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Background: Adolescent girls and young women (AGYW) are at high risk of sexually transmitted infections (STIs). It is unknown whether beginning to have sexual intercourse results in changes to immune mediators in the cervicovaginal tract that contribute to this risk. Methods: We collected cervicovaginal lavages from Kenyan AGYW in the months before and after first penile-vaginal sexual intercourse and measured the concentrations of 20 immune mediators. We compared concentrations pre- and post-first sex using mixed effect models. We additionally performed a systematic review to identify similar studies and combined them with our results by meta-analysis of individual participant data. Results: We included 180 samples from 95 AGYW, with 44% providing only pre-first sex samples, 35% matched pre and post, and 21% only post. We consistently detected 19/20 immune mediators, all of which increased post-first sex (p

The selection of any specific immunization route is critical when defining future vaccine strategies against a genital infection like Chlamydia trachomatis (C.t.). An optimal Chlamydia vaccine needs to elicit mucosal immunity comprising both neutralizing IgA/ IgG antibodies and strong Th1/Th17 responses. A strategic tool to modulate this immune profile and mucosal localization of vaccine responses is to combine parenteral and mucosal immunizations routes. In this study, we investigate whether this strategy can be adapted into a two-visit strategy by simultaneous subcutaneous (SC) and nasal immunization. Using a subunit vaccine composed of C.t. antigens (Ags) adjuvanted with CAF01, a Th1/Th17 promoting adjuvant, we comparatively evaluated Ag-specific B and T cell responses and efficacy in mice following SC and simultaneous SC and nasal immunization (SIM). We found similar peripheral responses with regard to interferon gamma and IL-17 producing Ag-specific splenocytes and IgG serum levels in both vaccine strategies but in addition, the SIM protocol also led to Ag-specific IgA responses and increased B and CD4+ T cells in the lung parenchyma and in lower numbers also in the genital tract (GT). Following vaginal infection with C.t., we observed that SIM immunization gave rise to an early IgA response and IgA-secreting plasma cells in the GT in contrast to SC immunization, but we were not able to detect more rapid recruitment of mucosal T cells. Interestingly, although SIM vaccination in general improved mucosal immunity we observed no improved efficacy against genital infection compared to SC, a finding that warrants for further investigation. In conclusion, we demonstrate a novel vaccination strategy that combines systemic and mucosal immunity in a two-visit strategy. [ABSTRACT FROM AUTHOR]

Problem Pregnancy-mediated changes in immunity may influence risk of HIV-1 acquisition. This risk appears greatest among non- Caucasian women. Method of study Pregnant women with low risk of immune disruption were enrolled in a prospective observational cohort. Study visits occurred each trimester and postpartum. Semi-quantitative vaginal cultures and concentrations of cervical cytokines were compared between Caucasian and non- Caucasian women. Results In the second trimester, non- Caucasian women were more likely to be colonized with Gardnerella vaginalis (62% versus 25%, P = 0.02) and non-pigmented anaerobic gram-negative rods (43% versus 8%, P = 0.01). Mycoplasma hominis was more frequently isolated in non- Caucasian women throughout the second (29% versus 4%, P = 0.03) and third trimesters (35% versus 6%, P = 0.04). Non- Caucasian women had higher median interleukin ( IL)-10 concentrations throughout the second (128 pg/mL versus 7 pg/mL, P = 0.05) and third trimesters (224 pg/mL versus 7 pg/mL, P = 0.05). Conclusion Non- Caucasian women experienced a greater diversity of microorganisms and increased IL-10 in the second and third trimesters. [ABSTRACT FROM AUTHOR]

Clin Microbiol Infect 2012; 18 (Suppl. 5): 117-122 Abstract The female genital mucosa constitutes the major port of entry of sexually transmitted infections. Most genital microbial pathogens represent an enormous challenge for developing vaccines that can induce genital immunity that will prevent their transmission. It is now established that long-lasting protective immunity at mucosal surfaces has to involve local B-cell and T-cell effectors as well as local memory cells. Mucosal immunization constitutes an attractive way to generate systemic and genital B-cell and T-cell immune responses that can control early infection by sexually transmitted pathogens. Nevertheless, no mucosal vaccines against sexually transmitted infections are approved for human use. The mucosa-associated immune system is highly compartmentalized and the selection of any particular route or combinations of routes of immunization is critical when defining vaccine strategies against genital infections. Furthermore, mucosal surfaces are complex immunocompetent tissues that comprise antigen-presenting cells and also innate immune effectors and non-immune cells that can act as 'natural adjuvants' or negative immune modulators. The functions of these cells have to be taken into account when designing tissue-specific antigen-delivery systems and adjuvants. Here, we will discuss data that compare different mucosal routes of immunization to generate B-cell and T-cell responses in the genital tract, with a special emphasis on the newly described sublingual route of immunization. We will also summarize data on the understanding of the effector and induction mechanisms of genital immunity that may influence the development of vaccine strategies against genital infections. [ABSTRACT FROM AUTHOR]

Abstract: Genital herpes caused by herpes simplex virus type 2 (HSV-2) remains the leading cause of genital ulcers worldwide. Given the disappointing results of the recent genital herpes vaccine trials in humans, development of novel vaccine strategies capable of eliciting protective mucosal and systemic immune responses to HSV-2 is urgently required. Here we tested the ability of the adjuvant IC31® in combination with HSV-2 glycoprotein D (gD) used through intranasal (i.n.), intradermal (i.d.), or subcutaneous (s.c.) immunization routes for induction of protective immunity against genital herpes infection in C57BL/6 mice. Immunization with gD plus IC31® through all three routes of immunization developed elevated gD-specific serum antibody responses with HSV-2 neutralizing activity. Whereas the skin routes promoted the induction of a mixed IgG2c/IgG1 isotype profile, the i.n. route only elicited IgG1 antibodies. All immunization routes were able to induce gD-specific IgG antibody responses in the vaginas of mice immunized with IC31®-adjuvanted gD. Although specific lymphoproliferative responses were observed in splenocytes from mice of most groups vaccinated with IC31®-adjuvanted gD, only i.d. immunization resulted in a significant splenic IFN-γ response. Further, immunization with gD plus IC31® conferred 80–100% protection against an otherwise lethal vaginal HSV-2 challenge with amelioration of viral replication and disease severity in the vagina. These results warrant further exploration of IC31® for induction of protective immunity against genital herpes and other sexually transmitted infections. [Copyright &y& Elsevier]

Abstract: A vaccine against heterosexual transmission by human immunodeficiency virus (HIV) should generate cytotoxic and antibody responses in the female genital tract and in extra-genital organs. We report that sublingual immunization with HIV-1 gp41 and a reverse transcriptase polypeptide coupled to the cholera toxin B subunit (CTB) induced gp41-specific IgA antibodies and antibody-secreting cells, as well as reverse transcriptase-specific CD8 T cells in the genital mucosa, contrary to intradermal immunization. Conjugation of the reverse transcriptase peptide to CTB favored its cross-presentation by human dendritic cells to a T cell line from an HIV+ patient. Sublingual vaccination could represent a promising vaccine strategy against heterosexual transmission of HIV-1. [Copyright &y& Elsevier]

Background: Mucosal immunity of the female genital tract plays a critical role in defense against sexually transmitted infections like HIV. Pregnancy is associated with both structural and immunologic alterations in the genital mucosa, but the impact of these changes on its ability to suppress HIV infection is unknown. Current epidemiologic data are conflicting as to whether pregnancy increases the risk of HIV acquisition.Objective: The purpose of this study was to define the association between antimicrobial peptides and chemokines in cervicovaginal secretions and in vitro HIV infectivity among pregnant and nonpregnant women.Study Design: Forty pregnant and 37 nonpregnant women were enrolled in a prospective longitudinal cohort study at a single tertiary care women's hospital in Providence, RI. Cervicovaginal lavage was performed at each study visit. For pregnant women, study visits occurred once per trimester, and there was an optional postpartum visit. For nonpregnant women, study visits occurred across a single cycle that was timed to occur in the proliferative, ovulatory, and secretory phases based on the presumption of a regular menstrual cycle. The impact of cervicovaginal lavage on HIV infectivity was evaluated using a TZM-bl assay and compared between pregnant and nonpregnant women for each visit. The previously validated TZM-bl assay, which uses a luciferase reporting gene to indicate HIV infection of TZM-bl cells, was measured with a luminometer with higher relative light units that indicate greater levels of in vitro HIV infection. Immune mediators were measured with a multiplex bead assay. HIV infectivity and median concentration of each mediator were compared between pregnant and nonpregnant groups with the Wilcoxon rank sum test.Results: Cervicovaginal fluid from pregnant and nonpregnant women significantly decreased HIV infectivity in both groups compared with positive control (virus only; P<.01), but infectivity was not different between groups (P≥.44). During the second and third trimesters, pregnant women experienced suppression of several cervicovaginal immune mediators that included human beta defensin-2; lactoferrin; macrophage inflammatory protein-3α; regulated on activation, normally T-cell expressed and secreted; and stromal cell-derived factor-1 (all P≤.05). The antimicrobial peptide elafin was significantly correlated with HIV infectivity in both groups across all visits, except at the postpartum visit in the pregnant group (n=16). Secretory leukocyte protease inhibitor also was correlated significantly with infectivity across all visits, but in nonpregnant women only (P≤.03).Conclusion: Cervicovaginal secretions from both pregnant and nonpregnant women contain immune mediators that are associated with HIV infectivity in an in vitro assay; however, infectivity was not different between pregnant and nonpregnant groups. If pregnant women are at increased risk for HIV infection, it is unlikely to be mediated by alterations in the effectiveness of these protective secretions. [ABSTRACT FROM AUTHOR]