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Background. To date, onlymutations in CCR5 have been shown to confer resistance to human immunodeficiency virus type 1 (HIV-1) infection, and these explain only a small fraction of the observed variability in HIV susceptibility. Methods. We performed a meta-analysis between 2 independent European genomewide association studies, each comparing HIV-1 seropositive cases with normal population controls known to be HIV uninfected, to identify single-nucleotide polymorphisms (SNPs) associated with the HIV-1 acquisition phenotype. SNPs exhibiting P < 10-5 in this first stage underwent second-stage analysis in 2 independent US cohorts of European descent. Results. After the first stage, a single highly significant association was revealed for the chromosome 8 rs6996198 with HIV-1 acquisition and was replicated in both second-stage cohorts. Across the 4 groups, the rs6996198-T allele was consistently associated with a significant reduced risk of HIV-1 infection, and the global meta-analysis reached genomewide significance: Pcombined = 7.76 × 10-8. Conclusions. We provide strong evidence of association for a common variant with HIV-1 acquisition in populations of European ancestry. This protective signal against HIV-1 infection is the first identified outside the CCR5 nexus. First clues point to a potential functional role for a nearby candidate gene, CYP7B1, but this locus warrants further investigation. [ABSTRACT FROM AUTHOR]

A recent genome-wide study showed that the single nucleotide polymorphisms (SNPs) in the HLA-DP region were associated with chronic hepatitis B virus (HBV) infection in Japanese and Thai persons. We tested the effects of HLA-DP SNPs for all major HBV outcomes in Han Chinese (n = 1742): HBV resistance, clearance, chronic infection, cirrhosis, and hepatocellular carcinoma. HLA - DPA1 rs3077 T was strongly associated with decreased risk of chronic HBV infection (odds ratio, .62; P = .001), consistent with the previous report. We showed for the first time to our knowledge that it is a predictor for HBV clearance (odds ratio, 2.41; P < .001). However, rs3077 was not associated with the development of cirrhosis or hepatocellular carcinoma. [ABSTRACT FROM PUBLISHER]

Background. High-throughput genome-wide techniques have facilitated the identification of previously unknown host proteins involved in cellular human immunodeficiency virus (HIV) infection. Recently, 3 independent studies have used small interfering RNA technology to silence each gene in the human genome to determine the importance of each in HIV infection. Genes conferring a significant effect were termed HIV-dependency factors (HDFs). Methods. We assembled high-density panels of 6380 single-nucleotide polymorphisms (SNPs) in 278 HDF genes and tested for genotype associations with HIV infection and AIDS progression in 1633 individuals from clinical AIDS cohorts. Results. After statistical correction for multiple tests, significant associations with HIV acquisition were found for SNPs in 2 genes, NCOR2 and IDH1. Weaker associations with AIDS progression were revealed for SNPs within the TM9SF2 and EGFR genes. Conclusions. This study independently verifies the influence of NCOR2 and IDH1 on HIV transmission, and its findings suggest that variation in these genes affects susceptibility to HIV infection in exposed individuals. [ABSTRACT FROM AUTHOR]

Background: Cytomegalovirus (CMV) retinitis is a common opportunistic infection among patients with AIDS and still causes visual morbidity despite the wide spread usage of highly active antiretroviral therapy (HAART). The ubiquitous CMV pathogen contains a human interleukin-10 (IL-10) homolog in its genome and utilizes it to evade host immune reactions through an IL-10 receptor mediated immune-suppression pathway.Methods: Effects of IL-10R1, IL-10 and previously described AIDS restriction gene variants are investigated on the development of CMV retinitis in the Longitudinal Study of the Ocular Complications of AIDS (LSOCA) cohort (N = 1284).Results: In European Americans (n = 750), a haplotype carrying an amino acid changing variation in the cytoplasmic domain (S420L) of IL-10R1 can be protective (OR, 0.14; 95% CI, 0.02-0.94; P = .04) against, whereas another haplotype carrying an amino acid changing variation in the extracellular domain (I224V) of IL-10R1 can be more susceptible (OR, 6.21; 95% CI, 1.22- 31.54; P = .03) to CMV retinitis. In African Americans (n = 534), potential effects of IL-10 variants are observed.Conclusion: Host genetics may have a role in the occurrence of CMV retinitis in patients infected with HIV. [ABSTRACT FROM AUTHOR]

Background. Cytomegalovirus (CMV) retinitis is a common opportunistic infection among patients with AIDS and still causes visual morbidity despite the wide spread usage of highly active antiretroviral therapy (HAART). The ubiquitous CMV pathogen contains a human interleukin-10 (IL-10) homolog in its genome and utilizes it to evade host immune reactions through an IL- 10 receptor mediated immune-suppression pathway. Methods. Effects of IL-10R1, IL-10 and previously described AIDS restriction gene variants are investigated on the development of CMV retinitis in the Longitudinal Study of the Ocular Complications of AIDS (LSOCA) cohort (N 1284). Results. In European Americans (n = 750), a haplotype carrying an amino acid changing variation in the cytoplasmic domain (S420L) of IL-10R1 can be protective (OR, 0.14; 95% CI, 0.02-0.94; P = .04) against, whereas another haplotype carrying an amino acid changing variation in the extracellular domain (1224V) of IL-10R1 can be more susceptible (OR, 6.21; 95% CI, 1.22- 31.54; P = .03) to CMV retinitis. In African Americans (n = 534), potential effects of IL-10 variants are observed. Conclusion. Host genetics may have a role in the occurrence of CMV retinitis in patients infected with HIV. [ABSTRACT FROM AUTHOR]

Background. A mean of 9-10 years of human immunodeficiency virus type 1 (HIV-1) infection elapse before clinical AIDS develops in untreated persons, but this rate of disease progression varies substantially among individuals. To investigate host genetic determinants of the rate of progression to clinical AIDS, we performed a multistage genomewide association study. Methods. The discovery stage comprised 156 individuals from the Multicenter AIDS Cohort Study, enriched with rapid and long-term nonprogressors to increase statistical power. This was followed by replication tests of putatively associated genotypes in an independent population of 590 HIV-1-infected seroconverters. Results. Significant associations with delayed AIDS progression were observed in a haplotype located at 1q41, 36 kb upstream of PROX1 on chromosome 1 (relative hazard ratio, 0.69; Fisher's combined P=6.23×10-7). This association was replicated further in an analysis stratified by transmission mode, with the effect consistent in sexual or mucosal and parenteral transmission (relative hazard ratios, 0.72 and 0.63, respectively; combined P=1.63×10-6). Conclusions. This study identified and replicated a locus upstream of PROX1 that is associated with delayed progression to clinical AIDS. PROX1 is a negative regulator of interferon-γ expression in T cells and also mitigates the advancement of vascular neoplasms, such as Kaposi sarcoma, a common AIDS-defining malignancy. This study adds to the cumulative polygenic host component that effectively regulates the progression to clinical AIDS among HIV-1-infected individuals, raising prospects for potential new avenues for therapy and improvements in AIDS prognosis. [ABSTRACT FROM AUTHOR]

Background. Some individuals are readily infected with low human immunodeficiency virus type 1 (HIV-1) exposure, whereas others appear less susceptible, suggesting that host genetics plays a role in the viral entry pathway. The matched case-control study design with measured risk exposures provides an avenue for discovering genes involved in susceptibility to infection. Methods. We conducted a nested case-control study of African Americans (266 HIV-1 seroconverter cases and 532 seronegative controls from the AIDS Link to Intravenous Experience cohort), to examine the association between 50 single-nucleotide polymorphisms (SNPs) in 9 candidate genes (CCR5, CCR2, RANTES, MIPIA, MCP2, ILl0, IFNG, MCSF, and 1L2) and susceptibility to HIV-1 infection. To account for differential exposure propensities, risk behavior self-reported during semiannual visits was used to estimate a standardized cumulative risk exposure (SGRE). Individual SNPs were evaluated using conditional logistic-regression models, and the inferred haplotypes were assessed in the haplotype trend regression analyses after adjusting for age and SGRE. Results. Four SNPs (CCR2-V641, CCR5- 2459, MIPJA+954, and 1L2+3896) and specific haplotypes in the 1L2 and CCR2/CCR5 regions were significantly associated with HIV-1 infection susceptibility in different genetic models. Conclusions. Our results suggest that genetic variants in associated host genes may play an important role in susceptibility to HIV-1 infection. [ABSTRACT FROM AUTHOR]

This study used a well characterized cohort of human immunodeficiency virus type 1 (HIV-1)-infected hemophiliacs to define the relationship between the SDF1-3'A allele, the plasma HIV-1 coreceptor tropism, and the natural history of HIV-1 disease. Subjects heterozygous or homozygous for the SDF1-3'A allele experienced higher rates of decline in CD4+ T cell counts over time than did those without the allele (P = .009). Moreover, they had an increased risk of progression to acquired immunodeficiency syndrome and death, a relationship that persisted even when baseline plasma HIV-1 RNA levels and CD4+ T cell counts or CCR5Δ32 and CCR2- 64I genotype were controlled for. This relationship was even stronger in a subgroup of subjects for whom tropism data were available. Subjects with the SDF1-3'A allele were also more likely to have detectable X4- tropic viruses (P = .012), and, when tropism was included in the survival analyses, the effect of the SDF1-3'A allele on disease progression was no longer significant. Therefore, the increased frequency of X4-tropic viruses in subjects carrying the SDF1-3'A allele may explain the observed adverse effect that this allele has on the natural history of HIV-1 disease. [ABSTRACT FROM AUTHOR]

A polymorphism, 3179G/T, in the promoter of the interferon (IFN)-γ gene (IFNG) confers differential tumor necrosis factor-α (TNF-α) inducibility to the IFNG promoter. The rarer allele, 3179T, but not 3179G, is inducible by TNF-α. We investigated the effects of IFNG 3179G/T on AIDS pathogenesis. In 298 African American human immunodeficiency virus (HIV)-1 seroconverters, the IFNG 3179G/T genotype was associated with accelerated progression to CD4<200 and AIDS-1993, a finding suggesting that IFNG 3179T is a risk factor for AIDS progression, as measured by CD4 cell count. It is possible that increased IFN-γ production induced by TNF-α when 3179T is present causes CD4 cell depletion by apoptosis. [ABSTRACT FROM AUTHOR]

Examines the relationship of human leukocyte antigen (HLA) class I and transporter associated with antigen processing genes with resistance to HIV-1 infection. Effect of the presence of the subgroup alleles; Possibility for the differential preferences for amino acids at the C terminus to influence peptide-binding capacity.

Presents several comments related to different diseases and viruses. Association between human leukocyte antigen and hepatitis C virus; Combination of vaccines for the treatment of human immunodeficiency virus; Production of an immune response against exoenzyme S.

Discusses racial differences in human leukocyte antigen (HLA) class II associated with hepatitis C virus. Characteristics of HLA; Discussion on a serologic testing; Association with black patients.

Features a study which examined human immunodeficiency virus type 1/hepatitis C virus (HIV-1/HCV)-coninfected patients to assess the interaction between HCV load and HIV-1 disease progression. Measurements of HIV-1 and HCV RNA concentrations; Statistical methods; Results; Discussion.

Seven long-term nonprogressors (LTNPs) have been identified in a cohort of 128 human immunodeficiency virus (HIV)-1infected individuals with hemophilia. Studies included quantitation of virus by polymerase chain reaction, characterization of primary virus isolates in vitro, analysis of lymphocyte surface markers, and measurement of virus-specific cytotoxic T lymphocytes (CTLs). Viruses of LTNPs exhibited slow growth in vivo and in vitro. LTNPs had expansion of CD8 T cells with increased expression of HLA-DR. Intermittent HIV-1-specific CTL effector activity was detected in freshly isolated peripheral blood mononuclear cells of most LTNPs. CTL precursor frequencies were higher in LTNPs than in patients with progressive disease. Virus antigen-specific lymphoproliferation was vigorous in some LTNPs. Thus, LTNPs in this cohort have maintained remarkably low virus burdens and vigorous HIV-1-specific cell-mediated immunity over a 15-year period. The presence of expanded, activated CD8 T cells with cytotoxic effector function in the peripheral blood suggests ongoing viral replication. [ABSTRACT FROM AUTHOR]

Examines the persistence of class II human leukocytes antigen (HLA) in alleles and hepatitis B virus (HBV) in Afro-Americans in Baltimore, Maryland. Factor contributing to the persistence of HBV infection; Effect of allelic differences in HLA complex on HBV persistence; Association of HBV persistence with class II allelic homozygosity.