide evidence for ongoing infection cycles in vivo. HIV-1 preferentially infects antigen-stimulated CD4+ T cells. In the setting of prolonged effective ART, we postulated that if infection cycles were occurring, influenza-specific CD4+ T cells, activated by influenza vaccination, would preferentially accumulate proviral burden. Peripheral blood mononuclear cells (PBMCs) were collected from HIV-1-infected subjects who had been treated with effective ART for >5 years, before and after influenza vaccination. CD4+ T cells were sorted by antigen specificity and HIV-1 proviral burdens were determined. Levels of HIV-1 production upon in vitro antigenic stimulation were also measured. At baseline, influenza-specific CD4+ T cells carried higher HIV-1 proviral loads than HIV-1-p55-specific CD4+ T cells. Upon influenza vaccination we observed trends toward elevated levels of HIV-1 proviral DNA in influenza and HIV-1-p55-specific, but not tetanus toxoid or cytomegalovirus (CMV)-specific CD4+ T cells. Higher levels of HIV-1 virions were produced upon influenza stimulation in postvaccination as compared to baseline samples. While the trends toward increased proviral burdens in influenza-specific cells failed to reach statistical significance, our observation of disproportionately high levels of provirus in influenza-specific cells at baseline indicates that this may represent a real increase that is cumulative over multiple annual vaccinations. This has implications for the eradication of HIV-1 by adding to the evidence that the resting CD4+ T cell viral reservoir is continually replenished in ART-treated subjects.
PMCID: PMC3505056  PMID: 22734882
16.  Short Communication: Adhesion Pathways Utilized by HIV-Infected Lymphocytes 
AIDS Research and Human Retroviruses  2012;28(12):1557-1560.
We recently reported a novel adhesion pathway in lymphocytes that is mediated by cyclin-dependent kinase (Cdk) 4 activity and mediates lymphocyte interactions with endothelial matrix. We now demonstrate that HIV-infected lymphocytes also use Cdk4 to mediate spontaneous adhesion to fibronectin and endothelial matrix. We further demonstrate that HIV-infected lymphocytes require Rap-1 activity for phorbol-stimulated adhesion. Understanding adhesion pathways used by HIV-infected lymphocytes may lead to interventions to regulate aberrant adhesion and migration.
PMCID: PMC3505057  PMID: 22394260
17.  Short Communication: Emerging Transmitted HIV Type 1 Drug Resistance Mutations Among Patients Prior to Start of First-Line Antiretroviral Therapy in Middle and Low Prevalence Sites in China 
AIDS Research and Human Retroviruses  2012;28(12):1637-1639.
It is known that transmitted drug resistance (TDR) will most likely emerge in regions where antiretroviral therapy (ART) has been widely available for years. However, after a decade of rapid scale-up of ART in China, there are few data regarding TDR among HIV-infected patients prior to initiating first-line ART in China. A prospective, observational cohort study was performed at sentinel sites in five provinces or municipalities. Study participants were recruited at the county- or city-level centers for disease control (CDCs), during routine monitoring visits following referral from diagnosing parties (e.g., hospitals). Each province or municipality recruited 140 patients through sequential sampling throughout the 2011 calendar year. A total of 627 eligible subjects were included in the analysis. the median CD4+ cell count was 206 cells/ml at the baseline survey. The majority of patients (93.5%) had plasma HIV viral load ≥1,000 copies/ml. Of the 627 patients, 17 (2.7%) had drug resistance mutations for any type of HIV drugs. The prevalence of drug resistance mutations to nonnucleoside reverse transcriptase inhibitor (NNRTI) drugs (8/627, 1.3%) was higher than to nucleoside reverse transcriptase inhibitor (NRTI) drugs (5/627, 0.8%) and protease inhibitor (PI) drugs (4/627, 0.6%). A logistic regression model showed that the only predictive factor was the route of infection through homosexual intercourse, i.e., men who have sex with men (MSM) status. As HIV prevalence is rising rapidly among Chinese MSM, it is essential to continue surveying this risk group and related high-risk populations with low awareness of HIV, and to develop new public health interventions that help to reduce the spread of drug-resistant HIV.
PMCID: PMC3505058  PMID: 22822770
18.  Short Communication: HIV Type 1 Escapes Inactivation by Saliva via Rapid Escape into Oral Epithelial Cells 
AIDS Research and Human Retroviruses  2012;28(12):1574-1578.
Saliva contains anti-HIV-1 factors, which show unclear efficacy in thwarting mucosal infection. When incubated in fresh, unfractionated whole saliva, infectious HIV-1 IIIb and BaL (X4- and R5-tropic, respectively) persisted from 4 to at least 30 min in a saliva concentration-dependent manner. In salivary supernatant for up to 6 h, both infectious HIV-1 strains “escaped” into immortalized oral epithelial cells; infectious BaL showed selectively enhanced escape in the presence of saliva. Fluorescently labeled HIV-1 virus-like particles entered oral epithelial cells within minutes of exposure. Using a previously unrecognized mechanism, therefore, strains of HIV-1 escape inactivation by saliva via rapid uptake into oral epithelial cells.
PMCID: PMC3505059  PMID: 22077822
19.  A gp41-Based Heteroduplex Mobility Assay Provides Rapid and Accurate Assessment of Intrasubtype Epidemiological Linkage in HIV Type 1 Heterosexual Transmission Pairs 
AIDS Research and Human Retroviruses  2012;28(12):1745-1755.
A critical step in HIV-1 transmission studies is the rapid and accurate identification of epidemiologically linked transmission pairs. To date, this has been accomplished by comparison of polymerase chain reaction (PCR)-amplified nucleotide sequences from potential transmission pairs, which can be cost-prohibitive for use in resource-limited settings. Here we describe a rapid, cost-effective approach to determine transmission linkage based on the heteroduplex mobility assay (HMA), and validate this approach by comparison to nucleotide sequencing. A total of 102 HIV-1-infected Zambian and Rwandan couples, with known linkage, were analyzed by gp41-HMA. A 400-base pair fragment within the envelope gp41 region of the HIV proviral genome was PCR amplified and HMA was applied to both partners' amplicons separately (autologous) and as a mixture (heterologous). If the diversity between gp41 sequences was low (<5%), a homoduplex was observed upon gel electrophoresis and the transmission was characterized as having occurred between partners (linked). If a new heteroduplex formed, within the heterologous migration, the transmission was determined to be unlinked. Initial blind validation of gp-41 HMA demonstrated 90% concordance between HMA and sequencing with 100% concordance in the case of linked transmissions. Following validation, 25 newly infected partners in Kigali and 12 in Lusaka were evaluated prospectively using both HMA and nucleotide sequences. Concordant results were obtained in all but one case (97.3%). The gp41-HMA technique is a reliable and feasible tool to detect linked transmissions in the field. All identified unlinked results should be confirmed by sequence analyses.
PMCID: PMC3505061  PMID: 22587371
20.  Polymorphisms of the SAMHD1 Gene Are Not Associated with the Infection and Natural Control of HIV Type 1 in Europeans and African-Americans 
AIDS Research and Human Retroviruses  2012;28(12):1565-1573.
The HIV-1 restriction factor SAM domain and HD domain-containing protein 1 (SAMHD1) blocks HIV-1 infection in human myeloid cells. Mutations in the SAMHD1 gene are associated with rare genetic diseases including Aicardi–Goutieres syndrome. However, it is unknown whether polymorphisms of SAMHD1 are associated with infection and natural control of HIV-1 in humans. Our objective was to determine whether the expression of SAMHD1 mRNA is affected by common single nucleotide polymorphisms (SNPs) in SAMHD1 and whether the SNPs are associated with HIV-1 infection status. Using a tagging SNP approach, we determined the association between eight tagging SNPs in SAMHD1 and the mRNA expression in B-lymphocyte cell lines from 70 healthy white donors. We identified one SNP (rs1291142) that was significantly associated with SAMHD1 mRNA expression, with minor allele carriers having 30% less mRNA levels (p=0.015). However, after analyzing the published genome-wide association study data of 857 HIV-1 controllers and 2088 HIV-1 progressors from the European and African-American cohorts, we did not find a significant association between SNPs in SAMHD1 and HIV-1 infection status, including SNP rs1291142 (p>0.05). We also observed 2- to 6-fold variations of SAMHD1 mRNA levels in primary B-lymphocytes, CD4+ T-lymphocytes, and CD14+ monocytes from five healthy donors. Our results suggest that common regulatory polymorphism(s) exist in the SAMHD1 gene that affects its mRNA expression in B-lymphocyte cell lines from healthy whites. However, polymorphisms of SAMHD1 are unlikely to contribute to the infection and natural control of HIV-1 in European and African-American individuals.
PMCID: PMC3505062  PMID: 22530776
21.  The Impact of Impaired Kidney Function and HIV Infection on the Risk of Anemia 
AIDS Research and Human Retroviruses  2012;28(12):1666-1671.
Chronic kidney disease and HIV infection both independently increase the risk of anemia. It is not known if individuals with both HIV infection and kidney dysfunction are at greater than expected risk of anemia resulting from the combined effect of these factors. Men from the Multicenter AIDS Cohort Study with AIDS-free time after 1996 were included in the analysis if they had an initial hemoglobin value greater than 13 g/dl and available serum creatinine measurements for the estimation of glomerular filtration rate. Hemoglobin data were fit parametrically using a linear mixed effects model and effects of medication use on hemoglobin levels were removed using censoring methods. The effect of both HIV infection and glomerular filtration rate less than 60 ml/min/1.73 m2 on the mean hemoglobin value was assessed. The risk of having anemia (hemoglobin level falling below 13 g/dl) was estimated. There were 862 HIV-infected and 1,214 HIV-uninfected men who contributed to the analysis. Hemoglobin values across all 17,341 person-visits, adjusting for age, were generally lower in HIV-infected AIDS-free men with impaired kidney function by −0.22 g/dl (95% CI: −0.42, −0.03) compared to men with either HIV infection or impaired kidney function, but not both. HIV-infected AIDS-free men with impaired kidney function have a higher risk of anemia by 1.2% compared to HIV-uninfected men with normal kidney function. Comorbid conditions and medication use did not explain this increase in risk. HIV infection and impaired kidney function have a combined impact on lowering hemoglobin levels, resulting in a higher risk of anemia.
PMCID: PMC3505063  PMID: 22632256
22.  Human Papillomavirus Infection in Men Who Have Sex with Men in Lima, Peru 
AIDS Research and Human Retroviruses  2012;28(12):1734-1738.
Human papillomavirus (HPV) infection among men who have sex with men (MSM) is the primary risk factor for anal cancer. Of 105 Peruvian MSM examined, 77.1% were infected with HPV; of these 79.0% were coinfected with two or more types and 47.3% were infected by a carcinogenic type. HPV types 53, 6, 16, and 58 were the most frequent HPV infections detected. High-risk HPV type infection was associated with sex work, HIV status, and having rectal chlamydial or gonorrheal infection. These findings support broadening HPV vaccine coverage and increasing surveillance for the development of cancer in MSM infected with HPV.
PMCID: PMC3505064  PMID: 22519744
23.  Short Communication: Initiation of an Abacavir-Containing Regimen in HIV-Infected Adults Is Associated with a Smaller Decrease in Inflammation and Endothelial Activation Markers Compared to Non-Abacavir-Containing Regimens 
AIDS Research and Human Retroviruses  2012;28(12):1561-1564.
Abacavir has been associated with myocardial infarction in several studies. This may be related to inflammation and endothelial cell activation. We compared changes in inflammation and endothelial activation markers between antiretroviral-naive adults initiating zidovudine, lamivudine, abacavir, and nonnucleoside reverse transcriptase inhibitor (NNRTI) or this regimen without abacavir. Changes in soluble tumor necrosis factor receptors-I, -II (sTNFR-I, -II), high sensitivity C-reactive protein, and soluble vascular cell adhesion molecule-1 (sVCAM-1) from baseline (pre-ART) to a second time point about 24 weeks after initiating antiretroviral therapy (ART) were compared between groups using multivariable linear regression. A total of 37 met eligibility criteria; 12 received abacavir. The median (interquartile range) age was 37 years (27–45). Most were men (32/37), African-American (15/37), or white (15/37). The median nadir CD4+ and baseline HIV-1 RNA were 230 cells/mm3 (180–301) and 82,642 copies/ml (34,400–204,703). In all, 15/30 smoked, 7/37 had hypertension, 1/37 had diabetes, and 1/37 had hyperlipidemia. None had coronary or renal disease. Changes in CD4+ and HIV-1 RNA level and timing of stored samples with regard to ART initiation were not different between groups. In univariable analysis, log transformed percent change in sTNFR-I (p=0.05) and -II (p=0.04) showed significant between-group differences and trended toward significance for sVCAM-1 (p=0.08). These markers decreased less in the abacavir group. After adjustment for confounders, significantly less decrease for sTNFR-II and sVCAM-1 was seen for those receiving the abacavir-containing regimen. When taken with an NNRTI, abacavir induced a smaller decrease in inflammation biomarkers in this cohort, suggesting a possible proinflammatory effect of this nucleoside analogue.
PMCID: PMC3505065  PMID: 22463776
24.  Short Communication: Risk of Elevated Total Cholesterol/High-Density Lipoprotein Cholesterol Ratio After Antiretroviral Therapy in HIV/Hepatitis C Virus Patients 
AIDS Research and Human Retroviruses  2012;28(12):1552-1556.
Dyslipidemia from highly active antiretroviral therapy (HAART) use has been reported to be less severe among persons with HIV and hepatitis C (HCV) compared to those with HIV monoinfection. However, the effect on lipoprotein ratios is less clear. The total cholesterol/high-density lipoprotein ratio (TC/HDL-C ratio) is a robust measure of cardiovascular disease (CVD) risk but has not been examined in the context of HIV/HCV-coinfected patients. We compared the TC/HDL-C ratio before HAART initiation and after at least 6 months on HAART between patients monoinfected with HIV and coinfected with HIV and HCV. Pre- and post-HAART TC, HDL-C, and non-HDL-C were also assessed. Although TC, HDL-C, and non-HDL-C significantly increased after HAART initiation in both HIV and HIV/HCV patients, the TC/HDL-C ratio did not. In addition, although the pre- and post-HAART TC, HDL-C, non-HDL-C, and TC/HDL-C ratio were significantly different between HIV and HIV/HCV patients, the magnitude in the change from pre- to post-HAART was not significantly different between infection groups. These results persisted after controlling for age, sex, race, current pharmacotherapy for lipoproteins, body mass index, and current CD4 cell count. The magnitude of change in the TC/HDL-C ratio after HAART initiation is not significantly different between HIV and HIV/HCV patients, suggesting subsequent CVD risk in HIV/HCV patients may be greater than currently appreciated.
PMCID: PMC3505066  PMID: 22380598
25.  New Subtypes and Genetic Recombination in HIV Type 1-Infecting Patients with Highly Active Antiretroviral Therapy in Peru (2008–2010) 
AIDS Research and Human Retroviruses  2012;28(12):1712-1722.
HIV-1 subtype B is the most frequent strain in Peru. However, there is no available data about the genetic diversity of HIV-infected patients receiving highly active antiretroviral therapy (HAART) here. A group of 267 patients in the Peruvian National Treatment Program with virologic failure were tested for genotypic evidence of HIV drug resistance at the Instituto Nacional de Salud (INS) of Peru between March 2008 and December 2010. Viral RNA was extracted from plasma and the segments of the protease (PR) and reverse transcriptase (RT) genes were amplified by reverse transcriptase polymerase chain reaction (RT-PCR), purified, and fully sequenced. Consensus sequences were submitted to the HIVdb Genotypic Resistance Interpretation Algorithm Database from Stanford University, and then aligned using Clustal X v.2.0 to generate a phylogenetic tree using the maximum likelihood method. Intrasubtype and intersubtype recombination analyses were performed using the SCUEAL program (Subtype Classification by Evolutionary ALgo-rithms). A total of 245 samples (91%) were successfully genotyped. The analysis obtained from the HIVdb program showed 81.5% resistance cases (n=198). The phylogenetic analysis revealed that subtype B was predominant in the population (98.8%), except for new cases of A, C, and H subtypes (n=4). Of these cases, only subtype C was imported. Likewise, recombination analysis revealed nine intersubtype and 20 intrasubtype recombinant cases. This is the first report of the presence of HIV-1 subtypes C and H in Peru. The introduction of new subtypes and circulating recombinants forms can make it difficult to distinguish resistance profiles in patients and consequently affect future treatment strategies against HIV in this country.
PMCID: PMC3508545  PMID: 22559065

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