Project description:During sexual transmission of HIV-1 from male to female partners, the vagina is the initial site of contact with HIV infected semen. The mechanism of HIV traversing the CD4 negative multi-layered stratified squamous epithelial barrier of the vagina to infect sub-epithelial susceptible immune cells, is hitherto unknown. HIV gp120 binds to several host proteins on vaginal epithelial cells. To gain an insight into the physiologic changes that may occur in vaginal epithelial cells in response to interactions with HIV gp120, and obtain an understanding of the molecular mechanisms by which HIV breaches the vaginal epithelium, a global snap shot of gene expression profiles in the vaginal epithelial cell line Vk2/E6E7, treated with HIV gp120 was determined. The vaginal epithelial cell line Vk2/E6E7 was treated with HIV gp120 (83nM) for 24 hr, and Agilent one colour, microarrays were performed.
Project description:During sexual transmission of HIV-1 from male to female partners, the vagina is the initial site of contact with HIV infected semen. The mechanism of HIV traversing the CD4 negative multi-layered stratified squamous epithelial barrier of the vagina to infect sub-epithelial susceptible immune cells, is hitherto unknown. HIV gp120 binds to several host proteins on vaginal epithelial cells. To gain an insight into the physiologic changes that may occur in vaginal epithelial cells in response to interactions with HIV gp120, and obtain an understanding of the molecular mechanisms by which HIV breaches the vaginal epithelium, a global snap shot of gene expression profiles in the vaginal epithelial cell line Vk2/E6E7, treated with HIV gp120 was determined. The vaginal epithelial cell line Vk2/E6E7 was treated with HIV gp120 (83nM) for 24 hr, and Agilent one colour, microarrays were performed. Agilent one-color experiment,Organism: Human ,Agilent-Custom Whole Genome Human 8x60k designed by Genotypic Technology Pvt. Ltd. (AMADID: 027114), Labeling kit: Agilent Quick-Amp labeling Kit (p/n5190-0442)
Project description:The hormonal contraceptive medroxyprogesterone acetate (MPA) is associated with increased risk of human immunodeficiency virus (HIV), via incompletely understood mechanisms. Increased diversity in the vaginal microbiota modulates genital inflammation and is associated with increased HIV-1 acquisition. However, the effect of MPA on diversity of the vaginal microbiota is relatively unknown. In a cohort of female Kenyan sex workers, negative for sexually transmitted infections (STIs), with Nugent scores <7 (N=58 of 370 screened), MPA correlated with significantly increased diversity of the vaginal microbiota as assessed by 16S rRNA gene sequencing. MPA was also significantly associated with decreased levels of estrogen in the plasma, and low vaginal glycogen and α-amylase, factors implicated in vaginal colonization by lactobacilli, bacteria that are believed to protect against STIs. In a humanized mouse model, MPA treatment was associated with low serum estrogen, low glycogen and enhanced HIV-1 susceptibility. The mechanism by which the MPA mediated changes in the vaginal microbiota may contribute to HIV-1 susceptibility in humans appears to be independent of inflammatory cytokines and/or activated T cells. Altogether, these results suggest MPA-induced hypo-estrogenism may alter key metabolic components that are necessary for vaginal colonization by certain bacterial species including lactobacilli, and allow for greater bacterial diversity in the vaginal microbiota.
Project description:The anti-HIV humoral immune response following acute infection is delayed and ineffective. HIV envelope protein gp120 binds to and signals through α4β7 on T cells. We show that gp120 also binds and signals through α4β7 on B cells, resulting in an abortive proliferative response. In primary B cells, gp120 signaling through α4β7 resulted in increased expression of TGF-β1 and the B cell inhibitory receptor FcRL4. Co-culture of B cells with HIV-infected autologous CD4+ T cells also resulted in increased B cell FcRL4 expression. These findings indicate that, in addition to inducing chronic immune activation, viral proteins can contribute directly to HIV-associated B cell dysfunction, thus providing a mechanism whereby the virus subverts the early HIV-specific humoral immune response.
Project description:The anti-HIV humoral immune response following acute infection is delayed and ineffective. HIV envelope protein gp120 binds to and signals through α4β7 on T cells. We show that gp120 also binds and signals through α4β7 on B cells, resulting in an abortive proliferative response. In primary B cells, gp120 signaling through α4β7 resulted in increased expression of TGF-β1 and the B cell inhibitory receptor FcRL4. Co-culture of B cells with HIV-infected autologous CD4+ T cells also resulted in increased B cell FcRL4 expression. These findings indicate that, in addition to inducing chronic immune activation, viral proteins can contribute directly to HIV-associated B cell dysfunction, thus providing a mechanism whereby the virus subverts the early HIV-specific humoral immune response. Forty-two samples in two batches were run with different treatments and different time points.