Search

Human immunodeficiency virus 1 (HIV-1) exposed seronegative (HESN) individuals may have unique characteristics that alter susceptibility to HIV-1 infection. However, identifying truly exposed HESN is challenging. We utilized stored data and biospecimens from HIV-1 serodifferent couple cohorts, in which couples' HIV-1 exposures were quantified based on unprotected sex frequency and viral load of the partner with HIV-1. We compared peripheral blood gene expression between 15 HESN and 18 seroconverters prior to infection. We found PTPRC (encoding CD45 antigen) and interferon-response pathways had significantly higher expression among individuals who went on to become seropositive and thus may be a signature for increased acquisition risk. [ABSTRACT FROM AUTHOR]

The predictors of loss to follow-up (LTFU) in trials of candidate HIV preventive vaccines are determined from the data obtained from trials conducted by the AIDS Vaccine Evaluation Group (AVEG) and HIV Network for Prevention Trials (HIVNET). Younger age and increasing trial duration predicted LTFU.

Background: HIV prevention trials are increasingly being conducted in sub-Saharan Africa. Women at risk for HIV are also at risk of pregnancy. To maximize safety, women agree to avoid pregnancy during trials, yet pregnancies occur. Using data from the HVTN 503/"Phambili" vaccine trial, we report pregnancy incidence during and after the vaccination period and identify factors, measured at screening, associated with incident pregnancy. Methods: To enrol in the trial, women agreed and were supported to avoid pregnancy until 1 month after their third and final vaccination ("vaccination period"), corresponding to the first 7 months of follow-up. Unsterilized women, pooled across study arms, were analyzed. Poisson regression compared pregnancy rates during and after the vaccination period. Cox proportional hazards regression identified associations with first pregnancy. Results: Among 352 women (median age 23 yrs; median follow-up 1.5 yrs), pregnancy incidence was 9.6/100 women-years overall and 6.8/100 w-yrs and 11.3/100 w-yrs during and after the vaccination period, respectively [Rate Ratio = 0.60 (0.32-1.14), p = 0.10]. In multivariable analysis, pregnancy was reduced among women who: enrolled at sites providing contraception on-site [HR = 0.43, 95% CI (0.22-0.86)]; entered the trial as injectable contraceptive users [HR = 0.37 (0.21-0.67)] or as consistent condom users (trend) [HR = 0.54 (0.28-1.04)]. Compared with women with a single partner of HIV-unknown status, pregnancy rates were increased among women with: a single partner whose status was HIV-negative [HR = 2.34(1.16-4.73)] and; 2 partners both of HIV-unknown status [HR = 4.42(1.59-12.29)]. Women with 2 more of these risk factors: marijuana use, heavy drinking, or use of either during sex, had increased pregnancy incidence [HR = 2.66 (1.24-5.72)]. Conclusions: It is possible to screen South African women for pregnancy risk at trial entry. Providing injectable contraception for free on-site and supporting consistent condom use may reduce incident pregnancy. Screening should determine the substance use, partnering, and HIV status of both members of the couple for both pregnancy and HIV prevention. [ABSTRACT FROM AUTHOR]

Background: The risk of HIV-1 related mortality is strongly related to CD4 count. Guidance on optimal timing for initiation of antiretroviral therapy (ART) is still evolving, but the contribution of HIV-1 infection to excess mortality at CD4 cell counts above thresholds for HIV-1 treatment has not been fully described, especially in resource-poor settings. To compare mortality among HIV-1 infected and uninfected members of HIV-1 serodiscordant couples followed for up to 24 months, we conducted a secondary data analysis examining mortality among HIV-1 serodiscordant couples participating in a multicenter, randomized controlled trial at 14 sites in seven sub-Saharan African countries. Methods: Predictors of death were examined using Cox regression and excess mortality by CD4 count and plasma HIV-1 RNA was computed using Poisson regression for correlated data. Results: Among 3295 HIV serodiscordant couples, we observed 109 deaths from any cause (74 deaths among HIV-1 infected and 25 among HIV-1 uninfected persons). Among HIV-1 infected persons, the risk of death increased with lower CD4 count and higher plasma viral levels. HIV-1 infected persons had excess mortality due to medical causes of 15.2 deaths/1000 person years at CD4 counts of 250 - 349 cells/µl and 8.9 deaths at CD4 counts of 350 - 499 cells/µl. Above a CD4 count of 500 cells/µl, mortality was comparable among HIV-1 infected and uninfected persons. Conclusions: Among African serodiscordant couples, there is a high rate of mortality attributable to HIV-1 infection at CD4 counts above the current threshold (200 - 350 cells/µl) for ART initiation in many African countries. These data indicate that earlier initiation of treatment is likely to provide clinical benefit if further expansion of ART access can be achieved. [ABSTRACT FROM AUTHOR]

Background. Knowledge of factors that affect per-act infectivity of human immunodeficiency virus type 1 (HIV-1) is important for designing HIV-1 prevention interventions and for the mathematical modeling of the spread of HIV-1. Methods. We analyzed data from a prospective study of African HIV-1-serodiscordant couples. We assessed transmissions for linkage within the study partnership, based on HIV-1 sequencing. The primary exposure measure was the HIV-1-seropositive partners' reports of number of sex acts and condom use with their study partner. Results. Of 3297 couples experiencing 86 linked HIV-1 transmissions, the unadjusted per-act risks of unprotected male-to-female (MTF) and female-to-male (FTM) transmission were 0.0019 (95% confidence interval [CI], .0010-.0037) and 0.0010 (95% CI, .00060-.0017), respectively. After adjusting for plasma HIV-1 RNA of the HIV-1-infected partner and herpes simplex virus type 2 serostatus and age of the HIV-1-uninfected partner, we calculated the relative risk (RR) for MTF versus FTM transmission to be 1.03 (P 5 .93). Each log10 increase in plasma HIV-1 RNA increased the per-act risk of transmission by 2.9-fold (95% CI, 2.2-3.8). Self-reported condom use reduced the per-act risk by 78% (RR 5 0.22 [95% CI, .11-.42]). Conclusions. Modifiable risk factors for HIV-1 transmission were plasma HIV-1 RNA level and condom use, and, in HIV-1-uninfected partners, herpes simplex virus 2 infection, genital ulcers, Trichomonas vaginalis, vaginitis or cervicitis, and male circumcision. [ABSTRACT FROM AUTHOR]

Background In the context of a multisite HIV prevention trial in Southern African women, we examined the effectiveness of the Ortho All-Flex Diaphragm, lubricant gel (Replens) and condoms compared to condoms alone on the incidence of herpes simplex virus type 2 (HSV-2) infections. Methods We analysed data from 2016 sexually active women in Zimbabwe and South Africa. Women were followed quarterly, and specimens obtained at the closing visit from previously HSV-2 seronegative women were retested for HSV-2 antibodies using Focus HerpeSelect Elisa. The first visit at which the participant tested positive for HSV-2 was defined by back-testing. We compared the incidence of HSV-2 after randomisation between study arms in both intent-to-treat (ITT) and per-protocol populations. Results 210 women acquired HSV-2 during study participation (HSV incidence: 6.8 cases/100 women years). Allocation to the intervention arm was found to offer no benefit in reduction of HSV-2 by modified ITT (HR 1.03, 95% CI 0.78 to 1.35; p=0.85) or per protocol analysis (HR 0.87, 95% CI 0.61 to 1.24; p=0.45). Conclusions HSV-2 infection was common in the study population as detected by type-specific Elisa testing. Provision of diaphragm and lubricant gel offered no additional protection against HSV-2 acquisition over male condoms alone. Trial Registration http://ClinicalTrials.gov; number NCT00121459. [ABSTRACT FROM AUTHOR]

The generation of polyfunctional CD8+T cells, in response to vaccination or natural infection, has been associated with improved protective immunity. However, it is unclear whether the maintenance of polyfunctionality is related to particular cellular phe-notypic characteristics. To determine whether the cytokine expression profile is linked to the memory differentiation stage, we analyzed the degree of polyfunctionality of HIV-specific CD8+T cells within different memory subpopulations in 20 antiretro-viral therapy-naive HIV-l-infected individuals at 34 wk postinfection. These profiles were compared with CMV-specific CD8+ T cell responses in HIV-uninfected control subjects and in individuals chronically infected with HIV. Our results showed that the polyfunctional abilities of HIV-specific CD8+ T cells differed according to their memory phenotype. Early-differentiated cells (CD45RO+CD27+) exhibited a higher proportion of cells positive for three or four functions (p < 0.001), and a lower proportion of monofunctional cells (p < 0.001) compared with terminally differentiated (TD; CD45RO-CD27-) HIV-specific CD8+T cells. The majority of TD HIV-specific CD8+ T cells were monofunctional (median 69% [interquartile range: 57-83]), producing predominantly CD107a or MIPip. Moreover, proportions of HIV-specific monofunctional CD8+ T cells positively associated with proportions of TD HIV-specific CD8+ T cells (p = 0.019, r = 0.54). In contrast, CMV-specific CD8+ T cell polyfunctional capacities were similar across all memory subpopulations, with terminally and early-differentiated cells endowed with compa-rable polyfunctionality. Overall, these data show that the polyfunctional abilities of HIV-specific CD8+ T cells are influenced by the stage of memory differentiation, which is not the case for CMV-specific responses. [ABSTRACT FROM AUTHOR]