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1.  Prevalence and Correlates of Sexual Risk Behaviors Among Drug Users in Western China: Implications for HIV Transmission 
Abstract
The prevalence and correlates of sexual risk behaviors among drug users in western China and the implications for HIV transmission in this population are described. A cross-sectional survey of male drug users was conducted in methadone maintenance therapy clinics and detoxification centers in three western provinces of China between September 2009 and December 2010. Participants in the study completed a questionnaire about demographics, HIV/AIDS knowledge, drug use history, sexual risk behaviors, and other psychosocial variables. Factors associated with HIV sexual risk behaviors were identified by multiple logistic regression analysis. Of 1,304 drug users surveyed, nearly 54% never used condoms during sexual intercourse with a spouse or cohabitant, and this behavior was associated with coming from Chongqing (OR=1.86, p<0.05), being aged 36 and older (OR=5.03, p<0.05), being married or cohabiting (OR=1.68, p<0.05), having first taken drugs at age 30 and above (OR=1.80, p<0.05), and having received AIDS advice or detection from authorities in the past year (OR=1.95, p<0.05). Twenty-six percent had had sex with casual sexual partners in the past year, and this behavior was associated with being married or cohabiting (OR=0.30, p<0.05), first taking drugs at age 31 and above (OR=0.42, p<0.05), and receiving AIDS advice or HIV detection from authorities in the past year (OR=0.70, p<0.05). About 34% never used a condom when having sex with casual sexual partners, and this behavior was associated with coming from Guangxi (OR=2.81, p<0.05) or Chongqing (OR=2.73, p<0.05). Almost 14% had had commercial sex in the past year, and this behavior was associated with coming from Guangxi (OR=6.26, p<0.05) or Chongqing (OR=5.44, p<0.05) and having exchanged needles or received clean needles from the Needle Exchange Centers in the past year (OR=2.76, p<0.05). Nearly 23% had never used condoms when having commercial sex, and this behavior was associated with having received free condoms from authorities in the past year (OR=0.26, p<0.05). Sexual risk behaviors among drug users in Guangxi, Chongqing, and Xinjiang are common. Additional intervention strategies are needed to control the spread of HIV in this population.
doi:10.1089/aid.2012.0272
PMCID: PMC3607904  PMID: 23210514
2.  Short Communication: HIV Prevalence and Risk Behavior Among Injection Drug Users and Their Sex Partners in Two Russian Cities 
Abstract
The HIV epidemic in Russia remains concentrated mostly among injection drug users (IDUs). Little is known about the extent to which sexual partnerships are the bridge between IDUs and the general population and create the potential for generalizing the epidemic. IDUs in two Russian cities, Novosibirsk and Ivanovo (N=593), were recruited via respondent-driven sampling. A modified one-step snowball strategy was used to recruit IDU's sex partners who do not themselves use drugs (PIDU, N=82). Sexual behaviors of all participants were assessed using an interviewer-administered questionnaire. All participants provided blood specimens for HIV and hepatitis C virus (HCV) testing. HIV and HCV prevalence among IDUs was 34.0% and 44.4% in Ivanovo and 3.8% and 54.3% in Novosibirsk. HIV prevalence among PIDUs was 6.8% in Ivanovo and 8.7% in Novosibirsk. In both cities large proportions of IDUs reported sexual partnerships with non-IDUs—49.7% in Ivanovo vs. 62.7% in Novosibirsk (p≤0.001) and fewer than one in four IDUs reported constant condom use in such partnerships. This pilot study shows that two IDU populations with a significantly different HIV prevalence both form sexual partnerships with non-IDUs and practice unsafe sexual behavior within such types of partnerships. However, the proportion of PIDUs who form partnerships with other non-IDUs that therefore could lead to a generalization of the epidemic is very different between the two cities and this difference needs to be considered when estimating the spread of HIV into the general population. Unsafe sexual behavior and HIV testing should be specific targets for prevention activities for IDUs and their sex partners in Russia.
doi:10.1089/aid.2012.0161
PMCID: PMC3607905  PMID: 23186172
3.  Augmentation of Hepatitis B Virus-Specific Cellular Immunity with Programmed Death Receptor-1/Programmed Death Receptor-L1 Blockade in Hepatitis B Virus and HIV/Hepatitis B Virus Coinfected Patients Treated with Adefovir 
Abstract
The immunological parameters leading to viral persistence in chronic hepatitis B (CHB) are not clearly established. We analyzed HBV-specific immunoregulatory mechanisms in HIV-infected and HIV-uninfected HBeAg+ CHB patients to determine (1) the roles of immunoregulatory pathways, (2) the effect of anti-HBV therapy on immunoregulatory pathways, and (3) the role of immunomodulatory therapy to overcome the effect of T regulatory cells (Tregs, CD4+CD25+FoxP3+) in HBV-infected individuals. A prospective, double blind, randomized, placebo-controlled trial treated HBV (HIV+/–)-infected patients with adefovir 10 mg daily or placebo for 48 weeks. HBV viral load (VL), immunophenotying, and functional studies were performed at multiple time points. Suppression of HBV VL with adefovir leads to decreased peripheral expansion of Tregs. While declining, Tregs significantly inhibit cytokine-secreting HBV-specific CD8+ T cell responses over 48 weeks of anti-HBV adefovir therapy (p<0.05). A large proportion of these Tregs express programmed death receptor-1 (PD-1), blockade of which in vitro leads to improved cytokine-secreting HBV-specific CD8+ T cell responses, particularly in HIV/HBV-coinfected patients (p<0.05). Peripheral expansion of Treg levels correlated with HBV viral load and decreased HBV-specific CD8+ T cells. PD-1 blockade increased survival of HBV-specific CD8+ T cells, removing the inhibitory effect of PD-1+ peripheral Tregs. Hence therapies involving PD-1 blockade in combination with directly acting antivirals should be investigated to reduce the need for life-long directly acting antiviral therapy.
doi:10.1089/aid.2012.0320
PMCID: PMC3607907  PMID: 23259453
4.  Phylogenetic Analysis of Near Full-Length HIV Type 1 Genomic Sequences from 21 Korean Individuals 
Abstract
The Korean subclade of subtype B (KSB) is the most prevalent HIV-1 strain found in Korea. To date, only two near full-length HIV-1 sequences from Korean patients have been reported. Here, we analyzed a total of 24 near full-length genomes of HIV-1 strains that were isolated from 17 antiretroviral therapy (ART)-naive patients and four ART-exposed patients. Proviral DNA from peripheral blood mononuclear cells was PCR amplified and directly sequenced. Phylogenetic analyses were used to classify viruses from 19 patients as KSB, from one patient as subtype B, from one patient as subtype D, and three viruses from one patient as CRF02_AG. All KSB viruses demonstrated TAAAA instead of TATAA at the TATA box in the LTR. Of the 19 KSB patients, their sequence identities at the nucleotide level ranged from 89.8% to 97.1% from the lowest env gene to the highest pol gene. Other than the CRF02_AG viruses, no recombination events were noted in any of the 19 KSB patients, which is consistent with our previous studies on the pol, vif, and nef genes. Except for one strain, all of the strains were classified as non-syncytium-inducing strains. This is the first report to describe near full-length KSB.
doi:10.1089/aid.2012.0298
PMCID: PMC3607908  PMID: 23199052
5.  Feline Glycoprotein A Repetitions Predominant Anchors Transforming Growth Factor Beta on the Surface of Activated CD4+CD25+ Regulatory T Cells and Mediates AIDS Lentivirus-Induced T Cell Immunodeficiency 
Abstract
Using the feline immunodeficiency virus (FIV) model for AIDS-lentivirus infection, our laboratory has previously demonstrated that T regulatory (Treg) cell-mediated immune T and B cell dysfunction contributes to lentivirus persistence and chronic disease through membrane bound transforming growth factor beta (mTGFb). Studying Treg cells in the context of infection has been problematic as no inducible marker for activated Treg cells had been identified. However, recent reports in human Treg studies have described a novel protein, glycoprotein A repetitions predominant (GARP), as a unique marker of activated human Treg cells that anchors mTGFb. Herein we extend these studies to the feline Treg system, identifying feline GARP and demonstrating that human and feline GARP proteins are homologous in structure, expression pattern, and ability to form a complex with TGFb. We further demonstrate that GARP and TGFb form a complex on the surface of activated Treg cells and that these GARP+TGFb+ Treg cells are highly efficient suppressor cells. Analysis of expression of this Treg activation marker in the FIV-AIDS model reveals an up-regulation of GARP expressing Treg cells during chronic FIV infection. We demonstrate that the GARP+ Treg cells from FIV-infected cats suppress T helper cells in vivo and that blocking GARP or TGFb eliminates this suppression. These data suggest that GARP is expressed in complex with TGFb on the surface of activated Treg cells and plays an important role in TGFb+ Treg-mediated T cell immune suppression during lentivirus infection.
doi:10.1089/aid.2012.0322
PMCID: PMC3607965  PMID: 23373523
6.  Short Communication: Synergism Between a CD4-Mimic Peptide and Antibodies Elicited by a Constrained V3 Peptide 
Abstract
Due to the different mechanisms HIV-1 has evolved to escape from a neutralizing antibody response it has been extremely challenging to develop an effective anti-HIV-1 vaccine. The V3 region of the gp120 HIV-1 envelope glycoprotein has been considered as one of the possible targets for an anti-HIV vaccine. It is well known that the V3 region of gp120 is at least partially masked in circulating strains and becomes exposed only after CD4 binding. However, when the virus is bound to surface CD4, steric hindrance prevents effective neutralization by V3-directed antibodies. Here we have used a 27-residue CD4-mimetic peptide in combination with immune sera elicited by an optimally constrained V3 peptide to enhance neutralization of a panel of clade B viruses. We observed strong synergism between the immune sera and the CD4-mimetic in the neutralization of tier 1 and a representative tier 2 clade B virus suggesting that the constrained V3 peptide immunogen correctly mimics the V3 conformation even in tier 2 clade B viruses. This synergy should improve the potential of CD4-mimetic compounds for preexposure prophylaxis and in the treatment of HIV-1-infected patients who usually manifest high titers of V3-directed antibodies. Moreover, constrained V3 immunogens elicit immune sera that may neutralize HIV in synergy with CD4 binding site antibodies that expose V3 and the coreceptor binding site.
doi:10.1089/aid.2012.0189
PMCID: PMC3607968  PMID: 23176398
7.  Effect of Persistency of First-Line HIV Antiretroviral Therapy on Clinical Outcomes 
Abstract
Persistency is the time from initiation to discontinuation of therapy. Previous research has described factors that affect the persistency of initial antiretroviral therapy (ART); however, the impact of persistency on clinical outcomes is unknown. A retrospective study was conducted of treatment-naive HIV patients initiating ART between January 1, 2000 and December 31, 2010 at an academic medical center. Descriptive statistics and Cox proportional hazards regression models with persistency as a time‐varying covariate were fit for (1) immunologic failure (subsequent CD4 lower than initial CD4); (2) development of an opportunistic infection (OI) or malignancy; and (3) mortality. Analyses were repeated with an interaction term of persistency (per 180 days) and time (before and after 1 year of ART). Among 879 patients who started ART, the mean age was 38 years (±10) and most patients were racial/ethnic minority (59%), males (80%), and with baseline CD4 <200 cells/mm3 (52%). There were 100 deaths, 94 OIs/malignancy, and 183 immunologic failures; the mean persistency=723 days. In multivariable modeling, increased persistency decreased the overall and long-term hazard for immunologic failure (0.84 per 180 additional days; 0.70–1.00; 0.045). Increased persistency exhibited a potential trend toward decreased hazard for the occurrence of OI/malignancy (0.91; 0.80–1.03; 0.124) overall and after 1 year. Persistency exhibited a trend toward less risk of mortality in the first year of ART (0.42; 0.17–1.06; 0.067). In this study of the relationship between initial ART persistency and clinical outcomes, increased persistency was associated with a decreased hazard for the development of immunologic failure, a trend toward a decreased hazard for OI/malignancy, and a trend toward a decreased risk of first year mortality. Given these findings, the relationship between persistency and clinical outcomes merits further study.
doi:10.1089/aid.2012.0241
PMCID: PMC3607971  PMID: 23151191
8.  The Design of Single-Arm Clinical Trials of Combination Antiretroviral Regimens for Treatment-Naive HIV-Infected Patients 
Abstract
Single-arm clinical trials are useful to evaluate antiretroviral regimens in certain populations of HIV-infected treatment-naive patients for whom a randomized controlled trial is not feasible or desirable. They can also be useful to establish initial estimates of efficacy and safety/tolerability of novel regimens to inform the design of large phase III trials. In this article, we discuss key design considerations for such single-arm studies.
doi:10.1089/aid.2012.0180
PMCID: PMC3607972  PMID: 23228206
9.  Distinct HIV Type 1 Strains in Different Risk Groups and the Absence of New Infections by Drug-Resistant Strains in Lithuania 
Abstract
To analyze HIV-1 genotypes in Lithuania and the transmission of drug-resistant viruses, HIV-1 sequences were obtained from 138 individuals, who were diagnosed as HIV-1 infected in 1990–2008 and represented all major risk groups. Subtype A strains, dominating in the former Soviet Union (90% of cases), were found in 60% of individuals, followed by subtype B (22%) and CRF03_AB (12%) strains. The remaining 7% of the strains included variants belonging to subtype C, CRF01_AE, CRF02_AG, more complex recombinant forms, and strains that could not be reliably genotyped. Analysis of virus genotypes per risk group revealed the circulation of distinct HIV-1 strains in different risk groups: subtype A viruses were present in 82% of injecting drug users (IDUs), but less than a half of heterosexually infected individuals and cases with unknown transmission route, and none of men having sex with men (MSM). We observed no mutations causing drug resistance among 27 newly diagnosed HIV-1 cases.
doi:10.1089/aid.2012.0312
PMCID: PMC3607974  PMID: 23186249
10.  Identification of a Novel Binding Site Between HIV Type 1 Nef C-Terminal Flexible Loop and AP2 Required for Nef-Mediated CD4 Downregulation 
Abstract
HIV-1 Nef is an accessory protein necessary for HIV-1 virulence and rapid AIDS development. Nef promotes viral replication and infection by connecting CD4 and several other cell surface receptors to the clathrin adaptor protein AP2, resulting in the internalization and degradation of the receptors interacting with Nef. We investigated how Nef can mediate constitutive receptor endocytosis through the interaction of the dileucine motif in its C-terminal flexible loop (C-loop) with AP2, whereas AP2 binding of the transmembrane receptors usually results in an equilibrated (recycled) endocytosis. Our results indicated that in addition to the dileucine motif, there is a second motif in the Nef C-loop involved in the Nef–AP2 interaction. Nef-mediated CD4 downregulation was impaired when the residue in the hydrophobic region in the Nef C-loop (LL165HPMSLHGM173) was mutated to a basic residue K/R or an acidic residue E/D or to the rigid residue P, or when M168L170, L170H171, or G172M173 was mutated to AA. A pull-down assay indicated that AP2 was not coprecipitated with Nef mutants that did not downregulate CD4. Molecular modeling of the Nef C-terminal flexible loop in complex with AP2 suggests that M168L170 occupies a pocket in the AP2 σ2 subunit. Our data suggest a new model in the Nef–AP2 interaction in which the hydrophobic region in the Nef C-loop with the dileucine (L164L165) motif and M168L170 motif binds to AP2(σ2), while the acidic motif E174 and D175 binds to AP2(α), which explains how Nef through the flexible loop connects CD4 to AP2 for constitutive CD4 downregulation.
doi:10.1089/aid.2012.0286
PMCID: PMC3903168  PMID: 23151229
11.  Frequent Intratype Neutralization by Plasma Immunoglobulin A Identified in HIV Type 2 Infection 
Abstract
Human immunodeficiency virus type 2 (HIV-2) is less transmissible and less pathogenic compared to HIV-1 and, when matched for CD4+ T cell count, the plasma viral load in HIV-2-infected individuals is approximately one log lower than in HIV-1-infected individuals. The explanation for these observations is elusive, but differences in virus controlling immunity generated in the two infections may be contributing factors. In the present study, we investigated neutralization by immunoglobulin A (IgA), in parallel with IgG, purified from plasma of HIV-1, HIV-2, and HIV-1/HIV-2 dually (HIV-D) infected individuals. Neutralization was analyzed against HIV-1 and HIV-2 isolates using a plaque reduction assay. In HIV-2 infection, intratype-specific neutralization by IgA was frequently detected, although at a lesser magnitude then the corresponding IgG neutralizing titers. In contrast, neutralization by IgA could rarely be demonstrated in HIV-1 infection despite similar plasma IgA levels in both infections. In addition, IgA and IgG of HIV-D plasma neutralized the HIV-2 isolate more potently than the HIV-1 isolate, suggesting that the difference between neutralizing activity of plasma IgA and IgG depends on the virus itself. Taken together, these findings suggest that both IgA and IgG add to the potent intratype neutralizing activity detected in HIV-2 plasma, which may contribute to virus control in HIV-2 infection.
doi:10.1089/aid.2012.0219
PMCID: PMC3581020  PMID: 23088167
12.  Darunavir Is a Good Third-Line Antiretroviral Agent for HIV Type 1-Infected Patients Failing Second-Line Protease Inhibitor-Based Regimens in South India 
Abstract
Eleven protease mutations have been associated with reduced susceptibility to darunavir. In this study of 87 HIV-1-infected patients experiencing virological failure to second-line regimens containing protease inhibitors boosted with ritonavir (viral load >1,000 HIV RNA copies/ml), we observed a low prevalence (3%) of ≥3 darunavir resistance-associated mutations, indicating that this drug may be a good option for third-line antiretroviral therapy in southern India.
doi:10.1089/aid.2011.0334
PMCID: PMC3581023  PMID: 23045961
13.  Depot Medroxyprogesterone Acetate Increases Immune Cell Numbers and Activation Markers in Human Vaginal Mucosal Tissues 
Abstract
The relationship between exogenous contraceptive hormones and permissiveness of the female genital tract to human immunodeficiency virus type 1 (HIV-1) is the subject of renewed debate. To better characterize the effect of depot medroxyprogesterone acetate (DMPA) on HIV-1 cellular targets and epithelial integrity in the vagina, we compared leukocyte populations, markers of activation and proliferation, and the density of intercellular junctional proteins in the vaginal epithelium of women during the follicular and luteal phases of the menstrual cycle and approximately 12 weeks after receiving a DMPA injection. This prospective cohort study involved 15 healthy women. Vaginal biopsies were obtained in the follicular and luteal phases of the menstrual cycle, and approximately 12 weeks following a 150-mg intramuscular injection of DMPA. Leukocyte populations, activation phenotype, and epithelial tight junction and adherens proteins were evaluated by immunohistochemistry. After receiving DMPA, the numbers of CD45, CD3, CD8, CD68, HLA-DR, and CCR5 bearing immune cells were significantly (p<0.05) increased in vaginal tissues, compared to the follicular and/or luteal phases of untreated cycles. There were no significant differences in immune cell populations between the follicular and luteal phases of the control cycle. There were also no statistically significant differences in epithelial thickness and density of epithelial tight junction and adherens proteins among the follicular, luteal, and post-DMPA treatment sampling points. In this pilot study, vaginal immune cell populations were significantly altered by exogenous progesterone, resulting in increased numbers of T cells, macrophages, and HLA-DR- and CCR5-positive cells.
doi:10.1089/aid.2012.0271
PMCID: PMC3581024  PMID: 23189932
14.  The Potent Human Immunodeficiency Virus Type 1 (HIV-1) Entry Inhibitor HR212 Blocks Formation of the Envelope Glycoprotein gp41 Six-Helix Bundle 
Abstract
HR212, a recombinant protein composed of the heptad repeat, is a rationally designed human immunodeficiency virus type 1 (HIV-1) fusion inhibitor. This protein can be easily produced by Escherichia coli at a low cost. Previously, studies indicated that HR212 can efficiently inhibit the entry and replication of both laboratory and clinical HIV-1 strains, and this protein is more stable and less sensitive to proteinases than T20. The procedure of HIV-1 entry into the host cells can be divided into three main steps: gp120–CD4 interactions, coreceptor binding, and gp41 six-helix bundle formation and subsequent membrane fusion. The present study demonstrates that HR212 does not block gp120–CD4 binding or interfere with binding to the coreceptors CXCR4 and CCR5. Instead, HR212 efficiently blocks the six-helix bundle formation between peptides derived from the N-terminal heptad repeat (NHR) and the C-terminal heptad repeat (CHR) region of gp41. Fluorescence native polyacrylamide gel electrophoresis (FN-PAGE) indicated that HR212 could form a complex with peptide N36 to block gp41 fusogenic core formation. These results suggest that HR212 inhibits HIV-1 entry by targeting the NHR region of gp41. Therefore, HR212 can potentially be developed as a novel, high-efficiency, specific HIV-1 entry inhibitor.
doi:10.1089/aid.2012.0059
PMCID: PMC3581026  PMID: 23308369
15.  Plasmacytoid Dendritic Cell Number and Responses to Toll-Like Receptor 7 and 9 Agonists Vary in HIV Type 1-Infected Individuals in Relation to Clinical State 
Abstract
In HIV-1 infection, plasmacytoid dendritic cell (PDC) numbers and function are decreased. No detailed comparisons of PDC responses to various stimuli in HIV-1-infected patients are available. Using for the first time purified PDCs, we compared PDC responses [interferon (IFN)-α production/cell] to various stimuli in a large number (n=48) of HIV-1-infected patients and healthy volunteers (n=19). Toll-like receptor (TLR)7- and TLR9-induced expression of PDC surface activation and maturation markers was also compared in the two populations. We have confirmed that PDC number coincides with CD4+ T cell counts and clinical state. Notably, we have shown that a direct association of PDC function in terms of IFN-α production/cell exists with PDC numbers and CD4+ cell counts when PDCs are exposed to a TLR9 ligand and HIV-infected cells, but not with a TLR7 ligand. Moreover, in the HIV-infected subjects but not the healthy controls, the magnitude of IFN-α release per PDC in response to the TLR7 ligand is significantly (p<0.01) lower than that to the TLR9 ligand. However, in both study populations, the TLR7 stimulation in comparison to TLR9 stimulation induced higher expression of PDC surface activation and maturation markers and significantly (p<0.05) decreased the expression of BDCA-2, a negative regulator of interferon. Furthermore, the cross-ligation of BDCA-2 significantly (p<0.05) inhibited TLR9- but not TLR7-induced IFN-α production by PDCs from both clinical groups. These findings suggest that differences exist in TLR7- and TLR9-induced IFN-α production by PDCs in HIV-infected individuals that are not directly related to BDCA-2 down-modulation.
doi:10.1089/aid.2012.0200
PMCID: PMC3581027  PMID: 23131038
16.  Genetic Characterization and Transmitted Drug Resistance of the HIV Type 1 Epidemic in Men Who Have Sex with Men in Beijing, China 
Abstract
A rapid increase in the number of HIV cases in the men who have sex with men (MSM) population has been observed in China; however, little information is available on the genetic characterization of HIV prevalent in this population. In this study, 95 HIV-1-seropositive drug-naive patients from the Beijing MSM population were enrolled. The genetic characterization and transmission of drug resistance of HIV-1 were examined based on full-length gag, pol, and partial env gene sequences. Three subtypes, including CRF01_AE (56.0%), B (30.8%), and CRF07_BC (12.6%), were identified. Close phylogenetic relationships were found among these strains with isolates from other populations in Beijing and MSM isolates from Hebei province, which suggested that the Beijing MSM population might act as a bridge for HIV transmission between MSM and other high-risk populations. Drug-resistant mutations were identified in 5.3% of sampled individuals. Our results provided detailed genetic data and would be helpful for understanding the transmitting pattern of HIV strains between MSM and other populations.
doi:10.1089/aid.2012.0281
PMCID: PMC3581030  PMID: 23121221
17.  Immunologic Risk Factors for Early Mortality After Starting Antiretroviral Therapy in HIV-Infected Zambian Children 
Abstract
To explore immunologic risk factors for death within 90 days of highly active antiretroviral therapy (HAART) initiation, CD4+ and CD8+ T cell subsets were measured by flow cytometry and characterized by logistic regression in 149 Zambian children between 9 months and 10 years of age enrolled in a prospective, observational study of the impact of HAART on measles immunity. Of 21 children who died during follow-up, 17 (81%) had known dates of death and 16 (76%) died within 90 days of initiating HAART. Young age and low weight-for-age z-scores were associated with increased risks of mortality within 90 days of starting HAART, whereas CD4+ T cell percentage was not associated with mortality. After adjusting for these factors, each 10% increase in CD8+ effector T cells increased the odds of overall mortality [OR=1.43 (95% CI: 1.08, 1.90)] and was marginally associated with early mortality [OR=1.29 (95% CI: 0.97, 1.72)]. Conversely, each 10% increase in CD4+ central memory T cells decreased the odds of overall [OR=0.06 (95% CI: 0.01, 0.59)] and early mortality [OR=0.09 (95% CI: 0.01, 0.97)]. Logistic regression prediction models demonstrated areas under the receiver-operator characteristic curves of ≥85% for early and overall mortality, with bootstrapped sensitivities of 82–85% upon validation, supporting the predictive accuracy of the models. CD4+ and CD8+ T cell subsets may be more accurate predictors of early mortality than CD4+ T cell percentages and could be used to identify children who would benefit from more frequent clinical monitoring after initiating HAART.
doi:10.1089/aid.2012.0246
PMCID: PMC3581031  PMID: 23025633
18.  Short Communication: Fasting Increases Serum Concentrations of Bilirubin in Patients Receiving Atazanavir: Results from a Pilot Study 
Abstract
Unconjugated hyperbilirubinemia resulting from therapy with atazanavir is physiologically related to hyperbilirubinemia in Gilbert's syndrome (GS). In patients with GS, changes in diet have a significant impact on bilirubinemia. Our aim was to investigate whether changes in diet affect the level of serum bilirubin in patients receiving atazanavir. Thirty patients on stable therapy with ritonavir-boosted atazanavir without evidence of GS were enrolled. Hemolysis and chronic hepatitis were excluded. After a baseline period of normal intake of calories, the patients were randomized to follow a 24-h 400-calorie diet (fasting), then a 48-h period of normal calorie intake and, afterward, a 24-h period of a high-calorie diet, or the same interventions in inverse order. Serum bilirubin concentrations were measured before and after each intervention. A high adherence to the recommended diet was observed. The mean unconjugated bilirubin concentration before the high-calorie diet was 2.79±1.53 mg/dl and after such intervention it was 2.70±1.40 mg/dl. The mean difference between preintervention and postintervention was −0.08±0.69 mg/dl (p=NS). The mean unconjugated bilirubin concentration before the fasting diet was 2.31±1.23 mg/dl and it was 3.84±1.90 mg/dl after. The mean difference between prefasting and postfasting was 1.53±1.17 mg/dl (p=0.001). According to these results, short periods of fasting seem to increase the unconjugated bilirubin concentration in patients on atazanavir. A high-calorie diet did not have any impact in bilirubin probably because most patients follow similar diets in their everyday life.
doi:10.1089/aid.2012.0232
PMCID: PMC3581034  PMID: 23113663
19.  Outcomes of Second Combination Antiretroviral Therapy Regimens Among HIV-Infected Persons in Clinical Care: A Multicenter Cohort Study 
Abstract
Data on the effectiveness of second-line combination antiretroviral therapy (cART) are limited. We evaluated virologic outcomes of second cART in a multicenter cohort collaboration. The study population initiated first and second modern cART between 1996 and 2010. The second cART required a switch in at least the anchor agent of first cART. We evaluated time to virologic failure of second cART and factors associated with greater risk of failure using multivariable Cox proportional hazards models. Of 488 patients who switched to second-line cART, 67% were black and 32% were women. The median HIV-1 RNA at second cART initiation was 9,565 copies/ml [interquartile range (IQR); 123, 94,108]. The time to virologic failure of second cART was longer if HIV-1 RNA was undetectable at switch (p=0.001), although 12% and 17% of patients with undetectable and detectable HIV-1 RNA experienced virologic failure within 6 months of second cART initiation, respectively. A lower CD4 cell count at second cART initiation was associated with a greater risk of virologic failure. Failure rates decreased in more recent calendar years [adjusted relative hazard of 0.40 comparing 2008 to 2010 with 1996 to 1998 (95% confidence interval; 0.15, 1.00)]; however, type of anchor agent was not associated with failure. In conclusion, virologic failure of second cART was less likely if patients switched with undetectable HIV-1 RNA, although risk of early failure was similar. The effectiveness of second cART regimens improved over calendar time and was independent of the anchor agent in the regimen.
doi:10.1089/aid.2012.0210
PMCID: PMC3581035  PMID: 23072322
20.  Short Communication: From Wasting to Obesity: Initial Antiretroviral Therapy and Weight Gain in HIV-Infected Persons 
Abstract
Data on weight gain and the progression to overweight/obesity in HIV-infected persons during initial combination antiretroviral therapy (cART) are limited, and comparisons to the general population are inconclusive. Weight and body mass index (BMI) changes were studied in HIV-infected adults who remained on initial cART for 12 consecutive months and in an HIV-uninfected cohort receiving care at Duke University Medical Center between 1998 and 2008. Overweight/obesity was defined as BMI ≥25 kg/m2. Variables were analyzed by Chi-square and Student's t-tests. Ninety-two HIV-infected persons (median age 38.2 years) met inclusion criteria. Weight and BMI increased during 12 months of cART (80.0 to 84.4 kg, p<0.0001; 26.4 to 27.9 kg/m2, p<0.0001; respectively). Weight gain was greater in HIV-infected females compared to males (8.6 vs. 3.6 kg, p=0.04), in persons treated with protease inhibitor (PI)-based cART compared to non-PI-based cART (9.0 vs. 2.7 kg, p=0.001), and in persons with a pretreatment CD4 count <200 cells/mm3 compared to ≥200 cells/mm3 (8.9 vs. 0.3 kg, p<0.0001). Overweight/obesity prevalence increased from 52% to 66% during 12 months of initial cART, a 27% relative increase (p=0.002). HIV-infected persons had a lower prevalence of pretreatment overweight/obesity compared to 94 age-matched control subjects (52% vs. 91%, p<0.001); however, there was no change in weight (92.7 vs. 93.0 kg, p=0.5) or overweight/obesity prevalence (91% to 92%, p>0.9) during 12 months in the control cohort. Management should anticipate excess weight gain during the first year of cART in persons who are female, have a pretreatment CD4 <200 cells/mm3, or will initiate PI-based cART.
doi:10.1089/aid.2012.0234
PMCID: PMC3581041  PMID: 23072344
21.  Performance of Immunological Response in Predicting Virological Failure 
Abstract
In HIV-infected individuals on antiretroviral therapy (ART), the decision on when to switch from first-line to second-line therapy is dictated by treatment failure, and this can be measured in three ways: clinically, immunologically, and virologically. While viral load (VL) decreases and CD4 cell increases typically occur together after starting ART, discordant responses may be seen. Hence the current study was designed to determine the immunological and virological response to ART and to evaluate the utility of immunological response to predict virological failure. All treatment-naive HIV-positive individuals aged >18 years who were eligible for ART were enrolled and assessed at baseline, 6 months, and 12 months clinically and by CD4 cell count and viral load estimations. The patients were categorized as showing concordant favorable (CF), immunological only (IO), virological only (VO), and concordant unfavorable responses (CU). The efficiency of immunological failure to predict virological failure was analyzed across various levels of virological failure (VL>50, >500, and >5,000 copies/ml). At 6 months, 87(79.81%), 7(5.5%), 13 (11.92%), and 2 (1.83%) patients and at 12 months 61(69.3%), 9(10.2%), 16 (18.2%), and 2 (2.3%) patients had CF, IO, VO, and CU responses, respectively. Immunological failure criteria had a very low sensitivity (11.1–40%) and positive predictive value (8.3–25%) to predict virological failure. Immunological criteria do not accurately predict virological failure resulting in significant misclassification of therapeutic responses. There is an urgent need for inclusion of viral load testing in the initiation and monitoring of ART.
doi:10.1089/aid.2012.0266
PMCID: PMC3581063  PMID: 23137294
22.  Assessment of Biomarkers of Cardiovascular Risk Among HIV Type 1-Infected Adolescents: Role of Soluble Vascular Cell Adhesion Molecule As an Early Indicator of Endothelial Inflammation 
Abstract
Cardiovascular disease (CVD) biomarkers were examined in a cohort of HIV-infected and HIV-uninfected adolescents who participated in Adolescent Trials Network study 083 utilizing samples from the Reaching for Excellence in Adolescent Care cohort, a longitudinal study of youth infected through adult risk behavior. Nonfasting blood samples from 97 HIV-infected and 81 HIV-uninfected adolescents infected by adult risk behaviors were analyzed for total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), very low-density lipoprotein (VLDL), triglycerides, apolipoprotein A-I, high-sensitivity C-reactive protein (hsCRP), soluble vascular adhesion molecule-1 (sVCAM-1), myeloperoxidase, and neopterin at baseline and 18 months later. Results were analyzed using ANOVA, Wilcoxon signed-rank, and paired t tests. Among infected subjects 67 received antiretroviral therapy and 30 were treatment naive. The HIV-infected and HIV-uninfected subjects were similar in gender, ethnicity, and cardiovascular risk factors such as smoking and obesity. In all groups lipid parameters were within accepted guidelines for cardiovascular risk. Among HIV-infected youth on antiretroviral therapy (ART), HDL and apoprotein A-I were significantly lower when compared to uninfected youth. hsCRP was not elevated and thus not predictive for risk in any group. sVCAM-1 levels were significantly elevated in both HIV-infected groups: 1,435 ng/ml and 1,492 ng/ml in untreated and treated subjects, respectively, and 1,064 ng/ml in the uninfected group (p<0.0001). Across all groups neopterin correlated with sVCAM at 18 months (Spearman correlation coefficient 0.58, p<0.0001). Only 9% of ART-treated subjects fully suppressed virus. Lipid profiles and hsCRP, traditional markers of cardiovascular disease, are not abnormal among HIV-infected youth but elevated sVCAM may be an early marker of atherosclerosis.
doi:10.1089/aid.2012.0086
PMCID: PMC3581064  PMID: 23062187
23.  Targeting of Conserved Gag-Epitopes in Early HIV Infection Is Associated with Lower Plasma Viral Load and Slower CD4+ T Cell Depletion 
Abstract
We aimed to investigate whether the character of the immunodominant HIV-Gag peptide (variable or conserved) targeted by CD8+ T cells in early HIV infection would influence the quality and quantity of T cell responses, and whether this would affect the rate of disease progression. Treatment-naive HIV-infected study subjects within the OPTIONS cohort at the University of California, San Francisco, were monitored from an estimated 44 days postinfection for up to 6 years. CD8+ T cells responses targeting HLA-matched HIV-Gag-epitopes were identified and characterized by multicolor flow cytometry. The autologous HIV gag sequences were obtained. We demonstrate that patients targeting a conserved HIV-Gag-epitope in early infection maintained their epitope-specific CD8+ T cell response throughout the study period. Patients targeting a variable epitope showed decreased immune responses over time, although there was no limitation of the functional profile, and they were likely to target additional variable epitopes. Maintained immune responses to conserved epitopes were associated with no or limited sequence evolution within the targeted epitope. Patients with immune responses targeting conserved epitopes had a significantly lower median viral load over time compared to patients with responses targeting a variable epitope (0.63 log10 difference). Furthermore, the rate of CD4+ T cell decline was slower for subjects targeting a conserved epitope (0.85% per month) compared to subjects targeting a variable epitope (1.85% per month). Previous studies have shown that targeting of antigens based on specific HLA types is associated with a better disease course. In this study we show that categorizing epitopes based on their variability is associated with clinical outcome.
doi:10.1089/aid.2012.0171
PMCID: PMC3581067  PMID: 23140171
24.  Serum 25-Hydroxyvitamin D Levels and C-Reactive Protein in Persons with Human Immunodeficiency Virus Infection 
Abstract
Human immunodeficiency virus (HIV) infection has frequently been associated with vitamin D deficiency as well as chronic inflammatory response. We tested the hypothesis of an independent relationship between serum concentrations of 25-hydroxyvitamin D [25(OH)D] and high-sensitivity C-reactive protein (CRP) in a cohort of HIV-positive people. A cross-sectional survey was conducted among 316 HIV-positive people (181 men and 135 women) aged 16 to 60 years residing in the Kathmandu Valley, Nepal. Serum high-sensitivity CRP concentrations and serum 25(OH)D levels were measured by the latex agglutination nephelometry method and the competitive protein-binding assay, respectively. The relationship between serum CRP concentrations and 25(OH)D serum level was assessed using multiple logistic regression analysis with adjustment of potential cardiovascular and HIV-related factors. The proportions of participants with 25(OH)D serum levels <20 ng/ml, 20–30 ng/ml, and ≥30 ng/ml were 83.2%, 15.5%, and 1.3%, respectively. The mean 25(OH)D serum levels in men and women were 15.3 ng/ml and 14.4 ng/ml, respectively. Participants with a 25(OH)D serum level of <20 ng/ml had a 3.2-fold higher odds of high CRP (>3 mg/liter) compared to those with a 25(OH)D serum level of ≥20 ng/ml (p=0.005). Men and women with a 25(OH)D serum level of <20 ng/ml had 3.2- and 2.7-fold higher odds of high CRP (>3 mg/liter), respectively, compared to those with a 25(OH)D serum level of ≥20 ng/ml. The relationships remained significant only in men (p =0.02) but not in women (p=0.28). The risk of having a high level of inflammation (CRP>3 mg/liter) may be high among HIV-positive men and women with a 25(OH)D serum level of <20 ng/ml.
doi:10.1089/aid.2012.0120
PMCID: PMC3581068  PMID: 23003113
25.  Short Communication: HIV Type 1 Subtype C Variants Transmitted Through the Bottleneck of Breastfeeding Are Sensitive to New Generation Broadly Neutralizing Antibodies Directed Against Quaternary and CD4-Binding Site Epitopes 
Abstract
Mother-to-child transmission of HIV-1 subtype C can occur in utero, intrapartum, or via breast milk exposure. While not well understood, there are putative differences in the mechanisms involved with the distinct routes of vertical HIV transmission. Here, we address the question of whether specific viral characteristics are common to variants transmitted through breastfeeding that may facilitate evasion of innate or adaptive immune responses. We amplified the envelope gene (env) from the plasma of six infants during acute infection who were infected with HIV-1 subtype C through breastfeeding, and from three available matched maternal samples. We sequenced the full-length env genes in these subjects revealing heterogeneous viral populations in the mothers and homogeneous populations in the infants. In five infants, the viral population arose from a single variant, while two variants were detected in the remaining infant. Infant env sequences had fewer N-linked glycosylation sites and shorter sequences than those of the available matched maternal samples. Though the small size of the study precluded our ability to test statistical significance, these results are consistent with selection for virus with shorter variable loops and fewer glycosylation sites during transmission of HIV-1 subtype C in other settings. Transmitted envs were resistant to neutralization by antibodies 2G12 and 2F5, but were generally sensitive to the more broadly neutralizing PG9, PG16, and VRC01, indicating that this new generation of broadly neutralizing monoclonal antibodies could be efficacious in passive immunization strategies.
doi:10.1089/aid.2012.0197
PMCID: PMC3581069  PMID: 23075434

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