Paria Mirmonsef

The effects of commensal bacteria on innate immune responses in the female genital tract.

Citation 
Mirmonsef P, Gilbert D, Zariffard MR, Hamaker BR, Kaur A, Landay AL, Spear GT. The effects of commensal bacteria on innate immune responses in the female genital tract. Am J Reprod Immunol 2011; 65: 190–195

The Role of Bacterial Vaginosis and Trichomonas in HIV Transmission Across The Female Genital Tract

Bacterial vaginosis (BV) and Trichomonas vaginalis (TV) infections are both very common and are associated with increased risk of sexual transmission of HIV. There are several mechanisms by which BV and TV could affect susceptibility including inducing pro-inflammatory cytokines and disrupting mucosal barrier function. This review highlights recent advances in our understanding of how these genital conditions lead to an increased risk of HIV infection in women.

Human α-amylase Present in Lower-Genital-Tract Mucosal Fluid Processes Glycogen to Support Vaginal Colonization by Lactobacillus

Lactobacillus colonization of the lower female genital tract provides protection from the acquisition of sexually transmitted diseases, including human immunodeficiency virus, and from adverse pregnancy outcomes. While glycogen in vaginal epithelium is thought to support Lactobacillus colonization in vivo, many Lactobacillus isolates cannot utilize glycogen in vitro. This study investigated how glycogen could be utilized by vaginal lactobacilli in the genital tract. Several Lactobacillus isolates were confirmed to not grow in glycogen, but did grow in glycogen-breakdown products, including maltose, maltotriose, maltopentaose, maltodextrins, and glycogen treated with salivary α-amylase. A temperature-dependent glycogen-degrading activity was detected in genital fluids that correlated with levels of α-amylase. Treatment of glycogen with genital fluids resulted in production of maltose, maltotriose, and maltotetraose, the major products of α-amylase digestion. These studies show that human α-amylase is present in the female lower genital tract and elucidates how epithelial glycogen can support Lactobacillus colonization in the genital tract.

Free Glycogen in Vaginal Fluids Is Associated with Lactobacillus Colonization and Low Vaginal pH

Objective Lactobacillus dominates the lower genital tract microbiota of many women, producing a low vaginal pH, and is important for healthy pregnancy outcomes and protection against several sexually transmitted pathogens. Yet, factors that promote Lactobacillus remain poorly understood. We hypothesized that the amount of free glycogen in the lumen of the lower genital tract is an important determinant of Lactobacillus colonization and a low vaginal pH. Methods Free glycogen in lavage samples was quantified. Pyrosequencing of the 16S rRNA gene was used to identify microbiota from 21 African American women collected over 8–11 years. Results Free glycogen levels varied greatly between women and even in the same woman. Samples with the highest free glycogen had a corresponding median genital pH that was significantly lower (pH 4.4) than those with low glycogen (pH 5.8; p<0.001). The fraction of the microbiota consisting of Lactobacillus was highest in samples with high glycogen versus those with low glycogen (median = 0.97 vs. 0.05, p<0.001). In multivariable analysis, having 1 vs. 0 male sexual partner in the past 6 months was negatively associated, while BMI ≥30 was positively associated with glycogen. High concentrations of glycogen corresponded to higher levels of L. crispatus and L. jensenii, but not L. iners. Conclusion These findings show that free glycogen in genital fluid is associated with a genital microbiota dominated by Lactobacillus, suggesting glycogen is important for maintaining genital health. Treatments aimed at increasing genital free glycogen might impact Lactobacillus colonization.

Short Chain Fatty Acids Induce Pro-Inflammatory Cytokine Production Alone And In Combination With Toll-like Receptor Ligands

Citation Mirmonsef P, Zariffard MR, Gilbert D, Makinde H, Landay, AL, Spear GT. Short‐chain fatty acids induce pro‐inflammatory cytokine production alone and in combination with Toll‐like receptor ligands. Am J Reprod Immunol 2012; 67: 391–400

Exploratory comparison of vaginal glycogen and Lactobacillus levels in premenopausal and postmenopausal women.

ObjectivePrevious studies have suggested that glycogen expression in the vaginal epithelium decreases during menopause, resulting in reduced levels of lactobacilli. However, free glycogen in genital fluids and its relationship with Lactobacillus levels have not been compared in premenopausal and postmenopausal women. MethodsEighty-two cervicovaginal lavage samples were collected at different phases of the menstrual cycle from 11 premenopausal (4 HIV-uninfected and 7 HIV-infected) and 12 postmenopausal (7 HIV-uninfected and 5 HIV-infected) women during a 1- to 3-month period. Free glycogen was quantified in genital fluids. Lactobacillus levels were quantified by real-time polymerase chain reaction. Estrogen and progesterone levels in blood were determined by enzyme-linked immunosorbent assay. ResultsFree glycogen was detected in both premenopausal and postmenopausal women. Across all samples, those from postmenopausal women had significantly lower levels of free glycogen than those from premenopausal women (median, 0.002 vs 0.065 &mgr;g/&mgr;L, respectively; P = 0.03). Lactobacillus levels correlated positively with free glycogen in both premenopausal (Spearman r = 0.68, P < 0.0001) and postmenopausal (r = 0.60, P < 0.002) women. Samples from premenopausal women had higher Lactobacillus levels and lower vaginal pH (median log, 8.1; median pH, 4) than those from postmenopausal women (median log, 7.1; median pH, 4.6), although these differences were not significant. HIV status had no significant effect on these relationships. ConclusionsFree glycogen is detected in both premenopausal and postmenopausal women and correlates with Lactobacillus in both groups. These results point to the complexity of the relationship between menopause and vaginal microbiota and indicate that more careful studies of the role of glycogen are warranted.

The Barrier to HIV Transmission Provided by Genital Tract Lactobacillus Colonization

While resistance to HIV transmission is due to multiple mechanisms such as the epithelium, a lower genital tract microbiota dominated by Lactobacillus appears to play an important role. This article reviews selected recent research on genital tract microbiota in women including how microbiota impacts HIV resistance and factors affecting Lactobacillus colonization.

Glycogen Levels in Undiluted Genital Fluid and Their Relationship to Vaginal pH, Estrogen, and Progesterone

Background Colonization of the female lower genital tract with Lactobacillus provides protection against STIs and adverse pregnancy outcomes. Growth of genital Lactobacillus is postulated to depend on epithelial cell-produced glycogen. However, the amount of cell-free glycogen in genital fluid available for utilization by Lactobacillus is not known. Methods Eighty-five genital fluid samples from 7 pre-menopausal women taken over 4–6 weeks were obtained using the Instead SoftCup® (EvoFem, Inc., San Diego, CA, USA) by consented donors. Cell-free glycogen and glucose in genital fluids and estrogen and progesterone in blood were quantified. Findings Glycogen ranged from 0.1–32 μg/μl. There were significant differences between women in glycogen over the observation period. There was a strong negative correlation between glycogen and vaginal pH (r = -0.542, p<0.0001). In multivariable analysis, free glycogen levels were significantly negatively associated with both vaginal pH and progesterone (p < 0.001 and p = 0.004, respectively). Estrogen, glucose, age, sexual intercourse 24 hours prior to visit, and days after the initial visit were not significantly associated with free glycogen levels. Conclusion Cell-free glycogen concentrations can be very high, up to 3% of genital fluid, and are strongly associated with acidic vaginal pH. However, the fluctuations in glycogen levels in individuals and differences between individuals do not appear to be associated with estrogen.

IL-22 levels are associated with trichomonas vaginalis infection in the lower genital tract

IL‐22 has important functions at mucosal surfaces, including the induction of antimicrobial peptides and maintenance of epithelium. However, IL‐22 has not been investigated in the genital tract during TV infection.

Differential CD4+ cell count increase and CD4+ : CD8+ ratio normalization with maraviroc compared with tenofovir.

Objective:Studies exploring the immunologic effects of maraviroc (MVC) have produced mixed results; hence, it remains unclear whether MVC has unique immunologic effects in comparison with other antiretroviral drugs. We sought to determine whether MVC has differential effects compared with tenofovir disoproxil fumarate (TDF) during initial antiretroviral therapy. Design:Prospective study in AIDS Clinical Trials Group A5303, a double-blind, placebo-controlled trial (N = 262) of MVC vs. TDF, each combined with boosted darunavir and emtricitabine. Methods:A total of 31 cellular and soluble biomarkers were assayed at weeks 0 and 48. Polychromatic flow cytometry was performed on cryopreserved peripheral blood mononuclear cells. Soluble markers were assayed in plasma using ELISA kits. Analyses were as treated. Results:Analyses included 230 participants (119 in MVC arm and 111 in TDF arm). Over 48 weeks of treatment, no significant differences were detected in declines in markers of inflammation and activation with MVC vs. TDF. A greater CD4+ T-cell count increase (median +234 vs. +188 cells/&mgr;l, P = 0.036), a smaller CD8+ T-cell count decrease (−6 vs. −109 cells/&mgr;l, P = 0.008), and a smaller CD4+ : CD8+ ratio increase (0.26 vs. 0.39, P = 0.003) occurred with MVC. Among participants with a baseline CD4+ : CD8+ ratio less than 1, a smaller proportion of MVC group normalized to a ratio greater than 1 at week 48 (15 and 36%, P < 0.001). Conclusion:MVC resulted in less improvement in the CD4+ : CD8+ ratio driven by greater increase in CD4+ cell count but smaller decline in CD8+ cell count. Changes in soluble or cellular biomarkers of inflammation and immune activation were not different between MVC and TDF.