Regulation of innate and adaptive immunity by the female sex hormones oestradiol and progesterone

Sex hormones and autoimmunity

Autoimmune diseases occur more in women than in men, and this may be attributable to the role of estrogens. Androgens promote autoimmune diseases with a profile of type 1 cytokines, such as rheumatoid arthritis, whereas estrogens promote autoimmune diseases with a type 2 cytokine profile, like systemic lupus erythematosus. Both androgens and estrogens regulate the Th1/Th2 balance. Type 1 autoimmune diseases are improved when decrease type 1 cytokines (i.e. during fasting), or when there is a rise in type 2 cytokines (increased estrogens, as in pregnancy). Type 2 autoimmune diseases improve when type 2 cytokines are diminished (decreased estrogen, as in post-partum period) or when type 1 response is stimulated.

Temporomandibular joint bone tissue resorption in patients with early rheumatoid arthritis can be predicted by joint crepitus and plasma glutamate level

The aim was to investigate whether bone tissue resorption in early RA is related to crepitus of the temporomandibular joint (TMJ) and systemic levels of inflammatory mediators and markers and sex steroid hormones. Twentynine women and 18 men with recently diagnosed RA were examined for TMJ bone erosions with computerized tomography and TMJ crepitus was assessed. Blood samples were analyzed for glutamate, 5-HT, TNF, IL-1β, IL-6, VEGF, inflammatory markers, and estradiol, progesterone and testosterone. The TMJ erosion score was positively correlated to glutamate, and TMJ crepitus where crepitus, glutamate and ESR explained 40% of the variation in the bone erosion score. In the patients without crepitus, bone erosion score was positively correlated to glutamate, which was not the case in the patients with crepitus. In conclusion, the results of this study show that TMJ bone tissue resorption can be predicted by TMJ crepitus and glutamate in early RA.

Surface markers of lymphocyte activation in pregnant asthmatics

PROBLEM

Pregnancy-associated immunologic alterations may improve the course of asthma. Severe maternal asthma with an exacerbation impairs fetal growth.

METHOD OF STUDY

Lymphocyte activation was estimated by flow cytometry analysis of surface markers in non-pregnant healthy and mild or moderate persistent asthmatic women and healthy as well as mild or moderate persistent asthmatic, third trimester pregnant women.

RESULTS

Compared with non-pregnant healthy subjects (n = 12) activated pools within CD4 and CD8 T cells were larger and the number of NK T cells were increased both in non-pregnant asthmatic (n = 12) and in healthy pregnant (n = 13) subjects (all p\0.05). No further lymphocyte activation was observed in pregnant asthmatics (n = 21) compared either with non-pregnant asthmatic, or pregnant healthy women. Average birth weight of newborns was lower (p\0.05) in the asthmatic than in the healthy pregnant group.

CONCLUSION

Pregnancy is a state of wide-spread lymphocyte activation but it may blunt lymphocyte activation which characterizes bronchial asthma.

Sex hormone regulation of innate immunity in the female reproductive tract: the role of epithelial cells in balancing reproductive potential with protection against sexually transmitted pathogens

The immune system in the female reproductive tract (FRT) does not mount an attack against HIV or other sexually transmitted infections (STI) with a single endogenously produced microbicide or with a single arm of the immune system. Instead, the body deploys dozens of innate antimicrobials to the secretions of the female reproductive tract. Working together, these antimicrobials along with mucosal antibodies attack many different viral, bacterial and fungal targets. Within the FRT, the unique challenges of protection against sexually transmitted pathogens coupled with the need to sustain the development of an allogeneic fetus have evolved in such a way that sex hormones precisely regulate immune function to accomplish both tasks. The studies presented in this review demonstrate that estradiol and progesterone secreted during the menstrual cycle act both directly and indirectly on epithelial cells and other immune cells in the reproductive tract to modify immune function in a way that is unique to specific sites throughout the FRT. As presented in this review, studies from our laboratory and others demonstrate that the innate immune response is under hormonal control, varies with the stage of the menstrual cycle, and as such is suppressed at mid-cycle to optimize conditions for successful fertilization and pregnancy. In doing so, a window of STI vulnerability is created during which potential pathogens including HIV enter the reproductive tract to infect host targets.

Sex differences in the effects of maternal vitamin supplements on mortality and morbidity among children born to HIV-infected women in Tanzania

We examined whether there are sex differences in the effect of vitamin supplements on birth outcomes, mortality and morbidity by 2 years of age among children born to HIV-infected women in Tanzania. A randomised placebo-controlled trial was conducted among 959 mother-infant pairs. HIV-infected pregnant women were randomly assigned to receive a daily oral dose of one of four regimens: multivitamins (vitamins B-complex, C and E), vitamin A plus beta-carotene, multivitamins including vitamin A plus beta-carotene or placebo. Supplements were administered during pregnancy and continued after delivery. The beneficial effect of multivitamins on decreasing the risk of low birth weight was stronger among girls (relative risks (RR) = 0.39, 95 % CI 0.22, 0.67) than among boys (RR = 0.81, 95 % CI 0.44, 1.49; P for interaction = 0.08). Maternal multivitamin supplements resulted in 32 % reduction in mortality among girls (RR = 0.68, 95 % CI 0.47, 0.97), whereas no effect was found among boys (RR = 1.20, 95 % CI 0.80, 1.78; P for interaction = 0.04). Multivitamins had beneficial effects on the overall risks of diarrhoea that did not differ by sex. Vitamin A plus beta-carotene alone increased the risk of HIV transmission, but had no effects on mortality, and we found no sex differences in these effects. Sex differential effects of multivitamins on mortality may be due to sex-related differences in the immunological or genetic factors. More research is warranted to examine the effect of vitamins by sex and better understand biological mechanisms mediating such effects.

Chlamydia trachomatis, a hidden epidemic: effects on female reproduction and options for treatment

The number of genital tract Chlamydia trachomatis infections is steadily increasing worldwide, with approximately 50-70% of infections asymptomatic. There is currently no uniform screening practice, current antibiotic treatment has failed to prevent the increased incidence, and there is no vaccine available. We examined studies on the epidemiology of C. trachomatis infections, the effects infections have on the female reproductive tract and subsequent reproductive health and what measures are being taken to reduce these problems. Undetected or multiple infections in women can lead to the development of severe reproductive sequelae, including pelvic inflammatory disease and tubal infertility. There are two possible paradigms of chlamydial pathogenesis, the cellular and immunological paradigms. While many vaccine candidates are being extensively tested in animal models, they are still years from clinical trials. With no vaccine available and antibiotic treatment unable to halt the increased incidence, infection rates will continue to increase and cause a significant burden on health care systems.

Progesterone and 17beta-estradiol enhance regulatory responses to human papillomavirus type 16 virus-like particles in peripheral blood mononuclear cells from healthy women

Human papillomavirus (HPV) virus-like particle (VLP) vaccines are highly effective at preventing viral infections and the development of precancerous lesions through the induction of high-titer neutralizing antibodies and strong cell-mediated immune responses. Women taking combined oral contraceptives (COCs), however, show large variabilities in the magnitudes of their antibody responses. The goal of the present study was to determine the effects of 17beta-estradiol (E2) and progesterone (P4) alone and in combination on the cellular immune response to HPV type 16 (HPV-16) VLPs in vitro. Peripheral blood mononuclear cells (PBMCs) from healthy donor women were stimulated in vitro with HPV-16 VLPs (2.5 microg/ml) in the presence of E2 and P4 administered either alone or in combination; and lymphoproliferation, cytokine production, transcription factor expression, and steroid hormone receptor expression were analyzed. HPV-16 VLPs significantly increased the levels of lymphoproliferation, proinflammatory cytokine (gamma interferon [IFN-gamma], interleukin-1beta [IL-1beta], IL-2, IL-6, IL-8, IL-12p70, IL-17, tumor necrosis factor alpha [TNF-alpha]) production, anti-inflammatory cytokine (IL-1ra, IL-10) production, and the expression of Eralpha and Erbeta but decreased the levels of Foxp3 expression and production of transforming growth factor beta (TGF-beta). Exposure of PBMCs to E2 and P4 either alone or in combination significantly decreased the levels of lymphoproliferation and production of proinflammatory cytokines (IFN-gamma, IL-12p70, TNF-alpha) but increased the levels of production of IL-10 and TGF-beta and the expression of Foxp3 in response to HPV-16 VLPs. Treatment of cells with biologically relevant concentrations of sex steroid hormones suppressed the inflammatory response and enhanced the regulatory response to HPV-16 VLPs, which may have implications for predicting the long-term efficacy of HPV vaccines, adverse events, and cross-protection among women taking COCs.

Sex steroid hormones, hormonal contraception, and the immunobiology of human immunodeficiency virus-1 infection

Worldwide, an increasing number of women use oral or injectable hormonal contraceptives. However, inadequate information is available to aid women and health care professionals in weighing the potential risks of hormonal contraceptive use in individuals living with HIV-1 or at high risk of infection. Numerous epidemiological studies and challenge studies in a rhesus macaque model suggest that progesterone-based contraceptives increase the risk of HIV-1 infection in humans and simian immunodeficiency virus (SIV) infection in macaques, accelerate disease progression, and increase viral shedding in the genital tract. However, because several other studies in humans have not observed any effect of exogenously administered progesterone on HIV-1 acquisition and disease progression, the issue continues to be a topic of intense research and ongoing discussion. In contrast to progesterone, systemic or intravaginal treatment with estrogen efficiently protects female rhesus macaques against the transmission of SIV, likely by enhancing the natural protective properties of the lower genital tract mucosal tissue. Although the molecular and cellular mechanisms underlying the effect of sex steroid hormones on HIV-1 and SIV acquisition and disease progression are not well understood, progesterone and estrogen are known to regulate a number of immune mechanisms that may exert an effect on retroviral infection. This review summarizes current knowledge of the effects of various types of sex steroid hormones on immune processes involved in the biology of HIV-1 infection.

Progesterone in pregnancy; receptor-ligand interaction and signaling pathways

Progesterone is indispensable in creating a suitable endometrial environment for implantation, and also for the maintenance of pregnancy. Successful pregnancy depends on an appropriate maternal immune response to the fetus. Along with its endocrine effects, progesterone also acts as an "immunosteroid", by contributing to the establishment of a pregnancy protective immune milieu. Progesterone plays a role in uterine homing of NK cells and upregulates HLA-G gene expression, the ligand for NK inhibitory and activating receptors. At high concentrations, progesterone is a potent inducer of Th2-type cytokines as well as of LIF and M-CSF production by T cells. A protein called progesterone-induced blocking factor (PIBF), by inducing a Th2-dominant cytokine production mediates the immunological effects of progesterone. PIBF binds to a novel type of the IL-4 receptor and signals via the Jak/STAT pathway, to induce a number of genes, that not only affect the immune response, but might also play a role in trophoblast invasiveness.

Liposomal gD ectodomain (gD1-306) vaccine protects against HSV2 genital or rectal infection of female and male mice

Herpes simplex virus type 2 (HSV2) is the most common causative agent of genital herpes, with infection rates as high as 1 in 6 adults. The present studies were done to evaluate the efficacy of a liposomal HSV2 gD(1-306) vaccine (L-gD(1-306)-HD) in an acute murine HSV2 infection model of intravaginal (female) or intrarectal (male or female) challenge. Two doses of L-gD(1-306)-HD containing 60 microg gD(1-306)-HD and 15 microg monophosphoryl lipid A (MPL) per dose provided protection against HSV2 intravaginal challenge (86-100% survival, P< or =0.0003 vs. control liposomes; P=0.06 vs. L-gD(1-306)-HD without MPL). Both male and female mice (BALB/c and C57BL/6) immunized with L-gD(1-306)-HD/MPL were significantly protected against HSV2 intrarectal challenge, with higher survival rates compared to controls (71-100%, P< or =0.007). L-gD(1-306)-HD/MPL also provided increased survival when compared to a liposomal peptide vaccine, L-gD(264-285)-HD/MPL (male BALB/c, P</=0.001; female BALB/c and male C57BL/6, P=0.06). Mice given L-gD(1-306)-HD/MPL also had minimal disease signs, reduced viral burden in their spinal cords and elevated neutralizing antibody titers in the females. The vaccine also stimulated gD(1-306)-HD specific splenocytes of both male and female mice with significantly elevated levels of IFN-gamma compared to IL-4 (P< or =0.01) indicating that there was an enhanced Th1 response. These results provide the first evidence that the L-gD(1-306)-HD vaccine can protect both male and female mice against intrarectal HSV2 challenge.

The association between oral contraceptives, depot-medroxyprogesterone acetate, and trichomoniasis

BACKGROUND

Hormonal contraception use by women may increase the risk of acquiring certain sexually transmitted infections. We explored the effect of hormonal contraceptive use, specifically oral contraception (OC), and depot-medroxyprogesterone acetate (DMPA) on Trichomonas vaginalis infections in women.

METHODS

We examined data from a prospective case-control study of women with trichomoniasis and noninfected female patients recruited from 3 public sexually transmitted disease clinics. Women with positive wet mount microscopy or T. vaginalis culture results were classified as having trichomoniasis. Participants underwent physical examinations, sexually transmitted infections testing and completed questionnaires which included information about demographics, sexual behavior, douching and contraceptive use. We assessed the association between hormonal contraceptives and trichomoniasis using bivariable and multivariable analysis and estimated exposure odds ratios (ORs) and adjusted odds ratios (aORs) with 95% confidence intervals (CIs).

RESULTS

We identified 427 women with trichomoniasis and 144 uninfected women who had information reported about contraception use. Compared with nonhormonal contraceptive use, OC use was negatively associated with trichomoniasis in bivariable analysis (OR: 0.5; 95% CI: 0.3-0.8). This association was no longer statistically significant after adjusting for demographic variables, douching and condom use (aOR: 0.9; 95% CI: 0.5-1.6). Use of DMPA, compared with nonhormonal contraceptive use, was not associated with trichomoniasis in bivariable or multivariable analyses (OR: 1.0, 95% CI: 0.5-2.1; aOR = 1.4, 95% CI: 0.6-3.4, respectively).

CONCLUSIONS

Although OC use appeared to have a protective effect in the bivariable analysis, the hormonal contraceptives OC and DMPA were not associated with T. vaginalis infection after adjustment for other factors.

Impact of female sex hormones on the maturation and function of human dendritic cells

PROBLEM

During pregnancy, the immune and the endocrine system cooperate to ensure that the fetal allograft develops without eliciting a maternal immune response. This is presumably in part achieved by dendritic cells (DCs) that play a dominant role in maintaining peripheral tolerance. In this study, we investigated whether female sex hormones, such as human chorionic gonadotropin (hCG), progesterone (Prog), and estradiol (E2), which are highly elevated during pregnancy, induce the differentiation of DCs into a tolerance-inducing phenotype.

METHODS/RESULTS

Immature DCs were generated from blood-derived monocytes and differentiated in the presence of hCG, Prog, E2, or Dexamethasone (Dex) as a control. Unlike Dex, female sex hormones did not prevent the upregulation of surface markers characteristic for mature DCs, such as CD40, CD83, and CD86, except for hCG, which inhibited HLA-DR expression. Similarly, hCG, Prog, and E2 had any impact on neither the rearrangement of the F-actin cytoskeleton nor the enhanced chemokine secretion following DC maturation, both of which were strongly altered by Dex. Nevertheless, the T-cell stimulatory capacity of DCs was significantly reduced after hCG and E2 exposure.

CONCLUSION

Our findings suggest that the female sex hormones hCG and E2 inhibit the T-cell stimulatory capacity of DCs, which may help in preventing an allogenic T-cell response against the embryo.

Progesterone inhibits Toll-like receptor 4-mediated innate immune response in macrophages by suppressing NF-kappaB activation and enhancing SOCS1 expression

Although progesterone has been recognized as essential for the establishment and maintenance of pregnancy, this steroid hormone has been implicated to have a functional role in immune response, mainly at concentrations commensurate with pregnancy. However, the underlying mechanisms remain to be fully understood. Here we present the evidences that progesterone inhibited immune response to lipopolysaccharide (LPS) and CpG oligodeoxynucleotides (CpG ODNs) through modulating Toll-like receptor (TLR) signaling. Pretreatment with progesterone can significantly inhibit TLR4 and TLR9-triggered IL-6 and nitric oxide (NO) production in macrophages. Furthermore, we found that progesterone can significantly inhibit LPS-induced nitric oxide synthesis (iNOS), TLR4 expression and nuclear factor-kappaB (NF-kappaB) activation. Consistently, as a negative feedback inhibitor, the expression of suppressor of cytokine signaling (SOCS1) protein was up-regulated by progesterone in LPS-stimulated macrophages. These results support the concept that progesterone might inhibit innate immune response by suppressing NF-kappaB activation and enhancement of SOCS1 expression, providing a possible mechanistic explanation for the function of progesterone in regulating innate immune responses.

Regulation of dendritic cells by female sex steroids: Relevance to immunity and autoimmunity

Dendritic cells (DCs) are critical mediators of adaptive immunity, tolerance and autoimmunity. The human immune system exhibits sexual dimorphism, which is most evident in the female predominance of autoimmune diseases such as systemic lupus erythematosus (SLE). Female sex steroids are strongly implicated in mediating immune sexual dimorphism, in part because estrogen accentuates disease in several models of lupus autoimmunity. In contrast, progesterone may prevent disease development. While much investigation has focused on the effects of estrogen and progesterone on lymphocyte functions, far less attention has been paid to the effects of these hormones on DCs. Current evidence now indicates estrogen can activate DCs, while in contrast, progesterone inhibits DC functions. Thus, we hypothesize that the opposite effects these two hormones have on lupus autoimmunity reflect opposing effects on DC functions. Thus, through direct actions on DCs, female sex steroids may influence autoimmunity, immunity and tolerance.

Sex hormones and mucosal wound healing

Wound healing studies, which have chiefly examined dermal tissues, have reported a female advantage in healing rates. In contrast, our laboratory recently demonstrated women heal mucosal wounds more slowly than men. We hypothesized sex hormones influence wound healing rates, possibly through their modulating effects on inflammation. This study involved 329 younger subjects aged 18-43 (165 women, 164 men) and 93 older subjects aged 50-88 (60 women, 33 men). A 3.5mm diameter wound was created on the hard oral palate and videographed daily to assess wound closure. Blood collected at the time of wounding was used to assess circulating testosterone, progesterone and estradiol levels, and in vitro cytokine production in response to LPS. No strong associations were observed between healing times and estradiol or progesterone levels. However, in younger subjects, lower testosterone levels related to faster wound closure. Conversely, in older women higher testosterone levels related to (1) lower inflammatory responses; and (2) faster healing times. No such relationships were seen in older men, or in women taking oral contraceptives or hormone replacement therapy [HRT]. Older women (50-54 years) not yet experiencing menopause healed similarly to younger women and dissimilarly from age-matched post-menopausal women. This suggests that the deleterious effects of aging on wound healing occur secondary to the effects of menopause. Supporting this, there was evidence in post-menopausal women that HRT augmented wound closure. Overall, this study suggests that human mucosal healing rates are modulated by testosterone levels. Based upon when between-group differences were observed, testosterone may impact upon the proliferative phase of healing which involves immune processes such as re-epithelialization and angiogenesis.

Modulation of expression of Toll-like receptors in the human endometrium

PROBLEM

The purpose of the study was to investigate the different expressions of toll-like receptors (TLRs) in the proliferative and the secretory phase of endometrial tissue.

METHOD OF STUDY

Eight infertile women were included in this study. The endometrial tissues of proliferative and secretory phase were obtained from each woman. The tissues were evaluated for the expression of mRNA for TLR1-10 by reverse transcribed polymerase chain reaction (RT-PCR). The proteins of TLR2, 3, 4, and 9 were evaluated by Western blot. The mRNA and protein level of proliferative and secretory endometrial tissue from the same woman was compared. The data were analysed with SPSS15.0.

RESULTS

TLR1-7, 9, and 10 mRNA were expressed throughout the menstrual cycle, but in the same woman, the expression of TLR2-6, 9, and 10 mRNA was higher during the secretory phase than that in the proliferative phase. The Western blot also showed that the protein expression of TLR2, 3, 4, and 9 was stronger in the secretory phase than that in the proliferative phase in the same woman.

CONCLUSION

The expression of TLRs is cycle dependent in human endometrial tissue. The expressions of TLRs were higher in the secretory phase than that in the proliferative phase: this indicated that TLRs may be regulated by sex hormones throughout the menstrual cycle.

Experimental infection of human volunteers with Haemophilus ducreyi: fifteen years of clinical data and experience

Haemophilus ducreyi causes chancroid, which facilitates transmission of human immunodeficiency virus type 1. To better understand the biology of H. ducreyi, we developed a human inoculation model. In the present article, we describe clinical outcomes for 267 volunteers who were infected with H. ducreyi. There was a relationship between papule formation and estimated delivered dose. The outcome (either pustule formation or resolution) of infected sites for a given subject was not independent; the most important determinants of pustule formation were sex and host effects. When 41 subjects were infected a second time, their outcomes segregated toward their initial outcome, confirming the host effect. Subjects with pustules developed local symptoms that required withdrawal from the study after a mean of 8.6 days. There were 191 volunteers who had tissue biopsy performed, 173 of whom were available for follow-up analysis; 28 (16.2%) of these developed hypertrophic scars, but the model was otherwise safe. Mutant-parent trials confirmed key features in H. ducreyi pathogenesis, and the model has provided an opportunity to study differential human susceptibility to a bacterial infection.

Immunopathogenesis of pelvic endometriosis: role of hepatocyte growth factor, macrophages and ovarian steroids

Endometriosis, a chronic disease characterized by endometrial tissue located outside the uterine cavity is associated with chronic pelvic pain and infertility. However, an in-depth understanding of the pathophysiology of endometriosis is still elusive. It is generally believed that besides ovarian steroid hormones, the growth of endometriosis can be regulated by innate immune system in pelvic microenvironment by their interaction with endometrial cells and immune cells. We conducted a series of studies in perspectives of pelvic inflammation that is triggered primarily by bacterial endotoxin (lipopolysaccharide) and is mediated by toll-like receptor 4 and showed their involvement in the development of pelvic endometriosis. As a cellular component of innate immune system, macrophages were found to play a central role in inducing pelvic inflammatory reaction. We further report here that peritoneal macrophages retain receptors encoding for estrogen and progesterone and ovarian steroids also participate in producing an inflammatory response in pelvic cavity and are involved in the growth of endometriosis either alone or in combination with hepatocyte growth factor (HGF). As a pleiotropic growth factor, HGF retains multifunctional role ometriosis. We describe here the individual and step-wise role of HGF, macrophages and ovarian steroid hormones and their orchestrated involvement in the immunopathogenesis of pelvic endometriosis.

Estrogen inhibits dendritic cell maturation to RNA viruses

Dendritic cells (DCs) play a central role in initiating and polarizing the immune response. Therefore, DC maturation represents a key control point in the shift from innate to adaptive immunity. It is suspected that during pregnancy, hormones are critical factors that modulate changes reported to occur in maternal immunity. Here we examined the effect of 17-beta-estradiol (E2) on the maturational response triggered by virus in human DCs and its influence on their ability to activate naive T cells. We developed an in vitro system to measure the response of DCs to virus infection with Newcastle disease virus (NDV) after a 24-hour E2 treatment. Using this system, we demonstrated that E2 pretreatment down-regulated the antiviral response to RNA viruses in DCs by profoundly suppressing type I interferon (IFN) synthesis and other important inflammatory products. In addition, the DCs capacity to stimulate naive CD4 T cells was also reduced. These results suggest an important role for E2 in suppressing the antiviral response and provide a mechanism for the reduced immunity to virus infection observed during pregnancy.

Vulnerability of women in southern Africa to infection with HIV: biological determinants and priority health sector interventions

OBJECTIVE

To review biomedical determinants of women's vulnerability to infection with HIV and interventions to counter this, within the southern African context.

RESULTS

Apart from number of exposures, if any, several factors influence the efficiency of HIV transmission during sex. Acute HIV infection, with extraordinarily high semen viral load, in conjunction with concurrent partnerships maximizes this efficiency. Delaying sexual debut and avoiding HIV exposure among biologically and socially vulnerable youth is critical. Reducing unintended pregnancies keeps girls in school and prevents vertical (also possibly horizontal) transmission. Female condoms, especially newer versions, are an under-exploited prevention technology. Control of sexually transmitted infections (STI), which facilitate HIV acquisition and transmission, remains important, especially among the most at-risk populations. Pathogens, such as herpes simplex virus type 2, which contribute most to HIV transmission in southern Africa must be targeted, although the importance of bacterial vaginosis and Trichomonas vaginalis is under-recognized. Also, heavy episodic alcohol use affects sexual decision-making and condom skills. Moreover, prevailing social contexts, partly a consequence of poor leadership, constrain the behavioural 'choices' available for girls and women.

CONCLUSIONS

Priority health sector interventions for preventing HIV are: male and female condom programming; prevention and control of STI; outreach to most vulnerable populations; HIV testing in all patient-provider encounters; male circumcision; and the integration of HIV prevention within sexual and reproductive health services. Future interventions during acute HIV infection and microbicides will reduce women's biological vulnerability. Far-reaching measures, such as sexual equity and alcohol control, create conditions necessary for achieving sustained prevention results. These are, however, contingent on stronger, more informed cultural and political leadership.

Hormonal regulation of the humoral innate immune response in Drosophila melanogaster

Juvenile hormone (JH) and 20-hydroxy-ecdysone (20E) are highly versatile hormones, coordinating development, growth, reproduction and aging in insects. Pulses of 20E provide key signals for initiating developmental and physiological transitions, while JH promotes or inhibits these signals in a stage-specific manner. Previous evidence suggests that JH and 20E might modulate innate immunity, but whether and how these hormones interact to regulate the immune response remains unclear. Here we show that JH and 20E have antagonistic effects on the induction of antimicrobial peptide (AMP) genes in Drosophila melanogaster. 20E pretreatment of Schneider S2 cells promoted the robust induction of AMP genes, following immune stimulation. On the other hand, JH III, and its synthetic analogs (JHa) methoprene and pyriproxyfen, strongly interfered with this 20E-dependent immune potentiation, although these hormones did not inhibit other 20E-induced cellular changes. Similarly, in vivo analyses in adult flies confirmed that JH is a hormonal immuno-suppressor. RNA silencing of either partner of the ecdysone receptor heterodimer (EcR or Usp) in S2 cells prevented the 20E-induced immune potentiation. In contrast, silencing methoprene-tolerant (Met), a candidate JH receptor, did not impair immuno-suppression by JH III and JHa, indicating that in this context MET is not a necessary JH receptor. Our results suggest that 20E and JH play major roles in the regulation of gene expression in response to immune challenge.

Comparative studies on the interplay of testosterone, estrogen and progesterone in collagen induced arthritis in rats

Rheumatoid arthritis (RA) is a sexually dimorphic autoimmune disorder exhibiting a higher disease prevalence and severity among females. This study was carried out to understand the role of the major sex hormones viz., testosterone, estrogen and progesterone on the severity in arthritis. The interplay of the sex hormones was studied in a rat model of collagen induced arthritis (CIA). The parameters used for analyzing the disease severity included paw volume, radiology, histopathology of joint, markers for bone turnover, cytokine profile, levels of pain mediator (prostaglandin E(2)) and immune response to type II collagen. Arthritis induction to castrated and ovariectomised rats resulted in enhanced inflammation thereby indicating the importance of sex hormones. Treatment with physiological doses of dihydrotestosterone and estrogen attenuated the inflammation, with estrogen exhibiting higher potency. Progesterone was not shown to have any significance in disease modification; however, when progesterone was administered in combination with estrogen, the protective effects of estrogen were noticed to decrease.

Microenvironment of the feto–maternal interface protects the semiallogenic fetus through its immunomodulatory activity on dendritic cells

OBJECTIVE

To investigate the immunomodulatory activity of decidual culture supernatant on dendritic cell (DC) functions.

DESIGN

In vivo and in vitro experimental study using mice.

SETTING

Academic research laboratory.

ANIMAL(S)

C57BL/6-mated female Balb/c mice.

INTERVENTION(S)

Culture supernatants of decidual cells obtained from the uteri of allogenic pregnant mice (Balb/c x C57BL/6) were collected. Dendritic cells were purified from Balb/c mice spleens and pulsed with antigen during overnight culture. In some cultures, decidual supernatant was added at 5%, 10%, or 20% final concentration. Endometrial culture supernatant-treated DCs served as a control. Antigen-pulsed DCs were injected into the front footpads of syngeneic mice.

MAIN OUTCOME MEASURE(S)

Lymph nodes of primed mice were removed 5 days after DC injection. Antigen-specific proliferation and interleukin-10 and interferon gamma production by lymphocytes were measured by (3)H-Thymidine incorporation and ELISA, respectively.

RESULT(S)

The results showed that decidual culture supernatant markedly blocked in vivo antigen presentation by DCs and inhibited their capacity to induce interferon gamma (but not interleukin-10) production by primed lymphocytes.

CONCLUSION(S)

It seems that soluble factors produced by decidual cells are important mediators of immunoregulation at the feto-maternal interface, which provide the two fundamental requirements for protection of the semiallogenic fetus, namely immunologic tolerance and predominance of T helper 2 immunity, through modulation of DCs function.

Non-Hodgkin lymphoma in women: reproductive factors and exogenous hormone use

Few studies of reproductive hormone exposures and non-Hodgkin lymphoma (NHL) have examined NHL subtypes. Associations between reproductive hormonal factors and risk of all NHL and of two predominant subtypes, diffuse large-cell lymphoma (DLCL) (n = 233) and follicular lymphoma (n = 173), were investigated among women (n = 581) in a large, population-based, case-control study (1,591 cases, 2,515 controls). Controls (n = 836) identified by random digit dialing were frequency matched by age and county to incident NHL cases ascertained in the San Francisco Bay Area of California in 1988-1993. Adjusted unconditional logistic regression was used to obtain odds ratios. More than four pregnancies indicated a possible lower risk of all NHL (odds ratio (OR) = 0.81, 95% confidence interval (CI): 0.55, 1.2; p-trend = 0.06) and of DLCL (OR = 0.53, 95% CI: 0.31, 0.90; p-trend = 0.01). Exclusive use of menopausal hormone therapy for > or =5 years was associated with a reduced risk of all NHL (OR = 0.68, 95% CI: 0.48, 0.98) and of DLCL (OR = 0.50, 95% CI: 0.30, 0.85). Oral contraceptive use indicated a lower risk of all NHL (OR = 0.68, 95% CI: 0.49, 0.94), and perhaps DLCL (OR = 0.79, 95% CI: 0.51, 1.2), and of follicular lymphoma (OR = 0.75, 95% CI: 0.46, 1.2). Results suggest that endogenous and exogenous reproductive hormones confer different risks by NHL subtype and are associated with a reduced risk of DLCL in women.

Memory B cells in common variable immunodeficiency: clinical associations and sex differences

Common variable immunodeficiency (CVID) is a heterogeneous syndrome characterized by impaired antibody responses, recurrent infections, inflammatory, autoimmune and malignancy-related conditions. We evaluated the relationship between memory B cell phenotype, sex, age at diagnosis, immunologic and clinical conditions in 105 CVID subjects from one medical center. Reduced numbers of switched memory B cells (cutoff <or=0.55% of B cells) were an independent risk factor of granulomas, autoimmune diseases and splenomegaly (p<0.001). Not previously noted, CVID females had significantly more switched memory cells (p=0.007) than males. Splenectomized subjects did not have fewer IgM memory B cells and these numbers were not related to the development of lung disease, as previously proposed. Lower baseline serum IgG was an independent predictor of pneumonia (p=0.007) and severe infections (p=0.001). We conclude that outcomes in CVID depend on an interplay of factors including sex, numbers of switched memory B cells, and baseline serum IgG and IgA levels.

Estradiol selectively regulates innate immune function by polarized human uterine epithelial cells in culture

The goal of this study was to examine the role of E(2) in regulating innate immune protection by human uterine epithelial cells (UECs). Recognizing that UECs produce cytokines and chemokines to recruit and activate immune cells as well as viral and bacterial antimicrobials, we sought to examine the effect of E(2) on constitutive and Toll-like receptor (TLR) agonist (lipopolysaccharide (LPS) and poly (I:C))-induced immune responses. The secretion by polarized UECs in culture of interleukin (IL)-6, macrophage inhibitory factor (MIF), and secretory leukocyte protease inhibitor (SLPI) was examined as well as the mRNA expression of human beta-defensin-2 (HBD2), tumor necrosis factor (TNF)-alpha, IL-8, and nuclear factor (NF)-kB. When incubated with E(2) for 24-48 h, we found that E(2) stimulated UEC secretion of SLPI (fourfold) and mRNA expression of HBD2 (fivefold). Moreover, when antibacterial activity in UEC secretions was measured using Staphylococcus aureus, E(2) increased the secretion of soluble factor(s) with antibacterial activity. In contrast, E(2) had no effect on constitutive secretion of proinflammatory cytokines and chemokines by UECs but completely inhibited LPS- and poly (I:C)-induced secretion of MIF, IL-6, and IL-8. Estradiol also reversed the stimulatory effects of IL-1beta on mRNA expression of TNF-alpha, IL-8, and NF-kB by 85, 95, and 70%, respectively. As SLPI is known to inhibit NF-kB expression, these findings suggest that E(2) inhibition of proinflammatory cytokines may be mediated through SLPI regulation of NF-kB. Overall, these findings indicate that the production of cytokines, chemokines, and antimicrobials by UECs are differentially regulated by E(2). Further, it suggests that with E(2) regulation, epithelial cells that line the uterine cavity have evolved immunologically to be sensitive to viral and bacterial infections as well as the constraints of procreation.

Sexual dimorphism of humoral immunity with human vaccines

It has been contended that limited data exist on sex-difference in immune response with vaccines in humans. However, a comprehensive search of the literature retrieved 97 studies with 14 vaccines influenza (7 studies), hepatitis A (15 studies), hepatitis B (50 studies), pnuemococcal polysaccaride (4 studies), diphtheria (4 studies), rubella (3 studies), measles (2 studies), yellow fever (3 studies), meningococcal A (1 study), meningococcal C (1 study), tetanus (1 study), brucella (1 study), Venezuelan equine encephalitis (1 study) and rabies (4 studies), with sex-difference in humoral (antibody) response. These differences are associated with sex-difference in the clinical efficacy of influenza, hepatitis A, hepatitis B, pneumococcal polysaccharide and diphtheria vaccines and significant adverse reactions with rubella, measles and yellow fever vaccines. The genesis of these differences is uncertain but not entirely related to gonadal hormones (differences are seen in pre-pubertal and post-menopausal subjects not on hormone replacement therapy) or female sex (males had greater serological response for pneumococcal, diphtheria, yellow fever, Venezuelan equine encephalitis and in some studies with rabies vaccine. As sex-difference in humoral immune response was seen with most vaccines which cover the spectrum of mechanisms by which infectious agents cause disease (mucosal replication, viral viraemia, bacterial bacteraemia, toxin production and neuronal invasion), it is mandatory that vaccine trialists recruit a representative sample of females and males to be able to assess sex-differences which may have clinical implications.

Chronic hepatitis B virus (HBV) infection in pregnancy

BACKGROUND

Hepatitis B is a considerable disease burden among Asians. Little is known about its disease behaviour in pregnant women.

METHODS

Clinical, laboratory and radiological data of pregnant and peri-partum females with chronic hepatitis B virus (HBV) infection who were seen between years 1999 and 2004 were studied. Their progress was documented up to 6 months post-partum. This was compared with the age-matched and HBe status-matched, non-pregnant, female patients with chronic HBV infection, who were consecutively selected from the department's registry as controls (ratio 1 mother: 4 non-pregnant controls), over the corresponding period.

RESULTS

A total of 35 mothers and 140 controls were studied. Mean age of patients was 30.7 +/- 3.6 years. Majority of mothers (74.3%) presented during pregnancy itself. 1st:2nd:3rd trimester presentation = 20.0%:48.6%:5.7%. Majority (65.7%) were positive for HBe antigen (HBeAg) at the time of presentation. About 57.1% mothers had a clinical event in the form of alanine transferase (ALT) elevation and/or loss of HBeAg vs 28.8% among controls (P = 0.002). Among HBeAg-positive subjects, more mothers (14.3%) than controls (2.2%) had resultant HBeAg loss (P = 0.02). Among HBeAg negative subjects, more mothers than controls had serum ALT elevations in the post-partum period (P = 0.007). Overall, more mothers had elevated ALT levels than controls, regardless of their HBeAg status. Neither mothers nor control subjects decompensated clinically, neither required liver transplantation nor died during the study period.

CONCLUSIONS

Pregnancy is associated with serum ALT elevation and HBeAg loss in patients with chronic HBV infection in the peri-partum period.

Gender differences in skin: a review of the literature

BACKGROUND

There has been increasing interest in studying gender differences in skin to learn more about disease pathogenesis and to discover more effective treatments. Recent advances have been made in our understanding of these differences in skin histology, physiology, and immunology, and they have implications for diseases such as acne, eczema, alopecia, skin cancer, wound healing, and rheumatologic diseases with skin manifestations.

OBJECTIVE

This article reviews advances in our understanding of gender differences in skin.

METHODS

Using the PubMed database, broad searches for topics, with search terms such as gender differences in skin and sex differences in skin, as well as targeted searches for gender differences in specific dermatologic diseases, such as gender differences in melanoma, were performed. Additional articles were identified from cited references. Articles reporting gender differences in the following areas were reviewed: acne, skin cancer, wound healing, immunology, hair/alopecia, histology and skin physiology, disease-specific gender differences, and psychological responses to disease burden.

RESULTS

A recurring theme encountered in many of the articles reviewed referred to a delicate balance between normal and pathogenic conditions. This theme is highlighted by the complex interplay between estrogens and androgens in men and women, and how changes and adaptations with aging affect the disease process. Sex steroids modulate epidermal and dermal thickness as well as immune system function, and changes in these hormonal levels with aging and/or disease processes alter skin surface pH, quality of wound healing, and propensity to develop autoimmune disease, thereby significantly influencing potential for infection and other disease states. Gender differences in alopecia, acne, and skin cancers also distinguish hormonal interactions as a major target for which more research is needed to translate current findings to clinically significant diagnostic and therapeutic applications.

CONCLUSIONS

The published findings on gender differences in skin yielded many advances in our understanding of cancer, immunology, psychology, skin histology, and specific dermatologic diseases. These advances will enable us to learn more about disease pathogenesis, with the goal of offering better treatments. Although gender differences can help us to individually tailor clinical management of disease processes, it is important to remember that a patient's sex should not radically alter diagnostic or therapeutic efforts until clinically significant differences between males and females arise from these findings. Because many of the results reviewed did not originate from randomized controlled clinical trials, it is difficult to generalize the data to the general population. However, the pressing need for additional research in these areas becomes exceedingly clear, and there is already a strong foundation on which to base future investigations.

17beta-estradiol alters the activity of conventional and IFN-producing killer dendritic cells

Estrogens increase aspects of innate immunity and contribute to sex differences in the prevalence of autoimmune diseases and in response to infection. The goal of the present study was to assess whether exposure to 17beta-estradiol (E2) affects the development and function of bone marrow-derived dendritic cells and to determine whether similar changes are observed in CD11c(+) splenocytes exposed to E2 in vivo. E2 facilitated the differentiation of BM precursor cells into functional CD11c(+)CD11b(+)MHC class II(+) dendritic cells (DCs) with increased expression of the costimulatory molecules CD40 and CD86. Exposure of bone marrow-derived dendritic cells to E2 also enhanced production of IL-12 in response to the TLR ligands, CpG and LPS. In contrast, CD11c(+) cells isolated from the spleens of female C57BL/6 mice that were intact, ovariectomized, or ovariectomized with E2 replacement exhibited no differences in the number or activity of CD11c(+)CD11b(+)MHC class II(+) DCs. The presence of E2 in vivo, however, increased the number of CD11c(+)CD49b(+)NK1.1(low) cells and reduced numbers of CD11c(+)CD49b(+)NK1.1(high) cells, a surface phenotype for IFN-producing killer DCs (IKDCs). Ultrastructural analysis demonstrated that CD11c(+)NK1.1(+) populations were comprised of cells that had the appearance of both DCs and IKDCs. CD11c(+) splenocytes isolated from animals with supplemental E2 produced more IFN-gamma in response to IL-12 and IL-18. These data illustrate that E2 has differential effects on the development and function of DCs and IKDCs and provide evidence that E2 may strengthen innate immunity by enhancing IFN-gamma production by CD11c(+) cells.

Influence of reproductive activity, sex steroids, and seasonality on epigonal organ cellular proliferation in the skate (Leucoraja erinacea)

In elasmobranchs, the epigonal organ, a unique leukopoietic immune tissue, is associated with the gonads. As the ovaries increase in size during reproductive activity, the overall mass of the epigonal organ does not change. However, immunohistochemistry (proliferating cell nuclear antigen Ab) demonstrated more proliferative activity and extravasation of epigonal leukocytes from blood vessels in reproductively active (RA) skates (Leucoraja erinacea) than in non-reproductively active (NRA) skates. In addition, [(3)H]thymidine incorporation was greater in epigonal leukocytes from RA skates than in leukocytes from NRA skates. Plasma from RA skates, but not from NRA skates, increased proliferation of epigonal leukocytes in vitro, an effect that was not seen using steroid-free plasma. In contrast to the stimulatory effect of plasma on leukocyte proliferation, addition of steroids (estrogen, progesterone, testosterone, and dexamethasone) in vitro decreased [(3)H]thymidine incorporation. While the inhibitory response to steroids was seasonally variable, (3)[H]thymidine incorporation was always highest in RA animals, in which plasma steroid levels were also consistently highest. These studies suggest functional interactions between reproductive and immune tissues in the skate, and that cellular turnover in epigonal tissue may be influenced by gonadal activity.

Mortality associated with HIV-1, HIV-2, and HTLV-I single and dual infections in a middle-aged and older population in Guinea-Bissau

BACKGROUND

In Guinea-Bissau HIV-1, HIV-2, and HTLV-I are prevalent in the general population. The natural history of HIV/HTLV-I single and dual infections has not been fully elucidated in this population. Previous studies have shown that combinations of these infections are more common in older women than in men. The present study compares mortality associated with HIV-1, HIV-2, and HTLV-I single and dual infections in individuals over 35 years of age within an urban community-based cohort in Guinea-Bissau.

RESULTS

A total of 2,839 and 1,075 individuals were included in the HIV and HTLV-I mortality analyses respectively. Compared with HIV-negative individuals, adjusted mortality rate ratios (MRRs) were 4.9 (95% confidence interval (CI): 2.3, 10.4) for HIV-1, 1.8 (95%CI: 1.5, 2.3) for HIV-2, and 5.9 (2.4, 14.3) for HIV-1/HIV-2 dual infections. MRR for HTLV-I-positive compared with HTLV-I-negative individuals was 1.7 (1.1, 2.7). Excluding all HIV-positive individuals from the analysis, the HTLV-I MRR was 2.3 (1.3, 3.8). The MRR of HTLV-I/HIV-2 dually infected individuals was 1.7 (0.7, 4.3), compared with HIV/HTLV-I-negative individuals. No statistically significant differences were found in retrovirus-associated mortality between men and women.

CONCLUSION

HIV-1-associated excess mortality was low compared with community studies from other parts of Africa, presumably because this population was older and the introduction of HIV-1 into the community recent. HIV-2 and HTLV-I-associated mortality was 2-fold higher than the mortality in uninfected individuals. We found no significant differences between the mortality risk for HIV-2 and HTLV-I single infection, respectively, and HIV-2/HTLV-I dual infection. The higher prevalence of retroviral dual infections in older women is not explained by differential retrovirus-associated mortality for men and women.

Modulation of 17beta-estradiol on the number and cytotoxicity of NK cells in vivo related to MCM and activating receptors

Natural killer (NK) cells are key components of immune systems and their activities could be regulated by sex hormones. In the present study we investigate the effects of estrogen on the number and cytotoxic activity of NK cells in vivo. The number and cytotoxicity of NK cells in four groups (control, sham+vehicle, Ovx+vehicle and Ovx+E2) were determined. The results showed that 17beta-estradiol (E2) increased the number of NK cells, but reduced their cytotoxicity. The increase of NK cells proportions by E2 may be mediated by up-regulating the expression of MCM7 and MCM10 proteins, which are required for DNA replication licensing in cell proliferation. The suppressed cytotoxicity of splenic NK cells by E2 may be attributable to the down-regulation of NK cells activating receptors-CD69, NKp46, NKG2DL and 2B4 (CD244), which directly inhibited NK cell activation, resulting in the reduced secretion of the soluble factors-granzyme B and FasL. INF-gamma might also act as a negative regulator in the low cytotoxicity of NK cells. In addition, the number of the NK cells is not parallel to their cytotoxicity with a long-term exposure to E2 in vivo. These results suggest that E2-mediated low cytotoxicity of NK cells may regulate host immune response in pregnancy and some female predominant diseases.

Cytokine imbalance in the pathophysiology of major depressive disorder

OBJECTIVE

A substantial body of evidence indicates that dysregulation of the immune system is associated with Major Depressive Disorder (MDD). Because most cytokines have pleiotropic effects, we measured various subsets of cytokines to examine the association between immune response and MDD.

METHODS

Forty-eight hospitalized MDD patients and 63 normal controls were recruited. We measured in vitro monocytic (IL-6 and tumor necrosis factor (TNF)-alpha), Th1 (interferon (IFN)-gamma and interleukin (IL)-2), Th2 (IL-4), and Treg (transforming growth factor (TGF)-beta1) cytokine production as well as IL-2/IL-4 and IFN-gamma/IL-4 ratios for both groups. Depressive symptoms were assessed by Hamilton Depression Rating Scale. Patients were evaluated before and after 6 weeks of antidepressant treatment.

RESULTS

At admission, IL-6, TNF-alpha, TGF-beta1 production, and IFN-gamma/IL-4 ratio were significantly higher, whereas IFN-gamma, IL-2, and IL-4 were significantly lower in MDD patients. After treatment, IL-6 and TGF-beta1 production were significantly lower than before treatment.

CONCLUSION

We suggest that activation of monocytic proinflammatory cytokines, and inhibition of both Th1 and Th2 cytokines may be associated with immunological dysregulation in MDD. TGF-beta1 may be associated with the regulation of monocytic cytokines as well as Th1 and Th2 cytokines in MDD.

In vivo effects of bisphenol A in laboratory rodent studies

Concern is mounting regarding the human health and environmental effects of bisphenol A (BPA), a high-production-volume chemical used in synthesis of plastics. We have reviewed the growing literature on effects of low doses of BPA, below 50 mg/(kg day), in laboratory exposures with mammalian model organisms. Many, but not all, effects of BPA are similar to effects seen in response to the model estrogens diethylstilbestrol and ethinylestradiol. For most effects, the potency of BPA is approximately 10-1000-fold less than that of diethylstilbestrol or ethinylestradiol. Based on our review of the literature, a consensus was reached regarding our level of confidence that particular outcomes occur in response to low dose BPA exposure. We are confident that adult exposure to BPA affects the male reproductive tract, and that long lasting, organizational effects in response to developmental exposure to BPA occur in the brain, the male reproductive system, and metabolic processes. We consider it likely, but requiring further confirmation, that adult exposure to BPA affects the brain, the female reproductive system, and the immune system, and that developmental effects occur in the female reproductive system.

Attenuated fever in rats during late pregnancy is linked to suppressed interleukin-6 production after localized inflammation with turpentine

An attenuated fever response to pathogens during late pregnancy is a phenomenon that has been described in several mammalian species, and although mechanisms are not completely understood, decreased prostaglandin E2 (PGE2) synthesis has been implicated. Upstream of PGE2, there is evidence to suggest that anti-inflammatory cytokines such as interleukin-1 receptor antagonist (IL-1ra) could play a significant role. In the present study we addressed the role of pro-inflammatory cytokines during late pregnancy, specifically interleukin-6 (IL-6), an important circulating mediator in fever. Turpentine oil (TURP), a very potent pyrogen and activator of IL-6, was injected into the hind-limb muscle of rats at the 18th day of pregnancy (GD 18) or in non-pregnant (NP) age-matched female controls. As expected, TURP injection induced a highly significant fever in the NP animals, which peaked 11 h post-injection and lasted for over 24 h. This was accompanied by a significant rise in circulating IL-6 levels, which correlated with changes in PGE2 synthesizing enzymes expression in the hypothalamus. In complete contrast, TURP-induced fever was totally absent in GD 18 animals whose body temperature did not deviate from basal values. The lack of response was additionally reflected by the absence of change in IL-6 concentration and by the significant attenuation of PGE2 synthesizing enzymes expression, which correlated with the suppressed expression of SOCS3, a hypothalamic marker of IL-6 activity. Contrary to the changes in circulating IL-6 levels at GD 18, IL-1ra was induced to levels comparable to those of NP females, suggesting that the influence of this anti-inflammatory cytokine on the fever response to TURP is at best minimal. These data further confirm the importance of IL-6 in fever generation and provide evidence that it may be a key component of the attenuated fever response in late pregnancy.

Pregnancy and the risk of HIV-1 acquisition among women in Uganda and Zimbabwe

OBJECTIVE

Several studies have suggested that pregnancy is associated with an increased risk of HIV-1 acquisition. We used data from a large, prospective study of hormonal contraception and HIV-1 to evaluate the effect of pregnancy on the risk of HIV-1 acquisition.

DESIGN

A multicenter prospective cohort study.

METHODS

We examined 4439 women from family planning sites in Uganda and Zimbabwe contributing 31 369 follow-up visits during 1999-2004. Participants were aged 18-35 years, and had received pregnancy and HIV-1 testing quarterly for 15-24 months. Using proportional hazards modeling, we compared the time to HIV-1 acquisition among four groups: pregnant women, non-pregnant lactating (NP/L) women, and women neither pregnant nor lactating (NP/NL) who were either using or not using hormonal contraception.

RESULTS

A total of 211 participants became HIV-1 infected (2.7 per 100 woman-years; wy), including 13 pregnant women (1.6 per 100 wy), 33 NP/L women (2.7 per 100 wy), 126 NP/NL women using hormonal contraception (2.9 per 100 wy), and 39 NP/NL women not using hormonal contraception (2.7 per 100 wy). In multivariable analysis adjusting for site, age, living with partner, risky sexual behaviors, and incident vaginal, cervical and herpes simplex virus 2 infections, neither pregnant, NP/L, nor NP/NL women using hormonal contraception were at an increased risk of HIV-1 acquisition compared with NP/NL women not using hormonal contraception.

CONCLUSION

Neither pregnancy nor lactation placed women at increased risk of HIV-1 acquisition in this multisite, prospective study of African women. This information is important in planning interventions to reduce HIV-1 acquisition among women.

Progesterone reduces the migration of mast cells toward the chemokine stromal cell-derived factor-1/CXCL12 with an accompanying decrease in CXCR4 receptors

Mast cell recruitment is implicated in many physiological functions and several diseases. It depends on microenvironmental factors, including hormones. We have investigated the effect of progesterone on the migration of HMC-1(560) mast cells toward CXCL12, a chemokine that controls the migration of mast cells into tissues. HMC-1(560) mast cells were incubated with 1 nM to 1 microM progesterone for 24 h. Controls were run without progesterone. Cell migration toward CXCL12 was monitored with an in vitro assay, and statistical analysis of repeated experiments revealed that progesterone significantly reduced cell migration without increasing the number of apoptotic cells (P = 0.0084, n = 7). Differences between progesterone-treated and untreated cells were significant at 1 microM (P < 0.01, n = 7). Cells incubated with 1 microM progesterone showed no rearrangment of actin filaments in response to CXCL12. Progesterone also reduced the calcium response to CXCL12 and Akt phosphorylation. Cells incubated with progesterone had one-half the control concentrations of CXCR4 (mRNA, total protein, and membrane-bound protein). Progesterone also inhibited the migration of HMC-1(560) cells transfected with hPR-B-pSG5 plasmid, which contained 2.5 times as much PR-B as the control. These transfected cells responded differently (P < 0.05, n = 5) from untreated cells to 1 nM progesterone. We conclude that progesterone reduces mast cell migration toward CXCL12 and that CXCR4 may be a progesterone target in mast cells.

Recurrent pregnancy loss and inappropriate local immune response to sex hormones

PROBLEM

The cause of recurrent miscarriage is often unknown. Recurrent miscarriage may be associated with inappropriate responses to progesterone and estrogen. We examined whether the condition may be diagnosed by skin testing.

METHOD OF STUDY

In a longitudinal prospective study, the weal and flare reaction after intradermal injection of estradiol and progesterone was compared in 29 women with recurrent miscarriage to the response in 10 healthy women. Reactions were evaluated after 20 min, 24, and 48 hr and 5 days later.

RESULTS

Estrogen hypersensitivity was found in 23 patients, and progesterone hypersensitivity in 20 patients. No patient in the control group demonstrated sex hormone hypersensitivity.

CONCLUSION

Recurrent pregnancy loss may be associated with inappropriate local immune responses to sex hormones. Further research is necessary into the mechanisms of hypersensitivity to estrogen and progesterone and their interactions with other systems.

Induction of maternal tolerance to fetal alloantigens by RANTES production

PROBLEM

Previous studies have demonstrated a requirement for RANTES (regulated on activated normal T-cell expressed, and secreted) at immune privileged sites; we have investigated the role of RANTES in the induction of maternal-fetal tolerance.

METHOD OF STUDY

Endometrial and peripheral T lymphocytes were obtained from women with recurrent pregnancy losses (RPLs) and fertile women. RANTES modulation by progesterone or paternal alloantigens was measured by enzyme-linked immunosorbent assay or flow cytometry analysis.

RESULTS

Progesterone significantly increased intracellular RANTES expression in CD4+ and CD8+ endometrial T cells. Moreover, alloreactive lymphocytes from RPL patients produced lower RANTES levels when compared with those from fertile women. At the local level, treatment with recombinant RANTES induced a decrease in CCR5 and CXCR4 messenger RNA that correlated with an increase in T-bet expression. RPL patients and normally fertile women express RANTES similarly, but differ in their patterns of RANTES receptor expression.

CONCLUSION

RANTES may be implicated in the local induction of a Th1-type response necessary for successful implantation. Altered response to RANTES stimulation among some RPL patients may be responsible for poor pregnancy outcomes.