Non-Cationic Proteins Are Associated with HIV Neutralizing Activity in Genital Secretions of Female Sex Workers.

Objective: Cationic proteins found in cervicovaginal secretions (CVS) are known to contribute to the early antiviral immune response against HIV-infection in vitro. We here aimed to define additional antiviral factors that are over-expressed in CVS from female sex workers at high risk of infection.

Methods: CVS were collected from Kenyan HIV-seronegative (n = 34) and HIV-seropositive (n = 12) female sex workers, and were compared with those from HIV-seronegative low-risk women (n = 12).

Depot Medroxyprogesterone Acetate Use Is Associated With Elevated Innate Immune Effector Molecules in Cervicovaginal Secretions of HIV-1-Uninfected Women.

Objective: The effects of sex hormones on the immune defenses of the female genital mucosa and its susceptibility to infections are poorly understood. The injectable hormonal contraceptive depot medroxyprogesterone acetate (DMPA) may increase the risk for HIV-1 acquisition. We assessed the local concentration in the female genital mucosa of cationic polypeptides with reported antiviral activity in relation to DMPA use.

HIV acquisition is associated with increased antimicrobial peptides and reduced HIV neutralizing IgA in the foreskin prepuce of uncircumcised men.

Background: The foreskin is the site of most HIV acquisition in uncircumcised heterosexual men. Although HIV-exposed, seronegative (HESN) uncircumcised men demonstrate HIV-neutralizing IgA and increased antimicrobial peptides (AMPs) in the foreskin prepuce, no prospective studies have examined the mucosal immune correlates of HIV acquisition.

Methods: To assess the association of foreskin immune parameters with HIV acquisition, antimicrobial peptides and IgA with the capacity to neutralize a primary clade C HIV strain were quantified by blinded investigators, using sub-preputial swabs collected longitudinally during a randomized trial of male circumcision for HIV prevention in Rakai, Uganda.

Expression profiles of antimicrobial peptides in the genital tract of women using progesterone intrauterine devices versus combined oral contraceptives.

Problem: Sex hormones can influence the immune defenses of the female genital tract (FGT) and its susceptibility to infections. Here we investigated the effect of different hormonal contraceptives on the production of antimicrobial peptides (AMPs) in different compartments of the female genital mucosa (FGM), secretions and tissue.

Method Of Study: Cervicovaginal secretions (CVS) and ectocervical tissue samples obtained from women using progesterone intrauterine devices (pIUD) (n = 23) and combined oral contraceptives (COC) (n = 23) were analyzed for the expression and in situ localization of HNP1-3, BD-2, LL-37, SLPI and trappin-2 by ELISA, real-time PCR and immunohistochemistry.

Presence of CD8+ T cells in the ectocervical mucosa correlates with genital viral shedding in HIV-infected women despite a low prevalence of HIV RNA-expressing cells in the tissue.

The female genital tract is a portal of entry for sexual HIV transmission and a possible viral reservoir. In this study, the ectocervical CD8+ T cell distribution was explored in situ and was related to expression of CD3 and HLA-DR and presence of HIV RNA. For this purpose, ectocervical tissue samples and genital secretions were collected from HIV-seropositive (HIV+) Kenyan female sex workers (FSWs) (n = 20), HIV-seronegative (HIV-) FSWs (n = 17), and HIV(-) lower-risk women (n = 21).

HIV Infection in Uncircumcised Men Is Associated With Altered CD8 T-cell Function But Normal CD4 T-cell Numbers in the Foreskin.

Background: Human immunodeficiency virus (HIV)-infected (HIV+) men are more susceptible to sexually transmitted infections, and may be superinfected by HIV. We hypothesized that HIV induces immune alterations in the foreskin that may impact the subsequent acquisition/clearance of genital coinfections.

Methods: Foreskin tissue and blood were obtained from 70 HIV-uninfected and 20 HIV+ men undergoing circumcision.

Stable CD4 expression and local immune activation in the ectocervical mucosa of HIV-infected women.

Studies using genital tissue samples from HIV-infected women might provide important information about HIV susceptibility and transmission. In this study, ectocervical biopsies were obtained from 20 HIV-seropositive (HIV(+)) Kenyan female sex workers (FSW) and 20 HIV-seronegative lower risk (HIV(-) LR) women. To control for the impact of sex work, 20 HIV(-) FSW were also recruited.

Feasibility and safety of cervical biopsy sampling for mucosal immune studies in female sex workers from Nairobi, Kenya.

Background: There is an urgent need to improve our understanding of the mucosal immuno-pathogenesis of HIV acquisition in the female genital tract, particularly in high-risk women such as female sex workers (FSWs). Cervical biopsy samples offer technical advantages over cytobrush sampling, but there are concerns that this might increase HIV acquisition, particularly if healing is slow and/or women do not abstain from sex during healing.

Methodology/principal Findings: Cervical biopsy samples and cervico-vaginal swabs for co-infection diagnostics, prostate specific antigen (PSA) and immune studies were collected from 59 women, including HIV seropositive and HIV-exposed seronegative (HESN) FSWs as well as lower risk women from Nairobi, Kenya.

Cervicovaginal HIV-1-neutralizing immunoglobulin A detected among HIV-1-exposed seronegative female partners in HIV-1-discordant couples.

Objective: Cervicovaginal HIV-1-neutralizing immunoglobulin A (IgA) was associated with reduced HIV-1 acquisition in a cohort of commercial sex workers. We aimed to define the prevalence and correlates of HIV-1-neutralizing IgA from HIV-1-exposed seronegative (HESN) women in HIV-1-serodiscordant relationships.

Methods: HIV-1-serodiscordant couples in Nairobi were enrolled and followed quarterly up to 2 years, and women in concordant HIV-1-negative relationships were enrolled as controls.

A genetic polymorphism of FREM1 is associated with resistance against HIV infection in the Pumwani sex worker cohort.

A subgroup of women enrolled in the Pumwani sex worker cohort remain seronegative and PCR negative for human immunodeficiency virus type 1 despite repeated exposure through high-risk sex work. Studies have shown that polymorphisms of genes involved in antigen presentation and viral restriction factors are associated with resistance to HIV infection. To discover other possible genetic factors underlying this HIV-resistant phenotype, we conducted an exploratory nonbiased, low-resolution, genome-wide single-nucleotide polymorphism (SNP) analysis comparing 60 HIV-resistant women to 48 HIV-infected controls.

No difference in keratin thickness between inner and outer foreskins from elective male circumcisions in Rakai, Uganda.

It has been hypothesized that increased HIV acquisition in uncircumcised men may relate to a more thinly keratinized inner foreskin. However, published data are contradictory and potentially confounded by medical indications for circumcision. We tested the hypothesis that the inner foreskin was more thinly keratinized than the outer foreskin using tissues from 19 healthy, HIV-uninfected men undergoing routine prophylactic circumcision in Rakai, Uganda.

Impact of asymptomatic Herpes simplex virus-2 infection on T cell phenotype and function in the foreskin.

Herpes simplex virus type 2 (HSV-2) increases the risk of HIV acquisition in men and overall CD4 T cell density in the foreskin. Using tissues obtained during routine male circumcision, we examined the impact of HSV-2 on the function and phenotype of foreskin T cells in Ugandan men. HSV-2 infection was predominantly associated with a compartmentalized increase in CCR5 expression by foreskin CD4 T cells, which may contribute to HIV susceptibility.

HIV-neutralizing activity of cationic polypeptides in cervicovaginal secretions of women in HIV-serodiscordant relationships.

Background: HIV exposed seronegative (HESN) women represent the population most in need of a prophylactic antiviral strategy. Mucosal cationic polypeptides can potentially be regulated for this purpose and we here aimed to determine their endogenous expression and HIV neutralizing activity in genital secretions of women at risk of HIV infection.

Methodology/principal Findings: Cervicovaginal secretions (CVS) of Kenyan women in HIV-serodiscordant relationships (HESN, n = 164; HIV seropositive, n = 60) and low-risk controls (n = 72) were assessed for the cationic polypeptides HNP1-3, LL-37 and SLPI by ELISA and for HIV neutralizing activity by a PBMC-based assay using an HIV primary isolate.

In situ distribution of HIV-binding CCR5 and C-type lectin receptors in the human endocervical mucosa.

The endocervical mucosa is believed to be a primary site of HIV transmission. However, to date there is little known about the distribution of the HIV co-receptor CCR5 and the HIV-binding C-type lectin receptors, including Langerin, dendritic cell (DC)-specific intercellular adhesion molecule-grabbing non-integrin (DC-SIGN) and mannose receptor (MR) at this site. We therefore characterized the expression of these molecules in the endocervix of HIV seronegative women by computerized image analysis.

Detection of intraepithelial and stromal Langerin and CCR5 positive cells in the human endometrium: potential targets for HIV infection.

Both the upper (endocervix and uterus) and lower (ectocervix and vagina) female genital tract mucosa are considered to be target sites for sexual transmission of HIV. There are a few reports on the T cell and antigen-presenting cell distribution in human endometrial tissue however, there is little known about the expression of the HIV co-receptor CCR5 and HIV-binding C-type lectin receptors on endometrial cell subsets. We therefore assessed endometrial tissue sections from HIV seronegative women undergoing hysterectomy of a benign and non-inflammatory cause for phenotypic characterization of potential HIV target cells and receptors by immunohistochemistry.

Slumbering mucosal immune response in the cervix of human papillomavirus DNA-positive and -negative women.

Persistent human papillomavirus (HPV) infection is a prerequisite for cervical cancer and results from bypassing the local immune response. Twenty-four volunteers underwent an ectocervical biopsy, Pap smear, tests for sexually transmitted infections including HIV and HPV genotyping. All answered a questionnaire regarding medical history.

HIV-1 exposed uninfected men who have sex with men have increased levels of salivary CC-chemokines associated with sexual behavior.

Objectives: To determine whether soluble molecules with known anti-HIV-1 activity are increased in saliva of HIV-1 exposed uninfected individuals of discordant couples of men who have sex with men (MSM), and whether the levels of these molecules are associated with genetic polymorphisms, sexual behavior and/or HIV-1 neutralizing capacity.

Methods: Saliva and PBMC were collected from exposed uninfected individuals (n=25), and low-risk controls (n=22). Levels of CCL2, CCL3, CCL4, CCL5 and CCL11 were detected by Luminex, and SLPI, LL-37, alpha-defensins and IgA2 were detected by ELISA.

Abundant expression of HIV target cells and C-type lectin receptors in the foreskin tissue of young Kenyan men.

A biological explanation for the reduction in HIV-1 (HIV) acquisition after male circumcision may be that removal of the foreskin reduces the number of target cells for HIV. The expression of potential HIV target cells and C-type lectin receptors in foreskin tissue of men at risk of HIV infection were thus analyzed. Thirty-three foreskin tissue samples, stratified by Herpes simplex virus type 2 status, were obtained from a randomized, controlled trial conducted in Kenya.

Orally exposed uninfected individuals have systemic anti-HIV responses associating with partners' viral load.

Objectives: To determine whether oral HIV-1 exposure incites a persistent systemic anti-HIV-1 response in exposed uninfected individuals of discordant couples of men who have sex with men, and whether this response associates with HIV-1 exposure measured by viral load in the HIV-positive partners.

Methods: Plasma were collected from exposed uninfected individuals (n = 25), HIV-positive partners (n = 25) and low-risk controls (n = 22). A peripheral blood mononuclear cells-based neutralization assay was used to test these samples against three primary HIV-1 isolates.

Elevated elafin/trappin-2 in the female genital tract is associated with protection against HIV acquisition.

Objectives: Globally, heterosexual intercourse is the primary route of HIV-1 (HIV) transmission. It follows that mechanisms that protect against HIV infection are likely operative at the genital mucosa. In HIV-resistant Kenyan sex workers who are highly exposed to HIV infection yet remain uninfected, protection correlates with HIV-specific immune responses and genetic factors.

Abundant and superficial expression of C-type lectin receptors in ectocervix of women at risk of HIV infection.

Objectives: Dendritic cells (DCs) are among the first cells to encounter HIV after mucosal exposure and can bind virus via C-type lectin receptors (CLRs). Here, we characterized the distribution of various DC subtypes and the density of the CLRs, DC-SIGN, langerin, and mannose receptor in the ectocervix of HIV-seronegative women with low- and high-risk behavior for acquiring HIV.

Material And Methods: Cryosections from ectocervical biopsies, collected from sexually active low-risk healthy HIV immunoglobulin G-negative women (n = 10) and HIV immunoglobulin G-negative commercial sex workers (n = 8), were assessed by computerized image analysis.

Levels of innate immune factors in genital fluids: association of alpha defensins and LL-37 with genital infections and increased HIV acquisition.

Background: Several mucosal innate immune proteins exhibit HIV inhibitory activity and their analogues are potential microbicide candidates. However, their clinical associations and in-vivo role in cervicovaginal host defense against HIV acquisition are poorly defined.

Methods: Cervicovaginal secretions (CVSs) were collected from HIV uninfected Kenyan sex workers at enrolment into an HIV prevention trial.

Oral HIV-exposure elicits mucosal HIV-neutralizing antibodies in uninfected men who have sex with men.

Objective: To determine whether oral sexual exposure to HIV-1 (HIV) results in HIV-neutralizing activity in saliva of uninfected men who have sex with infected men?

Design: Saliva samples were collected from HIV IgG seronegative men (n = 25) whose male partners were HIV infected and from low-risk healthy controls (n = 22) and analyzed for HIV-neutralizing capacity.

Methods: The presence of neutralizing activity in saliva was tested in a peripheral blood mononuclear cell-based assay using primary HIV isolates. Self-reporting questionnaires described the individuals' sexual behaviors and routes of possible HIV exposure.