OBJECTIVE:Recent surveillance data suggests the United States (U.S.) Army HIV epidemic is concentrated among men who have sex with men. To identify potential targets for HIV prevention strategies, the relationship between demographic and clinical factors and membership within transmission clusters based on baseline pol sequences of HIV-infected Soldiers from 2001 through 2012 were analyzed. METHODS:We conducted a retrospective analysis of baseline partial pol sequences, demographic and clinical characteristics available for all Soldiers in active service and newly-diagnosed with HIV-1 infection from January 1, 2001 through December 31, 2012. HIV-1 subtype designations and transmission clusters were identified from phylogenetic analysis of sequences. Univariate and multivariate logistic regression models were used to evaluate and adjust for the association between characteristics and cluster membership. RESULTS:Among 518 of 995 HIV-infected Soldiers with available partial pol sequences, 29% were members of a transmission cluster. Assignment to a southern U.S. region at diagnosis and year of diagnosis were independently associated with cluster membership after adjustment for other significant characteristics (p<0.10) of age, race, year of diagnosis, region of duty assignment, sexually transmitted infections, last negative HIV test, antiretroviral therapy, and transmitted drug resistance. Subtyping of the pol fragment indicated HIV-1 subtype B infection predominated (94%) among HIV-infected Soldiers. CONCLUSION:These findings identify areas to explore as HIV prevention targets in the U.S. Army. An increased frequency of current force testing may be justified, especially among Soldiers assigned to duty in installations with high local HIV prevalence such as southern U.S. states.

ABSTRACT Eliciting broadly reactive functional antibodies remains a challenge in human immunodeficiency virus type 1 (HIV-1) vaccine development that is complicated by variations in envelope (Env) subtype and structure. The majority of new global HIV-1 infections are subtype C, and novel antigenic properties have been described for subtype C Env proteins. Thus, an HIV-1 subtype C Env protein (CO6980v0c22) from an infected person in the acute phase (Fiebig stage I/II) was developed as a research reagent and candidate immunogen. The gp145 envelope is a novel immunogen with a fully intact membrane-proximal external region (MPER), extended by a polylysine tail. Soluble gp145 was enriched for trimers that yielded the expected “fan blade” motifs when visualized by cryoelectron microscopy. CO6980v0c22 gp145 reacts with the 4E10, PG9, PG16, and VRC01 HIV-1 neutralizing monoclonal antibodies (MAbs), as well as the V1/V2-specific PGT121, 697, 2158, and 2297 MAbs. Different gp145 oligomers were tested for immunogenicity in rabbits, and purified dimers, trimers, and larger multimers elicited similar levels of cross-subtype binding and neutralizing antibodies to tier 1 and some tier 2 viruses. Immunized rabbit sera did not neutralize the highly resistant CO6980v0c22 pseudovirus but did inhibit the homologous infectious molecular clone in a peripheral blood mononuclear cell (PBMC) assay. This Env is currently in good manufacturing practice (GMP) production to be made available for use as a clinical research tool and further evaluation as a candidate vaccine. IMPORTANCE At present, the product pipeline for HIV vaccines is insufficient and is limited by inadequate capacity to produce large quantities of vaccine to standards required for human clinical trials. Such products are required to evaluate critical questions of vaccine formulation, route, dosing, and schedule, as well as to establish vaccine efficacy. The gp145 Env protein presented in this study forms physical trimers, binds to many of the well-characterized broad neutralizing MAbs that target conserved Env epitopes, and induce cross-subtype neutralizing antibodies as measured in both cell line and primary cell assays. This subtype C Env gp145 protein is currently undergoing good manufacturing practice production for use as a reagent for preclinical studies and for human clinical research. This product will serve as a reagent for comparative studies and may represent a next-generation candidate HIV immunogen.

The RV144 Thai vaccine trial has been the only vaccine study to show efficacy in preventing HIV infection. Ongoing molecular surveillance of HIV-1 in Southeast Asia is vital for vaccine development and evaluation. In this study a novel tool, the multi-region subtype specific PCR (MSSP) assay, that was able to identify subtypes B, C, CRF01_AE for Thailand, other Southeast Asian countries, India and China is described. The MSSP assay is based on a nested PCR strategy and amplifies eight short regions distributed along the HIV-1 genome using subtype-specific primers. A panel of 41 clinical DNA samples obtained primarily from opiate users in northern Thailand was used to test the assay performance. The MSSP assay provided 73-100% sensitivity and 100% specificity for the three subtypes in each genome region. The assay was then field-tested on 337 sera from HIV infected northern Thai drug users collected between 1999 and 2002. Subtype distribution was CRF01_AE 77.4% (n=261), subtype B 33% (n =11), CRFOLAE/B recombinant 12.2% (n= 41), CRF01_AE/C recombinant 0.6% (n = 2), and non-typeable 6.5% (n =22). The MSSP assay is a simple, cost-effective, and accurate genotyping tool for laboratory settings with limited resources and is sensitive enough to capture the recombinant genomes and dual infections. (C) 2015 Elsevier B.V. All rights reserved.

Characterization of HIV-1 subtype diversity in regions where vaccine trials are conducted is critical for vaccine development and testing. This study describes the molecular epidemiology of HIV-1 within a tea-plantation community cohort in Kericho, Kenya. Sixty-three incident infections were ascertained in the HIV and Malaria Cohort Study conducted in Kericho from 2003 to 2006. HIV-1 strains from 58 of those individuals were full genome characterized and compared to two previous Kenyan studies describing 41 prevalent infections from a blood bank survey (1999-2000) and 21 infections from a higher-risk cohort containing a mix of incident and prevalent infections (2006). Among the 58 strains from the community cohort, 43.1% were pure subtypes (36.2% A1, 5.2% C, and 1.7% G) and 56.9% were inter-subtype recombinants (29.3% A1D, 8.6% A1CD, 6.9% A1A2D, 5.2% A1C, 3.4% A1A2CD, and 3.4% A2D). This diversity and the resulting genetic distance between the observed strains will need to be addressed when vaccine immunogens are chosen. In consideration of current vaccine development efforts, the strains from these three studies were compared to five candidate vaccines (each of which are viral vectored, carrying inserts corresponding to parts of gag, pol, and envelope), which have been developed for possible use in sub-Saharan Africa. The sequence comparison between the observed strains and the candidate vaccines indicates that in the presence of diverse recombinants, a bivalent vaccine is more likely to provide T-cell epitope coverage than monovalent vaccines even when the inserts of the bivalent vaccine are not subtype-matched to the local epidemic.

AIDS Research and Human RetrovirusesVol. 30, No. S1 Viral Transmission StudiesFree AccessCryptic Multiple HIV-1 Infection Revealed by Early, Frequent, and Deep Sampling during Acute InfectionGustavo Hernan Kijak, Eric Sanders-Buell, Agnes-Laurance Chenine, Michael Eller, Nilu Goonetilleke, Rasmi Thomas, Sivan Leviyang, Elizabeth Harbolick, Meera Bose, Phuc Pham, Celina Oropeza, Kultida Poltavee, Anne Marie O'Sullivan, Melanie Merbah, Margaret Costanzo, Hui Li, Will Fischer, Feng Gao, Leigh Anne Eller, Robert J. O'Connell, Samuel Sinei, Lucas Maganga, Hannah Kibuuka, Sorachai Nitayaphan, Morgane Rolland, Bette Korber, Francine McCutchan, George Shaw, Nelson Michael, Merlin Robb, Sodsai Tovanabutra, and Jerome KimGustavo Hernan KijakU.S. Military HIV Research Program (MHRP), Walter Reed Army Institute of Research, Silver Spring, MD, United StatesU.S. Military HIV Research Program (MHRP)/ Henry M. Jackson Foundation, Silver Spring, MD, United StatesSearch for more papers by this author, Eric Sanders-BuellU.S. Military HIV Research Program (MHRP), Walter Reed Army Institute of Research, Silver Spring, MD, United StatesU.S. Military HIV Research Program (MHRP)/ Henry M. Jackson Foundation, Silver Spring, MD, United StatesSearch for more papers by this author, Agnes-Laurance ChenineU.S. Military HIV Research Program (MHRP), Walter Reed Army Institute of Research, Silver Spring, MD, United StatesU.S. Military HIV Research Program (MHRP)/ Henry M. Jackson Foundation, Silver Spring, MD, United StatesSearch for more papers by this author, Michael EllerU.S. Military HIV Research Program (MHRP), Walter Reed Army Institute of Research, Silver Spring, MD, United StatesU.S. Military HIV Research Program (MHRP)/ Henry M. Jackson Foundation, Silver Spring, MD, United StatesSearch for more papers by this author, Nilu GoonetillekeSchool of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, NC, United StatesSearch for more papers by this author, Rasmi ThomasU.S. Military HIV Research Program (MHRP), Walter Reed Army Institute of Research, Silver Spring, MD, United StatesU.S. Military HIV Research Program (MHRP)/ Henry M. Jackson Foundation, Silver Spring, MD, United StatesSearch for more papers by this author, Sivan LeviyangDepartment of Mathematics and Statistics, Georgetown University, Washington, DC, United StatesSearch for more papers by this author, Elizabeth HarbolickU.S. Military HIV Research Program (MHRP), Walter Reed Army Institute of Research, Silver Spring, MD, United StatesU.S. Military HIV Research Program (MHRP)/ Henry M. Jackson Foundation, Silver Spring, MD, United StatesSearch for more papers by this author, Meera BoseU.S. Military HIV Research Program (MHRP), Walter Reed Army Institute of Research, Silver Spring, MD, United StatesU.S. Military HIV Research Program (MHRP)/ Henry M. Jackson Foundation, Silver Spring, MD, United StatesSearch for more papers by this author, Phuc PhamU.S. Military HIV Research Program (MHRP), Walter Reed Army Institute of Research, Silver Spring, MD, United StatesU.S. Military HIV Research Program (MHRP)/ Henry M. Jackson Foundation, Silver Spring, MD, United StatesSearch for more papers by this author, Celina OropezaU.S. Military HIV Research Program (MHRP), Walter Reed Army Institute of Research, Silver Spring, MD, United StatesU.S. Military HIV Research Program (MHRP)/ Henry M. Jackson Foundation, Silver Spring, MD, United StatesSearch for more papers by this author, Kultida PoltaveeU.S. Military HIV Research Program (MHRP), Walter Reed Army Institute of Research, Silver Spring, MD, United StatesU.S. Military HIV Research Program (MHRP)/ Henry M. Jackson Foundation, Silver Spring, MD, United StatesSearch for more papers by this author, Anne Marie O'SullivanU.S. Military HIV Research Program (MHRP), Walter Reed Army Institute of Research, Silver Spring, MD, United StatesU.S. Military HIV Research Program (MHRP)/ Henry M. Jackson Foundation, Silver Spring, MD, United StatesSearch for more papers by this author, Melanie MerbahU.S. Military HIV Research Program (MHRP), Walter Reed Army Institute of Research, Silver Spring, MD, United StatesU.S. Military HIV Research Program (MHRP)/ Henry M. Jackson Foundation, Silver Spring, MD, United StatesSearch for more papers by this author, Margaret CostanzoU.S. Military HIV Research Program (MHRP), Walter Reed Army Institute of Research, Silver Spring, MD, United StatesU.S. Military HIV Research Program (MHRP)/ Henry M. Jackson Foundation, Silver Spring, MD, United StatesSearch for more papers by this author, Hui LiPerelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United StatesSearch for more papers by this author, Will FischerTheoretical Biology, Los Alamos National Laboratory, Los Alamos, NM, United StatesSearch for more papers by this author, Feng GaoDuke Human Vaccine Institute, Duke University Medical Center, Durham, NC, United StatesSearch for more papers by this author, Leigh Anne EllerU.S. Military HIV Research Program (MHRP), Walter Reed Army Institute of Research, Silver Spring, MD, United StatesU.S. Military HIV Research Program (MHRP)/ Henry M. Jackson Foundation, Silver Spring, MD, United StatesSearch for more papers by this author, Robert J. O'ConnellArmed Forces Research Institute of Medical Sciences, Bangkok, ThailandSearch for more papers by this author, Samuel SineiWalter Reed Project, Kericho, KenyaSearch for more papers by this author, Lucas MagangaMbeya Medical Research Programme, Mbeya, Tanzania, United Republic ofSearch for more papers by this author, Hannah KibuukaMakerere University-Walter Reed Project, Kampala, UgandaSearch for more papers by this author, Sorachai NitayaphanArmed Forces Research Institute of Medical Sciences, Bangkok, ThailandSearch for more papers by this author, Morgane RollandU.S. Military HIV Research Program (MHRP), Walter Reed Army Institute of Research, Silver Spring, MD, United StatesU.S. Military HIV Research Program (MHRP)/ Henry M. Jackson Foundation, Silver Spring, MD, United StatesSearch for more papers by this author, Bette KorberTheoretical Biology, Los Alamos National Laboratory, Los Alamos, NM, United StatesSearch for more papers by this author, Francine McCutchanIndependent Consultant, Silver Spring, MD, United StatesSearch for more papers by this author, George ShawPerelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United StatesSearch for more papers by this author, Nelson MichaelU.S. Military HIV Research Program (MHRP), Walter Reed Army Institute of Research, Silver Spring, MD, United StatesSearch for more papers by this author, Merlin RobbU.S. Military HIV Research Program (MHRP), Walter Reed Army Institute of Research, Silver Spring, MD, United StatesU.S. Military HIV Research Program (MHRP)/ Henry M. Jackson Foundation, Silver Spring, MD, United StatesSearch for more papers by this author, Sodsai TovanabutraU.S. Military HIV Research Program (MHRP), Walter Reed Army Institute of Research, Silver Spring, MD, United StatesU.S. Military HIV Research Program (MHRP)/ Henry M. Jackson Foundation, Silver Spring, MD, United StatesSearch for more papers by this author, and Jerome KimU.S. Military HIV Research Program (MHRP), Walter Reed Army Institute of Research, Silver Spring, MD, United StatesSearch for more papers by this authorPublished Online:30 Oct 2014https://doi.org/10.1089/aid.2014.5102a.abstractAboutSectionsPDF/EPUB Permissions & CitationsPermissionsDownload CitationsTrack CitationsAdd to favorites Back To Publication ShareShare onFacebookXLinked InRedditEmail OA21.06 LBBackground: In acute HIV-1 infection (AHI) single genome sequencing (SGS) revealed a strong bottleneck at transmission, with 60–90% of sexual infections being established by a single transmitted/founder (T/F) virus. We combined early and frequent sampling with targeted deep sequencing (TDS) to study viral evolution during AHI.Methods: We studied 7 HIV(-) at entry high-risk RV217 volunteers (2 M and 5 F, all with sexual risk) with documented HIV nucleic acid (NA) conversion after twice-weekly testing. Starting at d2-7 (d0: first NA+ date), we studied 8–9 consecutive plasma samples (mean sampling interval: 4.1d; peak viremia: d10-18; 1–5 samples were from pre-peak viremia) by HIV SGS and TDS (Ion Torrent; limit of detection: 0.5%).Results: 6/7 persons had pre-peak viremia SGS profiles consistent with infection by a single T/F virus. However, in 4 persons, additional variants were detected by TDS: in 3 persons at d2-7 (frequency: 0.5–4.3%), and in one at d21. Viral populations evolved at dramatic rates, but with different patterns. In #1, the minor variant circulated at <5% until d17, then increased to 57% by d31. In #2, the minor variant increased from 3.5% (d7) to 93% (d21), and then decreased to <0.5% by d42. In #3 the minor variant was at 0.5–1% between d7-16, then became undetectable, but was 53% at d181. In participant #4, 2 minor variants were detected at d21 (0.5–1.4%), increasing by d28 to 16–36%, respectively. Full length genetic distances between cognate major and minor variants were 1.0–2.2%, consistent with acquisition of multiple viruses from the same donor. Inter-variant recombinants were detected from d21 onward. During early AHI, both major and minor variants acquired CTL-escape mutations.Conclusions: We show that in apparent single infections minor variants can occur at levels not detectable by SGS (i.e., cryptic multiple infection). Furthermore these variants contribute to viral evolution, which may have profound implications for HIV pathogenesis, cure, treatment, and vaccine design.FiguresReferencesRelatedDetailsCited byLessons from acute HIV infectionCurrent Opinion in HIV and AIDS, Vol. 11, No. 6Bottlenecks in HIV-1 transmission: insights from the study of founder viruses8 June 2015 | Nature Reviews Microbiology, Vol. 13, No. 7 Volume 30Issue S1Oct 2014 InformationCopyright 2014, Mary Ann Liebert, Inc.To cite this article:Gustavo Hernan Kijak, Eric Sanders-Buell, Agnes-Laurance Chenine, Michael Eller, Nilu Goonetilleke, Rasmi Thomas, Sivan Leviyang, Elizabeth Harbolick, Meera Bose, Phuc Pham, Celina Oropeza, Kultida Poltavee, Anne Marie O'Sullivan, Melanie Merbah, Margaret Costanzo, Hui Li, Will Fischer, Feng Gao, Leigh Anne Eller, Robert J. O'Connell, Samuel Sinei, Lucas Maganga, Hannah Kibuuka, Sorachai Nitayaphan, Morgane Rolland, Bette Korber, Francine McCutchan, George Shaw, Nelson Michael, Merlin Robb, Sodsai Tovanabutra, and Jerome Kim.Cryptic Multiple HIV-1 Infection Revealed by Early, Frequent, and Deep Sampling during Acute Infection.AIDS Research and Human Retroviruses.Oct 2014.A58-A58.http://doi.org/10.1089/aid.2014.5102a.abstractPublished in Volume: 30 Issue S1: October 30, 2014PDF download

ABSTRACT Neutralizing antibodies (nAbs) are a high priority for vaccines that aim to prevent the acquisition of HIV-1 infection. Vaccine effectiveness will depend on the extent to which induced antibodies neutralize the global diversity of circulating HIV-1 variants. Using large panels of genetically and geographically diverse HIV-1 Env-pseudotyped viruses and chronic infection plasma samples, we unambiguously show that cross-clade nAb responses are commonly induced in response to infection by any virus clade. Nonetheless, neutralization was significantly greater when the plasma clade matched the clade of the virus being tested. This within-clade advantage was diminished in older, more-diverse epidemics in southern Africa, the United States, and Europe compared to more recent epidemics in Asia. It was most pronounced for circulating recombinant form (CRF) 07_BC, which is common in China and is the least-divergent lineage studied; this was followed by the slightly more diverse Asian CRF01_AE. We found no evidence that transmitted/founder viruses are generally more susceptible to neutralization and are therefore easier targets for vaccination than chronic viruses. Features of the gp120 V1V2 loop, in particular, length, net charge, and number of N-linked glycans, were associated with Env susceptibility and plasma neutralization potency in a manner consistent with neutralization escape being a force that drives viral diversification and plasma neutralization breadth. The overall susceptibility of Envs and potencies of plasma samples were highly predictive of the neutralization outcome of any single virus-plasma combination. These findings highlight important considerations for the design and testing of candidate HIV-1 vaccines that aim to elicit effective nAbs. IMPORTANCE An effective HIV-1 vaccine will need to overcome the extraordinary variability of the virus, which is most pronounced in the envelope glycoproteins (Env), which are the sole targets for neutralizing antibodies (nAbs). Distinct genetic lineages, or clades, of HIV-1 occur in different locales that may require special consideration when designing and testing vaccines candidates. We show that nAb responses to HIV-1 infection are generally active across clades but are most potent within clades. Because effective vaccine-induced nAbs are likely to share these properties, optimal coverage of a particular clade or combination of clades may require clade-matched immunogens. Optimal within-clade coverage might be easier to achieve in regions such as China and Thailand, where the epidemic is more recent and the virus less diverse than in southern Africa, the United States, and Europe. Finally, features of the first and second hypervariable regions of gp120 (V1V2) may be critical for optimal vaccine design.

Standardized assays to assess vaccine and antiviral drug efficacy are critical for the development of protective HIV-1 vaccines and drugs. These immune assays will be advanced by the development of standardized viral stocks, such as HIV-1 infectious molecular clones (IMC), that i) express a reporter gene, ii) are representative of globally diverse subtypes and iii) are engineered to easily exchange envelope (env) genes for expression of sequences of interest. Thus far, a subtype B IMC backbone expressing Renilla luciferase (LucR), and into which the ectodomain of heterologous env coding sequences can be expressed has been successfully developed but as execution of HIV-1 vaccine efficacy trials shifts increasingly to non-subtype B epidemics (Southern African and Southeast Asia), non-subtype B HIV-1 reagents are needed to support vaccine development. Here we describe two IMCs derived from subtypes C and CRF01_AE HIV-1 primary isolates expressing LucR (IMC. LucR) that were engineered to express heterologous gp160 Envs. 18 constructs expressing various subtypes C and CRF01_AE Envs, mostly acute, in subtype-matched and -unmatched HIV backbones were tested for functionality and neutralization sensitivity. Our results suggest a possible effect of non-env HIV-1 genes on the interaction of Env and neutralizing antibodies and highlight the need to generate a library of IMCs representative of the HIV-1 subtype spectrum to be used as standardized neutralization assay reagents for assessing HIV-1 vaccine efficacy.

The RV144 HIV-1 vaccine trial (Thailand, 2003 to 2009), using immunogens genetically matched to the regional epidemic, demonstrated the first evidence of efficacy for an HIV-1 vaccine. Here we studied the molecular evolution of the HIV-1 epidemic from the time of immunogen selection to the execution of the efficacy trial. We studied HIV-1 genetic diversity among 390 volunteers who were deferred from enrollment in RV144 due to preexisting HIV-1 infection using a multiregion hybridization assay, full-genome sequencing, and phylogenetic analyses. The subtype distribution was 91.7% CRF01_AE, 3.5% subtype B, 4.3% B/CRF01_AE recombinants, and 0.5% dual infections. CRF01_AE strains were 31% more diverse than the ones from the 1990s Thai epidemic. Sixty-nine percent of subtype B strains clustered with the cosmopolitan Western B strains. Ninety-three percent of B/CRF01_AE recombinants were unique; recombination breakpoint analysis showed that these strains were highly embedded within the larger network that integrates recombinants from East/Southeast Asia. Compared to Thai sequences from the early 1990s, the distance to the RV144 immunogens increased 52% to 68% for CRF01_AE Env immunogens and 12% to 29% for subtype B immunogens. Forty-three percent to 48% of CRF01_AE sequences differed from the sequence of the vaccine insert in Env variable region 2 positions 169 and 181, which were implicated in vaccine sieve effects in RV144. In conclusion, compared to the molecular picture at the early stages of vaccine development, our results show an overall increase in the genetic complexity of viruses in the Thai epidemic and in the distance to vaccine immunogens, which should be considered at the time of the analysis of the trial results.

Here we explore the association between killer cell immunoglobulin-like receptor (KIR)/HLA and human immunodeficiency virus type 1 (HIV-1) acquisition with different viral subtypes circulating in East Africa. In the prospective Cohort Development (CODE) cohort (Mbeya, Tanzania), carriers of KIR3DS1 and its putative ligand (HLA-A or HLA-B Bw4-80Ile alleles) showed increased HIV-1 acquisition risk (odds ratio [OR] = 3.46; 95% confidence interval [CI], 1.12-10.63; P = .04) and a trend for enrichment for subtype A and A-containing recombinants (78% vs. 46%; OR = 4.05; 95% CI, .91-28.30; P = .09) at the expense of subtype C (11% vs. 43%; OR = 0.17; 95% CI, .01-.97; P = .08). In vitro, only natural killer cells from KIR3DS1(+)/HLA-Bw4-80Ile(+) healthy donors showed a 2-fold increased capacity to inhibit replication of subtype C vs subtype A viruses (P = .01). These findings suggest the presence of an innate sieve effect and may inform HIV-1 vaccine development.

The multi-region hybridization assay (MHAbce) for genotyping HIV-1 subtypes B, C and circulating recombinant form (CRF01_AE) was evaluated on paired plasma and dried blood spots (DBS) collected from 68 HIV-1 infected individuals in Thailand. CRF01_AE was the predominant subtype identified using plasma samples (51/62) and DBS (24/27). There was no discordance in subtype designations between plasma and DBS.

The U.S. Army initiated an investigation in response to observations of a possible increase in HIV incidence among soldiers deployed to combat. Human immunodeficiency virus (HIV)-infected U.S. Army soldiers are not eligible to deploy. Combat presents a health hazard to HIV-infected soldiers and they pose a threat to the safety of the battlefield blood supply and their contacts. All soldiers are routinely screened for HIV every 2 years and those who deploy are also screened both prior to and after deployment. Seroconversion rates were estimated for all soldiers who deployed to Afghanistan or Iraq in the period 2001-2007 and all active duty soldiers who did not. Seroconverters with an estimated date of infection, based on calculation of the midpoint between the last seronegative and first seropositive test date, that was either before or during deployment were eligible for inclusion. Confidential interviews and medical record reviews were conducted to determine the most likely time, geographic location, and mode of infection. Reposed predeployment samples were tested for HIV ribonucleic acid. The HIV seroconversion rate among all soldiers who deployed was less than the rate among those who did not deploy: 1.04 and 1.42 per 10,000 person-years, respectively. Among 48 cases, most were determined to have been infected in the United States or Germany and prior to deployment (n=20, 42%) or during rest and relaxation leave (n=13, 27%). Seven seronegative acute infections were identified in the predeployment period. Subtype was determined for 40 individuals; all were subtype B infections. All were acquired through sexual contact. These findings can inform development of preventive interventions and refinement of existing screening policy to further reduce HIV-infected deployed soldier person time.

Background: Dual infection with diverse HIV strains can foster the emergence of recombinants. The resulting increase in viral genetic diversity is a major challenge for vaccine development HIV treatment. In this study we aim to investigate the socio demographic factors associated with an increasing level of genetic diversity among HIV strains in a population of drug-users in Northern Thailand.Methods: From 1999 through 2000,2231 volunteers were enrolled in the Opiate-Users Research in Chiang Mai, Thailand. HIV subtype analysis was conducted among those HIV-1 seropositive (n = 347) using a multi-region hybridization assay. Social and demographic variables were assessed using a structured questionnaire.Results: Overall, 336/347 (96.8%) of the samples could be typed. 81.8% were CRF01_AE, 3.9% were subtype B, 9.2% were recombinants (mostly between CRF01_AE and B) and 5.1% were dual infections. Dual infections were more frequent among those with a lower education level (AOR: 5.2; 95% Cl 1.4-20.3), those who have initiated injecting in the last 3 years (AOR: 3.9; 95% Cl 1.1-14.6), and those reporting frequent needle sharing in the last 3 months (AOR: 7.0; 95% Cl 1.5-34.1). Both recombinant strains and dual infection were more frequent among those reporting frequent needle sharing in the last 3 months (AOR: 5.3; 95% CI 1.6-17.1).Conclusion: To limit the expanding complexity of HIV-1 strains, early intervention should be aimed at reduction in needle sharing, especially among new intravenous drug users. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

Koup Maboko, Michael Hoelscher, Francine McCutchan, David A. Price, Daniel C. Douek and Richard A. Leonard Ambrozak, Constantinos Petrovas, Alexandra Schuetz, Njabulo Ngwenyama, Gustavo Kijak, Christof Geldmacher, Ian S. Metzler, Sodsai Tovanabutra, Tedi E. Asher, Emma Gostick, David R. biologic outcome of an epitope-specific CD8 T-cell response Minor viral and host genetic polymorphisms can dramatically impact the

Background: CRF14_BG isolates, originally found in Spain, are characterized by CXCR4 tropism and rapid disease progression. This study aimed to identify the origin of CRF14_BG and reconstruct its epidemiological history based on new isolates from Portugal.Methodology/Principal Findings: C2V3C3 env gene sequences were obtained from 62 samples collected in 1993-1998 from Portuguese HIV-1 patients. Full-length genomic sequences were obtained from three patients. Viral subtypes, diversity, divergence rate and positive selection were investigated by phylogenetic analysis. The molecular structure of the genomes was determined by bootscanning. A relaxed molecular clock model was used to date the origin of CRF14_BG. Geno2pheno was used to predict viral tropism. Subtype B was the most prevalent subtype (45 sequences; 73%) followed by CRF14_BG (8; 13%), G (4; 6%), F1 (2; 3%), C (2; 3%) and CRF02_AG (1; 2%). Three CRF14_BG sequences were derived from 1993 samples. Near full-length genomic sequences were strongly related to the CRF14_BG isolates from Spain. Genetic diversity of the Portuguese isolates was significantly higher than the Spanish isolates (0.044 vs 0.014, P<0.0001). The mean date of origin of the CRF14_BG cluster was estimated to be 1992 (range, 1989 and 1996) based on the subtype G genomic region and 1989 (range, 1984-1993) based on the subtype B genomic region. Most CRF14_BG strains (78.9%) were predicted to be CXCR4. Finally, up to five amino acids were under selective pressure in subtype B V3 loop whereas only one was found in the CRF14_BG cluster.Conclusions: CRF14_BG emerged in Portugal in the early 1990 s soon after the beginning of the HIV-1 epidemics, spread to Spain in late 1990 s as a consequence of IVDUs migration and then to the rest of Europe. CXCR4 tropism is a general characteristic of this CRF that may have been selected for by escape from neutralizing antibody response.

We analyzed HIV-1 genome sequences from 68 newly infected volunteers in the STEP HIV-1 vaccine trial. To determine whether the vaccine exerted selective T cell pressure on breakthrough viruses, we identified potential T cell epitopes in the founder sequences and compared them to epitopes in the vaccine. We found greater distances to the vaccine sequence for sequences from vaccine recipients than from placebo recipients. The most significant signature site distinguishing vaccine from placebo recipients was Gag amino acid 84, a site encompassed by several epitopes contained in the vaccine and restricted by human leukocyte antigen (HLA) alleles common in the study cohort. Moreover, the extended divergence was confined to the vaccine components of the virus (HIV-1 Gag, Pol and Nef) and not found in other HIV-1 proteins. These results represent what is to our knowledge the first evidence of selective pressure from vaccine-induced T cell responses on HIV-1 infection in humans.