Serum IL-1RA levels increase from follicular to luteal phase of the ovarian cycle: A pilot study on human female immune responses.

The immune responses exhibited by females are distinct from those of males. Females are known to generate, among others, higher levels of antibodies, greater interferon responses, and increased levels of inflammatory mediators in response to pathogens. Mounting evidence suggests that gonadal hormones play a key role in these differences. To better understand the effect of cycling hormones on the immune response, we sought to investigate the relationship between gonadal hormone fluctuations during the ovarian cycle and the levels of interleukin 1ß and IL-1RA, both in circulation and in PBMCs in response to TLR4 stimulation, in healthy premenopausal females. To do this we measured the gonadal hormones 17ß-estradiol, progesterone, and luteinizing hormone, and the cytokines IL-1ß and IL-1RA in nine cycling females at several time points throughout one complete cycle. We evaluated 35 follicular, 17 ovulatory, and 44 luteal time points in our cohort and found a clear increase in serum levels of anti-inflammatory IL-1RA in the luteal phase, as compared to the follicular phase, and a positive correlation between both 17ß-estradiol and progesterone and IL-RA. There was no difference in the serum levels of IL-1ß and no difference in IL-1 ß or IL-1RA produced in response to LPS by PBMCs isolated from different phases. Division of the cycle into sub-phases revealed an increase in the level of IL-1RA by ovulation that persisted through the luteal phase. These data suggest that significant changes in the immune response occur throughout the ovarian cycle in healthy females.

Endometrial immunocompetent cells in proliferative and secretory phase of normal menstrual cycle.

BACKGROUND: Menstruation was presented as a result of inflammatory process. The total and relative numbers of the endometrial immunocompetitive cells vary during the different phases of the menstrual cycle. The aim of this morphological study is to make a contribution to understanding different distribution of leukocyte types during proliferative and secretory phase of normal menstrual cycle. MATERIALS AND METHODS: The study included 40 women (20 in proliferative and 20 in secretory phase of the menstrual cycle). Exploratory curettage performed as preoperative preparation due to uterine myomas. Immunophenotyping was performed by immunoalkaline phosphatase (APAAP) using monoclonal antibodies: CD15, CD20, CD30, CD45RO, CD56, CD57 and CD68. The results were statistically analysed using SPSS 20.0 software. RESULTS: Natural killer (NK) cells are dominant during secretory, and CD45RO T lymphocytes are dominant during proliferative phase of the menstrual cycle. During the secretory phase of menstrual cycle, leukocytes make 30% of total endometrial cells. NK cells (CD56+ bright subpopulation), activated T lymphocytes, macrophages and B lymphocytes significantly increase in their number during the secretory phase of menstrual cycle. CONCLUSIONS: Significant changes in endometrial leukocyte populations during proliferative and secretory phase of the menstrual cycle are emphasized. Changes in dominance of different leukocyte subpopulations are determined by hormonal and microenvironmental changes in modulatory factors that have not yet been fully explained.

Changes in Functional Activity of Neutrophils and Monocytes Isolated from the Peripheral Blood of Women at Different Phases of the Menstrual Cycle.

We studied functional activity of neutrophilic granulocytes and monocytes isolated from the peripheral blood of women during the follicular and luteal phases of the menstrual cycle. It was shown that phagocytic activity of neutrophilic granulocytes increases, their intracellular oxygen-dependent bactericidal activity decreases, and the number of monocyte extracellular traps increases in women in the luteal phase of the menstrual cycle in comparison with the follicular phase.

Tissue distribution of some immune cells in bovine reproductive tract during follicular and luteal phase.

More recent studies indicate that immune cells which secrete their secretory products or cytokines play an important role in reproductive system. In our study, immune cell populations (CD8+ T lymphocytes, CD68+ macrophages, plasma cells, siderophages, eosinophils) and expression of major histocompatibility complex (MHC) class I and class II were examined in female reproductive tract during follicular (n = 13) and luteal phase (n = 10). Plasma cells and eosinophil granulocytes are present in few numbers in luminal epithelium, but abundant in longitudinal muscle layer of uterus, whereas siderophages are the dominant cell type in stroma. Moreover, MHC-I and -II+ cells are expressed by individual cells in organ layers, while CD8+ T cells and CD68+ macrophages are dominant in epithelium and muscle layer, respectively. In conclusion, we did not found significant changes in immune cells according to follicular and luteal phases, but localization and numbers in each organ have changed according to both organ and layers. These results indicate that these factors may play a crucial role not only to generate an immune response but also to have a role in regulation of physiological functions in female reproductive organs.

Inflammatory and endothelial markers during the menstrual cycle.

BACKGROUND: The menstrual cycle exhibits a pattern of repeated inflammatory activity. The present study aims to evaluate inflammatory and endothelial markers during the two phases of a menstrual cycle. METHODS: The study cohort consisted of 102 women with regular menstrual cycles. Inflammatory and endothelial markers (interleukin-6 [IL-6], pentraxin-3 [PTX-3], hs-C reactive protein [hs-CRP], sE-selectin, sP-selectin, intracellular and vascular cell adhesion molecules [ICAM-1 and VCAM-1] and cathepsins L, B and S) were measured during the early follicular and the late luteal phase of a normal menstrual cycle. RESULTS: Pentraxin-3 (PTX-3) and hs-CRP were significantly higher during the follicular phase compared to the luteal phase (p < 0.001 respectively p = 0.025). The other inflammatory and endothelial markers, with the exception of cathepsin B, were higher, albeit not significantly, during the follicular phase. CONCLUSIONS: Inflammatory activity, expressed mainly by members of the pentraxin family, is higher during the early follicular compared to the luteal phase. This could be associated to menstruation but the exact mechanisms behind this pattern are unclear and might involve the ovarian hormones or an effect on hepatocytes.

Comparison of Follicular and Luteal Phase Mucosal Markers of HIV Susceptibility in Healthy Women.

The purpose of this study was to evaluate differences in vaginal immune cell populations, vaginal tissue gene expression, antimicrobial activity of the cervicovaginal (CV) lavage (CVL), vaginal flora, and p24 antigen production from CV tissues after ex vivo human immunodeficiency virus (HIV) infection between follicular (FOL) and luteal (LUT) phases of the menstrual cycle. CV tissue biopsies, CV secretions, and blood samples were obtained as part of two longitudinal clinical trials of healthy women (CONRAD D11-119 and A12-124 studies). Participants (n = 39) were HIV-seronegative women not using exogenous hormone supplementation, with normal menstrual cycles, who were screened to exclude sexually transmitted and reproductive tract infections. Serum levels of estradiol and progesterone were significantly higher in the LUT versus the FOL phase of the menstrual cycle. Controlling for race, reported contraceptive use/sexual practices, and clinical trial, we found no differences in vaginal tissue immune cell populations and activation status, transcriptomes, inhibition of HIV, herpes simplex virus type 2 and Escherichia coli by the CVL, vaginal pH or Nugent score, or production of p24 antigen after ex vivo infection by HIV-1BaL between CV samples obtained in the FOL phase versus the LUT phase of the menstrual cycle. There were no significant correlations between serum estradiol and progesterone levels and CV endpoints. The hypothesis that the LUT phase of the menstrual cycle represents a more vulnerable stage for mucosal infection with HIV was not supported by data from samples obtained from the lower genital tract (ectocervix and vagina) from these two clinical trials.

Molecular Signatures of Immune Activation and Epithelial Barrier Remodeling Are Enhanced during the Luteal Phase of the Menstrual Cycle: Implications for HIV Susceptibility.

UNLABELLED: The variable infectivity and transmissibility of HIV/SHIV has been recently associated with the menstrual cycle, with particular susceptibility observed during the luteal phase in nonhuman primate models and ex vivo human explant cultures, but the mechanism is poorly understood. Here, we performed an unbiased, mass spectrometry-based proteomic analysis to better understand the mucosal immunological processes underpinning this observed susceptibility to HIV infection. Cervicovaginal lavage samples (n = 19) were collected, characterized as follicular or luteal phase using days since last menstrual period, and analyzed by tandem mass spectrometry. Biological insights from these data were gained using a spectrum of computational methods, including hierarchical clustering, pathway analysis, gene set enrichment analysis, and partial least-squares discriminant analysis with LASSO feature selection. Of the 384 proteins identified, 43 were differentially abundant between phases (P < 0.05, ≥2-fold change). Cell-cell adhesion proteins and antiproteases were reduced, and leukocyte recruitment (interleukin-8 pathway, P = 1.41E-5) and extravasation proteins (P = 5.62E-4) were elevated during the luteal phase. LASSO/PLSDA identified a minimal profile of 18 proteins that best distinguished the luteal phase. This profile included cytoskeletal elements and proteases known to be involved in cellular movement. Gene set enrichment analysis associated CD4(+) T cell and neutrophil gene set signatures with the luteal phase (P < 0.05). Taken together, our findings indicate a strong association between proteins involved in tissue remodeling and leukocyte infiltration with the luteal phase, which may represent potential hormone-associated mechanisms of increased susceptibility to HIV. IMPORTANCE: Recent studies have discovered an enhanced susceptibility to HIV infection during the progesterone-dominant luteal phase of the menstrual cycle. However, the mechanism responsible for this enhanced susceptibility has not yet been determined. Understanding the source of this vulnerability will be important for designing efficacious HIV prevention technologies for women. Furthermore, these findings may also be extrapolated to better understand the impact of exogenous hormone application, such as the use of hormonal contraceptives, on HIV acquisition risk. Hormonal contraceptives are the most widely used contraceptive method in sub-Saharan Africa, the most HIV-burdened area of the world. For this reason, research conducted to better understand how hormones impact host immunity and susceptibility factors important for HIV infection is a global health priority.

The success rate of pregnancy in IUI cycles following endometrial sampling. A randomized controlled study: endometrial sampling and pregnancy rates.

OBJECTIVE: The aim of this work was to compare the pregnancy rates during IUI cycles with or without endometrial sampling. STUDY DESIGN: A prospective, randomized study. PATIENTS AND METHODS: 150 patients were recruited. They were classified into three groups. Each comprised 50 patients. Group 1 was considered the control group and underwent IUI with no endometrial sampling. Group 2 underwent Tao Brush endometrial sampling on day 8-9 of the uterine cycle that preceded the stimulation cycle, and finally, Group 3 underwent Tao Brush endometrial sampling on day 8-9 of the same IUI cycle OUTCOME OF THE STUDY: A positive pregnancy test. RESULTS: Pregnancy percentages were 18, 38, and 36 % for group 1, group 2, and group 3, respectively. The paired t test was used to compare each two individual group means. The results show a highly significant value for the paired t test of the control group and group 2 of the patients (p = 0.001), as well as a highly significant results (p = 0.002) for the group 3 and the control group. No significant value was present between the group 2 and 3 of patients (p = 0.322). CONCLUSION: Endometrial sampling significantly increases pregnancy rates in IUI procedures when it is done in the proliferative phase of the IUI cycle, or the cycle prior to IUI, than pregnancy rates with IUI alone.

Toll-like receptor 4 expression in decidual cells and interstitial trophoblasts across human pregnancy.

PROBLEM: Toll-like receptor-4 (TLR-4) protects against Gram-negative bacteria expressed lipopolysaccharide and 'danger signals' from injured or dying cells. Although decidual cells (DCs) and interstitial trophoblasts (ITs) are in close contact, TLR-4 has been studied extensively only in ITs. METHOD OF STUDY: Formalin-fixed, paraffin-embedded serial sections of endometrium in follicular and luteal phases and deciduas from first and second trimester elective terminations and third trimester normal deliveries were immunostained for TLR-4, trophoblast-specific cytokeratin, and DC-specific vimentin. HSCORE assessed TLR-4 immunostaining in DCs versus ITs. RESULTS: TLR-4 HSCORES were significantly higher in: (i) first trimester DCs than luteal phase pre-decidual stromal cells; (ii) first and third versus second trimester DCs, but similar between third trimester deciduas parietalis and basalis; (iii) first versus second trimester ITs; (iv) DCs versus ITs across gestation. CONCLUSION: Higher TLR-4 in DCs than ITs suggests DCs as primary targets for Gram-negative bacteria and/or inflammation-related danger signals.

Menstrual cycle influences Toll-like receptor responses.

BACKGROUND: Toll-like receptors (TLRs) are pattern recognition receptors that play an important role as mediators of innate immunity. Human studies have shown changes in endometrial TLR expression during the menstrual cycle and during pregnancy. Our objective was to measure peripheral TLR activity over the course of the menstrual cycle. METHODS: We recruited 11 healthy females, and using ELISA we measured sex hormone levels and IL-1ß, IL-6, IL-8 and TNF-α following stimulation of whole blood with different TLR agonists during follicular, and early and late luteal phases of the menstrual cycle. RESULTS: During the follicular phase, we observed lower levels of IL-6 and TNF-α following stimulation with the TLR2 agonist HKLM when compared with the early luteal phase; lower levels of IL-1ß, IL-6 and TNF-α following stimulation with the TLR4 agonist LPS, and lower levels of IL-1ß and TNF-α following stimulation with the TLR5 agonist flagellin. Decreased IL-6 levels in the late compared to the early luteal phase were also observed following stimulation with the TLR5 agonist flagellin. Compared with the follicular phase, the late luteal phase of the cycle resulted in decreased levels of IL-1ß and TNF-α following stimulation with the TLR1/TLR2 agonist Pam3CSK and the TLR6/TLR2 agonist FSL1, as well as decreased levels of TNF-α following stimulation with the TLR8 agonist ssRNA40. There were no differences in cytokine release across the menstrual cycle following stimulation with the TLR3 agonist polyriboinosinic polyribocytidylic acid, or the TLR7 agonist Imiquimod. CONCLUSION: This study is the first to demonstrate that TLR responsivity in peripheral blood fluctuates throughout the menstrual cycle.

Up-regulation of lymphocytic growth hormone secretion during the luteal phase of cycle and early pregnancy.

Growth hormone (GH) has been shown to be produced and secreted by peripheral immune cells. Therefore, we studied the release of GH by lymphocytes, during various stages of pregnancy and estrous cycle in the cow. The effect of leptin on the lymphocytic GH release was also investigated. Estradiol-17ß and progesterone concentrations in plasma were measured in all animals to confirm their reproductive status. Growth hormone levels measured in cell cultures during early pregnancy (days 60-80) and during the luteal phase were greater (p ≤ 0.01) than levels during follicular phase or mid (days 100-160) and late (days 240-245) pregnancy. Leptin treatment stimulated (p ≤ 0.05) lymphocytic GH release during mid-pregnancy when the basal GH levels were low. Changes in lymphocytic GH release and elevation of lymphocytic GH secretion by leptin during pregnancy and the absence of such effects in estrous cycle may indicate that leptin modulation of lymphocytic GH plays a role in the regulation of immune response during pregnancy.

A physiological role for inducible FOXP3(+) Treg cells. Lessons from women with reproductive failure.

We have previously shown a decreased frequency and function of Tregs in women suffering from recurrent spontaneous abortions (RSA). In the current study, we first investigated the expression of FOXP3 after T-cell activation. We observed that expression of FOXP3 in activated PBMCs was already present above baseline before any cell division, indicating that it was induced in cells that were previously negative for this transcription factor. Because RSA women showed a more limited expansion of FOXP3-positive cells, we next assessed the role of IL-2 signaling through STAT5, which is known to be required for generation of inducible Tregs (iTregs). We demonstrated not only that TGF-beta and IL-2 were diminished but also that the IL-2-STAT-5 signaling axis was down regulated in RSA women. Finally, in addition to a limited FOXP3(+) cells expansion in vitro, iTregs from RSA women showed a strikingly lower suppressor activity.

Trappin-2/Elafin: a novel innate anti-human immunodeficiency virus-1 molecule of the human female reproductive tract.

Trappin-2/Elafin is a serine protease inhibitor that plays a major role as an anti-inflammatory mediator at mucosal surfaces. In addition, Trappin-2/Elafin has antibacterial activity against Gram-positive and Gram-negative bacterial and fungal pathogens. In this study we examined the production of Trappin-2/Elafin by epithelial cells from the human upper and lower female reproductive tract as well as its activity as an anti-human immunodeficiency virus (HIV)-1 molecule. We found that primary uterine, Fallopian tube, cervical and ectocervical epithelial cells produce Trappin-2/Elafin constitutively and that production of Trappin-2/Elafin is enhanced following stimulation with Poly(I:C), especially by the uterine cells. Given the presence of Trappin-2/Elafin in the reproductive tract, we tested the ability of recombinant Trappin-2/Elafin to inhibit HIV-1, an important sexually transmitted pathogen. We found that recombinant Trappin-2/Elafin was able to inhibit both T-cell-tropic X4/IIIB and macrophage-tropic R5/BaL HIV-1 in a dose-dependent manner. The inhibitory activity was observed when virus was incubated with Trappin-2/Elafin but not when Trappin-2/Elafin was added to cells either before infection or after infection. This suggests that the mechanism of inhibition is likely to be a direct interaction between HIV-1 and Trappin-2/Elafin. Additionally, we measured the levels of secreted Trappin-2/Elafin in cervico-vaginal lavages (CVL) from both HIV-positive and HIV-negative women and found that average levels of secreted Trappin-2/Elafin were higher in the CVL from HIV-negative women, although the values did not reach statistical significance. We also found that women at the secretory phase of the menstrual cycle produced more Trappin-2/Elafin in CVL relative to women at the proliferative phase of the menstrual cycle. Our data suggest that Trappin-2/Elafin might be an important endogenous microbicide of the female reproductive tract that is protective against HIV-1.

Changes in endometrial natural killer cell expression of CD94, CD158a and CD158b are associated with infertility.

PROBLEM: Cycle-dependent fluctuations in natural killer (NK) cell populations in endometrium and circulation may differ, contributing to unexplained infertility. METHOD OF STUDY: NK cell phenotypes were determined by flow cytometry in endometrial biopsies and matched blood samples. RESULTS: While circulating and endometrial T cell populations remained constant throughout the menstrual cycle in fertile and infertile women, circulating NK cells in infertile women increased during the secretory phase. However, increased expression of CD94, CD158b (secretory phase), and CD158a (proliferative phase) by endometrial NK cells from infertile women was observed. These changes were not reflected in the circulation. CONCLUSION: In infertile women, changes in circulating NK cell percentages are found exclusively during the secretory phase and not in endometrium; cycle-related changes in NK receptor expression are observed only in infertile endometrium. While having exciting implications for understanding NK cell function in fertility, our data emphasize the difficulty in attaching diagnostic or prognostic significance to NK cell analyses in individual patients.

Gender- and menstrual phase dependent regulation of inflammatory gene expression in response to aerobic exercise.

The immunological reaction to exercise has been investigated with increasing intensity in the last 10-20 years, with most human studies performed in male subjects. Recently, gender-specific aspects have received growing attention, but studies carefully monitoring the influence of gender including the menstrual cycle, are rare. Here, we report gene expression patterns in response to a run at 93% of the individual anaerobic threshold of 9 women with regular menstrual cycles and no use of oral contraceptives who ran both at day 10 (follicular phase, F) and at day 25 (luteal phase, L) of their cycle. 12 male subjects (M) served as controls. The mRNA was pooled group wise and processed on a gene expression microarray encompassing 789 genes, including major genes of the inflammatory and anti-inflammatory reaction. The differences of gene expression between time points to (before run) and t1 (after run) were analyzed. Females in L showed a higher extent of regulation than females in F or men. Among those genes which were up-regulated above 1.5 fold change (log2) pro-inflammatory genes were significantly enriched (p = 0.033, after Bonferroni correction) in L, while this was not the case in F or M. Conversely, women in L showed a strong trend towards downregulation of anti-inflammatory genes. Some prominent genes like IL6 (coding for interleukin-6), and IL1RN (also termed IL1RA, coding for interleukin-1 receptor antagonist) were clearly regulated in opposite directions in L as opposed to F and M. In conclusion, women in L showed a distinctly different pattern of gene regulation in response to exercise, compared with women in F or M. The overall direction of gene expression changes of women in L is clearly pro-inflammatory. This finding accentuates a need for careful consideration of the female cyclic phase when investigating women in exercise immunology studies. Our results may also have implications relevant to other forms of stress in females.

Expansion of CD4+CD25+and FOXP3+ regulatory T cells during the follicular phase of the menstrual cycle: implications for human reproduction.

Regulatory T cells (Tregs) are thought to affect the severity of various infectious and autoimmune diseases. The incidence of autoimmune disease is higher in fertile women than in men. Thus, we investigated whether Treg numbers were modulated during the menstrual cycle by sex hormones. In fertile nonpregnant women, we detected an expansion of CD4(+)CD25(+)FOXP3(+) Tregs in the late follicular phase of the menstrual cycle. This increase was tightly correlated with serum levels of estradiol and was followed by a dramatic decrease in Treg numbers at the luteal phase. Women who have had recurrent spontaneous abortions (RSA) showed similarly low numbers of Tregs at both the follicular and luteal phases, comparable to numbers we observed in postmenopausal women. In addition to decreased numbers, Tregs from women with RSA were also functionally deficient, as higher numbers were required to exert a similar magnitude of suppression to CD4(+)CD25(+)FOXP3(+) cells from fertile women. Consequently, reproductive failure might result from the inability of Tregs in women with RSA to expand during the preimplantatory phase combined with their lower functional capacity. Additionally, the modulation of Treg numbers we observed in fertile women suggests that the stage of the menstrual cycle should be taken into account when Treg numbers are investigated clinically.

[Peculiarities of immunocompetent cell distribution in the endometrium in the proliferation phase of the normal menstrual cycle].

Quantity and peculiarity of lymphocytes in the endometrium in the proliferation phase of the normal menstrual cycle have been studied. Operative material from 14 women of reproductive age with the diagnosis of carcinoma colli uterine have been investigated. Our investigations included morphometric studies of the character, quantity and localization of the lymphocytes. General quantity of immunocompetent cells were represented by CD3+ T lymphocytes which exist in all layers of the endometrium, among them predominant was the CD8+T lymphocyte subpopulation. CD20+ B lymphocytes in fact were missing in the epithelium, but in the other layers of the endometrium they were found in insignificant quantity.

Exercise during late-follicular menstrual phase: influence on immune parameters.

AIM: The purpose of this study was to examine whether training status and plasma hormones (estradiol--E2, progesterone--P, luteinizing hormone--LH, and follicle-stimulating hormone--FSH) have an effect on selected immune indexes during or following an acute bout of exercise. METHODS: Seven female triathletes (TRI) and 7 recreationally active (REC) females were randomly assigned to rest (RE) and exercise (EX) trials during the late-follicular menstrual phase (LF). The EX was 1 hour of cycling at 63.1+/-6% VO2peak (TRI) and 61+/-5.1% VO2peak (REC) and RE was 1 hour of sitting. Blood was drawn for both trials at baseline (0H), 1 hour (1H), and at 3 hours (3H). RESULTS: Positive correlations were found between E2 and CD19+ cells for both groups as well as P and CD8+ cells for the REC group. E2 increased during EX and returned to baseline at 3HEX for both groups, however, LH remained elevated at 3HEX for REC. There were significant exercise time effects for CD3+, CD4+, CD8+, and CD3- CD16+ CD56+ cells. The NCMC and 1:1 were elevated at 1HEX for both groups and returned to baseline by 3HEX. During RE, CD3- CD16+ CD56+ cell numbers for both groups and NCMC for REC remained elevated at 3HRE. CONCLUSIONS: E2 and P correlated with CD19+ and CD8+ cells, respectively. Although there were transient exercise-induced changes in immune indexes and E2 and LH, with LH remaining elevated at 3HEX for REC, both training groups elicited similar responses for plasma hormones, lymphocyte subpopulations, and NCMC.

Stress-induced versus preovulatory and pregnancy hormonal levels in modulating cytokine production following whole blood stimulation.

Estradiol, progesterone, prolactin and cortisol concentrations are substantially increased during pregnancy. Also, cortisol and prolactin levels are elevated during stress. In the present study, we exposed peripheral blood to estradiol, progesterone, prolactin and cortisol alone or in combination for 24 h before stimulation with T-dependent (phytohemagglutinin, PHA) and independent activators (lipopolysaccharide, LPS) to study their immunomodulatory role in interleukin-12 (IL-12), tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), and IL-10 production in a whole blood model. This should be similar to in vivo exposure conditions such as long-term stress, preovulatory or pregnancy periods. The present study showed that the stress-induced and preovulatory levels of prolactin and estradiol, respectively, increased the production of IFN-gamma and IL-12 levels (and IL-10 in the case of estradiol) in PHA + LPS-stimulated whole blood, and inhibited a hydrocortisone (100 nmol/l) suppressive effect on IFN-gamma, IL-12 and IL-10 productions. In LPS-stimulated whole blood, however, prolactin enhanced only IL-10 production levels in a non-concentration-dependent manner. Higher prolactin levels as in pregnancy did not modulate any of the cytokines, but pregnancy estradiol concentrations only induced higher IL-10 levels in PHA + LPS-stimulated whole blood. All progesterone levels tested revealed no effect on any of the cytokines following whole blood stimulation. Our results indicate that (1) a long exposure time of prolactin and estradiol to whole blood modulates the production of cytokines in a concentration- and stimulus-dependent manner; (2) stress-induced levels of prolactin and preovulatory estradiol concentrations can regulate cortisol-induced cytokine suppression, and (3) even though the cytokine pattern is different, pregnancy estradiol and cortisol levels decreased the IFN-gamma/IL-10 ratio, thereby keeping the anti-inflammatory IL-10 levels favored during pregnancy, which could be useful in regulating inflammatory-mediated autoimmune diseases.

Physiological changes of Fas expression in peripheral lymphocyte subsets during the menstrual cycle.

We have examined changes in peripheral lymphocyte subsets, and Fas expression in these subsets, during the menstrual cycle. Measurements were made by three-color flow cytometry in the follicular and luteal phases of the menstrual cycle in ten healthy women. The numbers of leukocytes, granulocytes and monocytes were significantly higher in the luteal phase than the follicular phase. The percentage of CD8(+) cells was greater in the luteal phase than the follicular phase. The percentages of Fas(+) cells among T cells and NK cells were higher in the luteal phase than the follicular phase. These findings suggest that the menstrual cycle affects leukocytes, lymphocyte subsets, and Fas expression in these subsets, and that changes in the luteal phase of the menstrual cycle are similar to those in pregnancy.