Objective-To estimate the prevalence of HIV and hepatitis C virus (HCV) and hepatitis B virus (HBV) co-infection as well as current risk behaviors among HIV positive and negative injection drug users (IDUs) in Chennai, India.
Methods
Broadly neutralizing antibodies isolated from infected patients who are elite neutralizers have identified targets on HIV-1 envelope (Env) glycoprotein that are vulnerable to antibody neutralization; however, it is not known whether infection established by the majority of the circulating clade C strains in Indian patients elicit neutralizing antibody responses against any of the known targets. In the present study, we examined the specificity of a broad and potent cross-neutralizing plasma obtained from an Indian elite neutralizer infected with HIV-1 clade C. This plasma neutralized 53/57 (93%) HIV pseudoviruses prepared with Env from distinct HIV clades of different geographical origins. Mapping studies using gp120 core protein, single-residue knockout mutants, and chimeric viruses revealed that G37080 broadly cross-neutralizing (BCN) plasma lacks specificities to the CD4 binding site, gp41 membrane-proximal external region, N160 and N332 glycans, and R166 and K169 in the V1-V3 region and are known predominant targets for BCN antibodies. Depletion of G37080 plasma with soluble trimeric BG505-SOSIP.664 Env (but with neither monomeric gp120 nor clade C membrane-proximal external region peptides) resulted in significant reduction of virus neutralization, suggesting that G37080 BCN antibodies mainly target epitopes on cleaved trimeric Env. Further examination of autologous circulating Envs revealed the association of mutation of residues in the V1 loop that contributed to neutralization resistance. In summary, we report the identification of plasma antibodies from a clade C-infected elite neutralizer that mediate neutralization breadth via epitopes on trimeric gp120 not yet reported and confer autologous neutralization escape via mutation of residues in the V1 loop.
IMPORTANCEA preventive vaccine to protect against HIV-1 is urgently needed. HIV-1 envelope glycoproteins are targets of neutralizing antibodies and represent a key component for immunogen design. The mapping of epitopes on viral envelopes vulnerable to immune evasion will aid in defining targets of vaccine immunogens. We identified novel conformational epitopes on the viral envelope targeted by broadly cross-neutralizing antibodies elicited in natural infection in an elite neutralizer infected with HIV-1 clade C. Our data extend our knowledge on neutralizing epitopes associated with virus escape and potentially contribute to immunogen design and antibody-based prophylactic therapy.
The predominance of HCV genotype 1b among CLD patients could pose a major challenge for the efficient management of HCV disease and the development of effective therapeutic interventions in peninsular India.
Background
The role of T-cell responses against Mycobacterium tuberculosis antigens in tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) is unclear.
Methods
Peripheral blood mononuclear cells from 45 HIV patients with treated TB, of whom 12 developed TB-IRIS, were collected at weeks 0, 2, and 6 of antiretroviral therapy (ART). Production of interferon-γ (IFN-[γ]) and interleukin-2 by T cells after stimulation with purified protein derivative (PPD) or early secretory antigenic target-6 (ESAT-6) and T-cell expressions of CCR5 and CXCR3 were assessed by flow cytometry. IFN-γ and CXCL10 were assayed by enzyme-linked immunosorbent assay.
Results
TB-IRIS patients had higher proportions of PPD- and ESAT-6–reactive IFN-γ+CD4+ and CD3+CD4- T cells at weeks 0, 2, and 6. IFN-γ levels were also higher in peripheral blood mononuclear cell culture supernatants at all times with PPD but only at weeks 2 and 6 with ESAT-6. There were few differences for interleukin-2. CXCL10 levels in supernatants after PPD and ESAT-6 stimulation were only higher at week 6. CXCR3+/CCR5+CD4+ T cells were higher at week 2, and CCR5+CD4+ T cells were higher at week 6.
Conclusions
TB-IRIS is associated with Th1 responses against M. tuberculosis antigens by CD4+ and CD3+CD4- T cells that are present before ART and amplified afterward. It is unclear if these cause immunopathology or reflect a high pathogen load.
We investigated 245 diarrheal stool specimens from HIV-positive subjects between January 2003 and December 2006 to determine the etiological role of coproparasites. Parasitic etiology was observed in 91 (37.1%) cases. Isospora belli (26.1%) was the most common parasite followed by Entameba histolytica/dispar (3.3%), Cryptosporidium spp. (2.9%), Giardia intestinalis (1.6%), and Strongyloides stercoralis (1.2%). Interesting trends of significant increase in the number of cases of I. belli and decline in Cryptosporidium spp. were observed during the study period.
BackgroundIt is estimated that there are up to 1.1 million injection drug users (IDUs) in India; the majority are likely married. We characterize HIV, hepatitis B (HBV) and hepatitis C (HCV) prevalence and the risk environment of a sample of spouses of IDUs.MethodsA cohort of 1158 IDUs (99% male) was recruited in Chennai, India from 2005-06. A convenience sample of 400 spouses of the male IDUs in this cohort was recruited in 2009. A risk assessment questionnaire was administered and a blood sample collected. Logistic regression was used to identify factors associated with prevalent HIV.ResultsMedian age was 31 years; thirteen percent were widowed and 7% were not currently living with their spouse. Only 4 (1%) reported ever injecting drugs; Twenty-two percent and 25% reported ever using non-injection drugs and alcohol, respectively. The majority had one lifetime sexual partner and 37 (9%) reporting exchanging sex. Only 7% always used condoms with their regular partner. HIV, HBV and HCV prevalence were 2.5%, 3.8% and 0.5%, respectively; among spouses of HIV+ IDUs (n = 78), HIV prevalence was 10.3%. The strongest predictor of HIV was spousal HIV status (OR: 17.9; p < 0.001). Fifty-six percent of women had ever experienced intimate partner violence; Eight-six percent reported sexual violence.ConclusionsOur finding of a 10-fold higher HIV prevalence among spouses of IDUs compared with general population women indicates their vulnerability; prevalence is likely to increase given the context of low condom use and frequent sexual violence. Prevention efforts directed at IDUs should also include programs for spouses.
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