Pregnancy associated hormones modulate the cytokine production but not the phenotype of PBMC-derived human dendritic cells

Evaluation of the maternal systemic immune system during frozen euploid embryo transfer according to cycle outcome

Infertility affects 15 % of couples in the US, and many turn to assisted reproductive technologies, including in vitro fertilization and subsequent frozen embryo transfer (FET) to become pregnant. This study aimed to perform a broad assessment of the maternal immune system to determine if there are systemic differences on the day of FET in cycles that result in a live birth compared to those that do not. Women undergoing FET of euploid embryos were recruited and blood was collected on the day of FET as well as at early timepoints in pregnancy. Sixty immune and angiogenic proteins were measured in plasma, and gene expression of 92 immune-response related genes were evaluated in peripheral blood mononuclear cells (PBMCs). We found plasma concentrations of interleukin-13 (IL-13) and macrophage derived chemokine (MDC) were significantly lower on the day of FET in cycles that resulted in a live birth. We also found genes encoding C-C chemokine receptor type 5 (CCR5), CD8 subunit alpha (CD8A) and SMAD family member 3 (SMAD3) were upregulated in PBMCs on the day of FET in cycles that resulted in live birth. Measurements of immune mediators from maternal blood could serve as prognostic markers during FET to guide clinical decision making and further our understanding of implantation failure.

Dendritic Cells and the Establishment of Fetomaternal Tolerance for Successful Human Pregnancy

Pregnancy is a remarkable event where the semi-allogeneic fetus develops in the mother's uterus, despite genetic and immunological differences. The antigen handling and processing at the maternal-fetal interface during pregnancy appear to be crucial for the adaptation of the maternal immune system and for tolerance to the developing fetus and placenta. Maternal antigen-presenting cells (APCs), such as macrophages (Mφs) and dendritic cells (DCs), are present at the maternal-fetal interface throughout pregnancy and are believed to play a crucial role in this process. Despite numerous studies focusing on the significance of Mφs, there is limited knowledge regarding the contribution of DCs in fetomaternal tolerance during pregnancy, making it a relatively new and growing field of research. This review focuses on how the behavior of DCs at the maternal-fetal interface adapts to pregnancy's unique demands. Moreover, it discusses how DCs interact with other cells in the decidual leukocyte network to regulate uterine and placental homeostasis and the local maternal immune responses to the fetus. The review particularly examines the different cell lineages of DCs with specific surface markers, which have not been critically reviewed in previous publications. Additionally, it emphasizes the impact that even minor disruptions in DC functions can have on pregnancy-related complications and proposes further research into the potential therapeutic benefits of targeting DCs to manage these complications.

The effects of progesterone on immune cellular function at the maternal-fetal interface and in maternal circulation

Progesterone is a sex steroid hormone that plays a critical role in the establishment and maintenance of pregnancy. This hormone drives numerous maternal physiological adaptations to ensure the continuation of pregnancy and to facilitate fetal growth, including broad and potent modulation of the maternal immune system to promote maternal-fetal tolerance. In this brief review, we provide an overview of the immunomodulatory functions of progesterone in the decidua, placenta, myometrium, and maternal circulation during pregnancy. Specifically, we summarize current evidence of the regulated functions of innate and adaptive immune cells induced by progesterone and its downstream effector molecules in these compartments, including observations in human pregnancy and in animal models. Our review highlights the gaps in knowledge of interactions between progesterone and maternal cellular immunity that may direct future research.

Sex-Steroid Signaling in Lung Diseases and Inflammation

Sex/gender difference exists in the physiology of multiple organs. Recent epidemiological reports suggest the influence of sex-steroids in modulating a wide variety of disease conditions. Sex-based discrepancies have been reported in pulmonary physiology and various chronic inflammatory responses associated with lung diseases like asthma, chronic obstructive pulmonary disease (COPD), pulmonary fibrosis, and rare lung diseases. Notably, emerging clinical evidence suggests that several respiratory diseases affect women to a greater degree, with increased severity and prevalence than men. Although sex-specific differences in various lung diseases are evident, such differences are inherent to sex-steroids, which are major biological variables in men and women who play a central role to control these differences. The focus of this chapter is to comprehend the sex-steroid biology in inflammatory lung diseases and to understand the mechanistic role of sex-steroids signaling in regulating these diseases. Exploring the roles of sex-steroid signaling in the regulation of lung diseases and inflammation is crucial for the development of novel and effective therapy. Overall, we will illustrate the importance of differential sex-steroid signaling in lung diseases and their possible clinical implications for the development of complementary and alternative medicine to treat lung diseases.

Safety and value of skin test to sex hormones and sex hormone sensitivity desensitization in women with premenstrual syndrome

Background

Hypersensitivity to one's own sex hormones is not a new concept but it is an underappreciated one. Such a phenomenon may explain a large proportion of symptoms related to the menstrual cycle (such as premenstrual syndrome, PMS), cyclic pain syndromes or unexplained infertility. In this study we propose a novel diagnostic tool of hormonal skin testing which reveals sex hormones sensitivity with high clinical correlation, and a subsequent successful desensitization technique.

Methods

A group of 35 women with confirmed diagnosis of PMS were enrolled in the study in which they underwent a hormonal skin diagnostic skin testing procedure by intradermal injections of Progesterone (P), Estradiol (E2), Estrone (E1) and Estriol (E3). Skin reaction was monitored, and according to the reaction the patients were treated by serial desensitization by similar serial injections or placebo solvent. Response to treatment was monitored by assessing the change in the severity of PMS related symptoms.

Results

We show a positive correlation between PMS severity and skin sensitivity to sex hormones. Subsequent desensitization procedure led to a significant improvement in the severity of PMS related symptoms.

Conclusions

The testing and desensitization procedure is safe, sensitive and bares a high therapeutic potential in approach to resistant hormonal cycle related syndromes.

ClinicalTrials.gov Identifier

NCT00873262: Evaluation of Safety/Efficacy of Diagnostic Skin Test Panel and Desensitization Hormone Kit for Treatment of Premenstrual Syndrome (PMS) 2009.

Langerhans cell-like dendritic cells treated with ginsenoside Rh2 regulate the differentiation of Th1 and Th2 cells in vivo

Ginsenoside Rh2 is one of the rare ginsenosides extracted from Panax ginseng C. A. Mey. The anti-allergic activity of ginsenoside Rh2 has been documented in some literature. In this work, an anti-allergic mechanism of ginsenoside Rh2 was investigated by focusing on the differentiation of T cells through Langerhans cells (LCs). Langerhans cell-like dendritic cells (LDCs) were generated in vitro and were used as substitute for LCs.In vivo the mRNA expression for IFN-γ and CXCR3 of T cells was increased after being injected with ginsenoside Rh2-treated LDCs thereby increasing the concentration of IFN-γ in the culture supernatants of CD3+/CD28+ T lymphocytes. However,in vitro, the expression of mRNA for CD40 and CD80 on ginsenoside Rh2-treated LDCs was up-regulated significantly and the endocytic activity of LDCs was down-regulated slightly. These findings indicate that T cells differentiation could be regulated by ginsenoside Rh2 through LDCs in vivo by altering the antigen presenting capacity, maturation and phagocytosis of LDCs.

Progesterone-driven local regulatory T cell induction does not prevent fetal loss in the CBA/J×DBA/2J abortion-prone model

PROBLEM

Best known for its endocrine and immunologic properties, progesterone (P4) is a pivotal player for pregnancy success. However, the immunologic actions underlying P4 protection are not completely understood. Here, we investigated whether P4 application in a murine abortion-prone combination regulates regulatory T cells (Treg) and dendritic cells (DCs) and thereby affects pregnancy outcome.

METHOD OF STUDY

Progesterone or vehicle was applied to DBA/2J-mated CBA/J abortion-prone animals in early pregnancy. On gestation day 10, peripheral and local DC and Treg numbers were analyzed and pregnancy outcome was determined.

RESULTS

Progesterone application provoked a significant increase in the uterine Treg pool but did not alter the abortion rate. Moreover, no significant changes could be observed in peripheral Treg levels and DC numbers after P4 application.

CONCLUSIONS

Our findings suggest that P4-induced local Treg elevation is not sufficient to overcome fetal rejection in this specific model of disturbed fetal tolerance.

Immune-endocrine crosstalk during pregnancy

The success of pregnancy depends mostly on a synchronized immune-endocrine crosstalk at the maternal-fetal interface. Hormones are important in terms of maintaining the suitable environment and sufficient nutrition for the developing fetus. They also play a major role during the process of parturition and lactation. Maternal immunomodulation is important for the tolerance of semiallogeneic fetus. This is achieved in concert with a variety of endocrine stimulation. Estrogen, progesterone, and Human Chorionic Gonadotropin play a major role in immune modulation during pregnancy. Hormones modulate B cells, dendritic cells, uterine natural killer cells, macrophages, neutrophils to adopt fetal friendly immune phenotypes. Recently the use of hormones in assisted reproductive technology has been found to improve the pregnancy outcome. The present review focuses on the pregnancy-related hormones, their role in immunomodulation for successful pregnancy outcome. This also shed light on the immune-endocrine crosstalk at maternal-fetal interface during pregnancy.

[Pregnancy-associated hormones and fetal-maternal relations]

Pregnancy is an immunological paradox that implies that a semi-allogeneic fetus is not rejected by the maternal immune system, from implantation of the embryo to delivery. Progesterone (P4), estradiol (E2) and human chorionic gonadotropin (hCG), contribute to the transformation of immune cells in a transient tolerance state, necessary to the maintenance of pregnancy. The effects of pregnancy hormones depend probably of their maternal plasma level. hCG is dangerous at high concentrations because it can stimulate autoantibodies production, whereas in physiological concentrations, hCG, P4 and E2 upregulate immune response expanding regulatory T and B cells, allowing the fetus to grow within the maternal uterus in a protective environment. A second example of fetal-maternal relation found recently is the role of maternal nutrition on development of the fetal hypothalamic neurons. Experiments in mice fed on a high fat diet reveal a critical timing when altered maternal metabolism affect formation of hypothalamic neurocircuits of the offspring and predispose him to long-term metabolic disorders.

Immune Modulatory Effects of Human Chorionic Gonadotropin on Dendritic Cells Supporting Fetal Survival in Murine Pregnancy

Dendritic cells (DCs) are critically involved in the determination of immunity vs. tolerance. Hence, DCs are key regulators of immune responses either favoring or disfavoring fetal survival. Several factors were proposed to modulate DC phenotype and function during pregnancy. Here, we studied whether the pregnancy hormone human chorionic gonadotropin (hCG) is involved in DC regulation. In vitro, bone marrow-derived DCs (BMDCs) were stimulated in the presence or absence of urine-purified or recombinant hCG (rhCG) preparations. Subsequently, BMDC maturation was assessed. Cytokine secretion of activated BMDCs and their capability to enforce TH1, TH2, TH17, or Treg cell differentiation was determined after rhCG treatment. Moreover, the in vivo potential of hCG-modulated BMDCs to influence pregnancy outcome, Treg cell number, and local cytokine expression was evaluated after adoptive transfer in a murine abortion-prone model before and after conception. Both hCG preparations impaired the maturation process of BMDCs. rhCG treatment did neither alter cytokine secretion by BMDCs nor their ability to drive TH1, TH2, or TH17 differentiation. rhCG-treated BMDCs augmented the number of Treg cells within the T cell population. Adoptive transfer of rhCG-treated BMDCs after conception did not influence pregnancy outcome. However, transfer of hCG-treated BMDCs prior to mating had a protective effect on pregnancy. This positive effect was accompanied by increased Treg cell numbers and decidual IL-10 and TGF-β expression. Our results unveil the importance of hCG in retaining DCs in a tolerogenic state, thereby promoting Treg cell increment and supporting fetal survival.

Medroxyprogesterone acetate impairs human dendritic cell activation and function

STUDY QUESTION

Does medroxyprogesterone acetate (MPA) impair human dendritic cell (DC) activation and function?

SUMMARY ANSWER

In vitro MPA treatment suppressed expression of CD40 and CD80 by human primary DCs responding to Toll-like receptor 3 (TLR3) agonist stimulation (i.e. DC activation). Moreover, this MPA-mediated decrease in CD40 expression impaired DC capacity to stimulate T cell proliferation (i.e. DC function).

WHAT IS KNOWN ALREADY

MPA is the active molecule in Depo-Provera(®) (DMPA), a commonly used injectable hormonal contraceptive (HC). Although DMPA treatment of mice prior to viral mucosal tissue infection impaired the capacity of DCs to up-regulate CD40 and CD80 and prime virus-specific T cell proliferation, neither DC activation marker expression nor the ability of DCs to promote T cell proliferation were affected by in vitro progesterone treatment of human DCs generated from peripheral blood monocytes.

STUDY DESIGN, SIZE, DURATION

This cross-sectional study examined MPA-mediated effects on the activation and function of human primary untouched peripheral blood DCs.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Human DCs isolated from peripheral blood mononuclear cells by negative immunomagnetic selection were incubated for 24 h with various concentrations of MPA. After an additional 24 h incubation with the TLR3 agonist polyinosinic:polycytidylic acid (poly I:C), flow cytometry was used to evaluate DC phenotype (i.e. expression of CD40, CD80, CD86, and HLA-DR). In separate experiments, primary untouched human DCs were sequentially MPA-treated, poly I:C-activated, and incubated for 7 days with fluorescently labeled naïve allogeneic T cells. Flow cytometry was then used to quantify allogeneic T cell proliferation.

MAIN RESULTS AND THE ROLE OF CHANCE

Several pharmacologically relevant concentrations of MPA dramatically reduced CD40 and CD80 expression in human primary DCs responding to the immunostimulant poly I:C. In addition, MPA-treated DCs displayed a reduced capacity to promote allogeneic CD4(+) and CD8(+) T cell proliferation. In other DC: T cell co-cultures, the addition of antibody blocking the CD40-CD154 (CD40L) interaction mirrored the decreased T cell proliferation produced by MPA treatment, while addition of recombinant soluble CD154 restored the capacity of MPA-treated DCs to induce T cell proliferation to levels produced by non-MPA-treated controls.

LIMITATIONS, REASON FOR CAUTION

While our results newly reveal that pharmacologically relevant MPA concentrations suppress human DC function in vitro, additional research is needed to learn if DMPA similarly inhibits DC maturation and function in the human female genital tract.

WIDER IMPLICATIONS OF THE FINDINGS

Identification of a mechanism by which MPA impairs human DC activation and function increases the biological plausibility for the relationships currently suspected between DMPA use and enhanced susceptibility to genital tract infection.

STUDY FUNDING/COMPETING INTERESTS

Funding provided by the NIH (grant R01HD072663) and The Ohio State University College of Medicine. The authors have no conflicts of interest to declare.

Sex steroid signaling: implications for lung diseases

There is increasing recognition that sex hormones (estrogen, progesterone, and testosterone) have biological and pathophysiological actions in peripheral, non-reproductive organs, including the lung. Clinically, sex differences in the incidence, morbidity and mortality of lung diseases such as asthma, chronic obstructive pulmonary disease (COPD), pulmonary fibrosis, lung cancer and pulmonary hypertension have been noted, although intrinsic sex differences vs. the roles of sex steroids are still not well-understood. Accordingly, it becomes important to ask the following questions: 1) Which sex steroids are involved? 2) How do they affect different components of the lung under normal circumstances? 3) How does sex steroid signaling change in or contribute to lung disease, and in this regard, are sex steroids detrimental or beneficial? As our understanding of sex steroid signaling in the lung improves, it is important to consider whether such information can be used to develop new therapeutic strategies to target lung diseases, perhaps in both sexes or in a sex-specific manner. In this review, we focus on the basics of sex steroid signaling, and the current state of knowledge regarding how they influence structure and function of specific lung components across the life span and in the context of some important lung diseases. We then summarize the potential for sex steroids as useful biomarkers and therapeutic targets in these lung diseases as a basis for future translational research in the area of gender and individualized medicine.

Endocrine factors modulating immune responses in pregnancy

How the semi-allogeneic fetus is tolerated by the maternal immune system remains a fascinating phenomenon. Despite extensive research activity in this field, the mechanisms underlying fetal tolerance are still not well understood. However, there are growing evidences that immune–immune interactions as well as immune–endocrine interactions build up a complex network of immune regulation that ensures fetal survival within the maternal uterus. In the present review, we aim to summarize emerging research data from our and other laboratories on immune modulating properties of pregnancy hormones with a special focus on progesterone, estradiol, and human chorionic gonadotropin. These pregnancy hormones are critically involved in the successful establishment, maintenance, and termination of pregnancy. They suppress detrimental maternal alloresponses while promoting tolerance pathways. This includes the reduction of the antigen-presenting capacity of dendritic cells (DCs), monocytes, and macrophages as well as the blockage of natural killer cells, T and B cells. Pregnancy hormones also support the proliferation of pregnancy supporting uterine killer cells, retain tolerogenic DCs, and efficiently induce regulatory T (Treg) cells. Furthermore, they are involved in the recruitment of mast cells and Treg cells into the fetal–maternal interface contributing to a local accumulation of pregnancy-protective cells. These findings highlight the importance of endocrine factors for the tolerance induction during pregnancy and encourage further research in the field.

Profibrotic interleukin-33 is correlated with uterine leiomyoma tumour burden

STUDY QUESTION

Are interleukin-33 (IL-33) serum levels higher in women with uterine leiomyoma compared with controls without leiomyoma?

SUMMARY ANSWER

Serum IL-33 is elevated in women with uterine leiomyoma and correlated with features of uterine leiomyoma tumour burden, namely fibroid number, size and weight.

WHAT IS KNOWN ALREADY

Uterine leiomyomas are the most common benign tumours in premenopausal women associated with major tissue fibrosis. IL-33 is a cytokine involved in fibrotic disorders. The potential role of IL-33 in leiomyoma has not been reported before.

STUDY DESIGN, SIZE, DURATION

This is a prospective laboratory study conducted in a tertiary-care university hospital between January 2005 and December 2010. We investigated non-pregnant, 42-year-old patients (n = 151) during surgery for a benign gynaecological condition.

PARTICIPANTS/MATERIALS, SETTING, METHODS

After complete surgical exploration of the abdominopelvic cavity, 59 women with histologically proved uterine leiomyoma and 92 leiomyoma-free control women were enrolled. Women with endometriosis or past history of ovarian malignancy and borderline tumours were not included. The control group included women with benign ovarian cysts, paratubal cysts or tubal defects without any evidence of uterine leiomyoma. For each patient, a structured questionnaire was completed during a face-to-face interview conducted by the surgeon during the month preceding surgery. Serum samples were obtained in the month preceding the surgical procedures according to the menstrual phase or hormonal therapy. IL-33 was measured in sera by enzyme-linked immunosorbent assay, and correlation of IL-33 concentration with the extent and severity of the disease was investigated.

MAIN RESULTS AND THE ROLE OF CHANCE

IL-33 was detected in 32 (54.2%) women with leiomyoma and 18 (19.6%) controls (P < 0.001). Serum IL-33 was higher in women with leiomyoma (median, 140.1 pg/ml; range, 7.5-2247.7) than in controls (median, 27.8 pg/ml; range, 7.5-71.6; P = 0.002). We found positive correlations between serum IL-33 concentration and leiomyoma features, such as fibroid weight (r = 0.630; P = 0.001) and size (r = 0.511; P = 0.018) and the number of fibroids (r = 0.503; P = 0.003).

LIMITATIONS, REASONS FOR CAUTION

There was a possible selection bias due to inclusion of only surgical patients. Therefore our control group consisted of women who underwent surgery for benign gynaecological conditions. This may lead to biases stemming from the fact that certain of these conditions, such as tubal infertility or ovarian cysts, might be associated with altered serum IL-33 levels.

WIDER IMPLICATIONS OF THE FINDINGS

We demonstrate for the first time that elevated serum IL-33 levels are associated with the existence of uterine leiomyoma. However, even if an association does not constitute proof of cause and effect, investigating the mechanisms that underlie fibrogenesis associated with leiomyomas is a step towards understanding this enigmatic disease. This study opens the doors to future, more mechanistics studies to establish the exact role of IL-33 in uterine leiomyomas pathogenesis.

STUDY FUNDING/COMPETING INTEREST(S)

No funding, no conflict of interest.

Differential neutrophil gene expression in early bovine pregnancy

BACKGROUND

In food production animals, especially cattle, the diagnosis of gestation is important because the timing of gestation directly affects the running of farms. Various methods have been used to detect gestation, but none of them are ideal because of problems with the timing of detection or the accuracy, simplicity, or cost of the method. A new method for detecting gestation, which involves assessing interferon-tau (IFNT)-stimulated gene expression in peripheral blood leukocytes (PBL), was recently proposed. PBL fractionation methods were used to examine whether the expression profiles of various PBL populations could be used as reliable diagnostic markers of bovine gestation.

METHODS

PBL were collected on days 0 (just before artificial insemination), 7, 14, 17, 21, and 28 of gestation. The gene expression levels of the PBL were assessed with microarray analysis and/or quantitative real-time reverse transcription (q) PCR. PBL fractions were collected by flow cytometry or density gradient cell separation using Histopaque 1083 or Ficoll-Conray solutions. The expression levels of four IFNT-stimulated genes, interferon-stimulated protein 15 kDa (ISG15), myxovirus-resistance (MX) 1 and 2, and 2'-5'-oligoadenylate synthetase (OAS1), were then analyzed in each fraction through day 28 of gestation using qPCR.

RESULTS

Microarray analysis detected 72 and 28 genes in whole PBL that were significantly higher on days 14 and 21 of gestation, respectively, than on day 0. The upregulated genes included IFNT-stimulated genes. The expression levels of these genes increased with the progression of gestation until day 21. In flow cytometry experiments, on day 14 the expression levels of all of the genes were significantly higher in the granulocyte fraction than in the other fractions. Their expression gradually decreased through day 28 of gestation. Strong correlations were observed between the expression levels of the four genes in the granulocyte fractions obtained with flow cytometry and with density gradient separation.

CONCLUSIONS

The expression profiles of ISG15, MX1, MX2, and OAS1 could be a useful diagnostic biomarker of bovine gestation. Assessing the expression levels of these genes in a granulocyte fraction obtained with density gradient separation is a practical way of detecting gestation in cows within three weeks of insemination.

Dendritic cell activation and memory cell development are impaired among mice administered medroxyprogesterone acetate prior to mucosal herpes simplex virus type 1 infection

Epidemiological studies indicate that the exogenous sex steroid medroxyprogesterone acetate (MPA) can impair cell-mediated immunity, but mechanisms responsible for this observation are not well defined. In this study, MPA administered to mice 1 wk prior to HSV type 1 (HSV-1) infection of their corneal mucosa impaired initial expansion of viral-specific effector and memory precursor T cells and reduced the number of viral-specific memory T cells found in latently infected mice. MPA treatment also dampened expression of the costimulatory molecules CD40, CD70, and CD80 by dendritic cells (DC) in lymph nodes draining acute infection, whereas coculture of such DC with T cells from uninfected mice dramatically impaired ex vivo T cell proliferation compared with the use of DC from mice that did not receive MPA prior to HSV-1 infection. In addition, T cell expansion was comparable to that seen in untreated controls if MPA-treated mice were administered recombinant soluble CD154 (CD40L) concomitant with their mucosal infection. In contrast, the immunomodulatory effects of MPA were infection site dependent, because MPA-treated mice exhibited normal expansion of virus-specific T cells when infection was systemic rather than mucosal. Taken together, our results reveal that the administration of MPA prior to viral infection of mucosal tissue impairs DC activation, virus-specific T cell expansion, and development of virus-specific immunological memory.

Stromal-epithelial interactions modulate the effect of ovarian steroids on goat uterine epithelial cell interleukin-18 release

A primary role of epithelial-stromal interactions in mediating steroid hormone action in the uterus has been established. The present study was undertaken to determine the mode of ovarian steroid action in regulating IL-18 release by goat endometrial epithelial cells (EECs) in the presence and absence of endometrial stromal cells (ESCs). Primary and telomerase-immortalized goat EECs grown alone or cocultured with ESCs were treated with two ovarian steroids, 17β-estradiol (E(2)) and progesterone (P(4)). The IL-18 mRNA and protein expression in EECs were studied by reverse transcript (RT) PCR, ELISA, and Western blot assay. The E(2) and/or P(4) treatment of EECs led to a significant increase in both IL-18 mRNA and protein expression either in the primary or in the immortalized EECs compared with that in EECs without the steroid treatment. However, in the presence of ESCs, IL-18 expression by EECs treated with steroids was significantly decreased compared with cells untreated with E(2) and/or P(4). In addition, significantly high abundance of IL-18 mRNA and protein expression by primary and telomerase-immortalized goat EECs was observed in the presence of ESCs compared with those cells without ESCs. These findings suggest that steroids are important for the control of IL-18 expression in goat EECs. Underlying ESCs are needed to mediate the inhibitory effects of steroids on the IL-18 secretory activity of goat EECs in vitro. The IL-18 abundance expressed by goat EECs in vitro are enhanced by underlying ESCs without the treatment of E(2) and/or P(4).

Immunosuppressive effect of progesterone on dendritic cells in mice

Progesterone has been demonstrated to be involved in maintaining pregnancy by regulating immunocytes. Dendritic cells (DCs), the most potent triggers of the adaptive immune response, express receptors for steroid hormones and are regarded as one of the primary targets of progesterone. However, the functional modification of DCs by progesterone remains poorly understood. Here, we report that progesterone does not affect the morphology or apoptosis of murine bone marrow-derived DCs. Progesterone-treated DCs were characterized by decreased expression of Ia (MHC class II), CD80 and CD86, increased production of IL-10, and decreased secretion of IL-12. Compared with mature DCs (mDCs), activated progesterone-treated DCs had a reduced capacity to stimulate CD4(+) T cell proliferation. The observation that progesterone-treated DCs could attenuate delayed-type hypersensitivity (DTH) responses in vivo suggests that progesterone mediates suppressive DC activity. However, transfer of progesterone-treated DCs into the peritoneal cavity of mice did not elevate the percentage of CD4(+)CD25(+)Foxp3(+) regulatory T cells in the spleen. Overall, our study helps to increase understanding of the role of DCs exposed to progesterone in the maintenance of pregnancy.

Immunology of Toxoplasma gondii

Toxoplasma gondii is an obligate intracellular parasite. Following oral infection the parasite crosses the intestinal epithelial barrier to disseminate throughout the body and establish latent infection in central nervous tissues. The clinical presentation ranges from asymptomatic to severe neurological disorders in immunocompromised individuals. Since the clinical presentation is diverse and depends, among other factors, on the immune status of the host, in the present review, we introduce parasitological, epidemiological, clinical, and molecular biological aspects of infection with T. gondii to set the stage for an in-depth discussion of host immune responses. Since immune responses in humans have not been investigated in detail the present review is exclusively referring to immune responses in experimental models of infection. Systemic and local immune responses in different models of infection are discussed, and a separate chapter introduces commonly used animal models of infection.

Membrane progesterone receptor expression in mammalian tissues: a review of regulation and physiological implications

The recent discovery of a novel, membrane localized progestin receptor (mPR) unrelated to the classical progesterone receptor (PR) in fishes and its subsequent identification in mammals suggests a potential mediator of non-traditional progestin actions, particularly in tissues where PR is absent. While early studies on mPR focused on final oocyte maturation in fishes, more current studies have examined mPRs in multiple mammalian systems in both reproductive and non-reproductive tissues as well as in diseased tissues. Here we review the current data on mPR in mammalian systems including male and female reproductive tracts, liver, neuroendocrine tissues, the immune system and breast and ovarian cancer. We also provide new data demonstrating mPR expression in the RAW 264.7 immune cell line and bone marrow-derived macrophages as well as mPR expression and downstream gene regulation in ovarian cancer cells.

Differential modulation of TLR3- and TLR4-mediated dendritic cell maturation and function by progesterone

The role of progesterone in modulating dendritic cell (DC) function following stimulation of different TLRs is relatively unknown. We compared the ability of progesterone to modulate murine bone marrow-derived DC cytokine production (IL-6 and IL-12) and costimulatory molecule expression (CD40, CD80, and CD86) induced by either TLR3 or TLR4 ligation and determined whether activity was via the progesterone receptor (PR) or glucocorticoid receptor (GR) by comparative studies with the PR-specific agonist norgestrel and the GR agonist dexamethasone. Progesterone was found to downregulate, albeit with different sensitivities, both TLR3- and TLR4-induced IL-6 production entirely via the GR, but IL-12p40 production via either the GR or PR. Of particular significance was that progesterone was able to significantly inhibit TLR3- but not TLR4-induced CD40 expression in bone marrow-derived DCs. Stimulation of the PR (with progesterone and norgestrel) by pretreatment of DCs was found to sustain IFN regulatory factor-3 phosphorylation following TLR3 ligation, but not TLR4 ligation. Overall, these studies demonstrate that progesterone can differentially regulate the signaling pathways employed by TLR3 and TLR4 agonists to affect costimulatory molecule expression and cytokine production.

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.

Amyloid β peptide promotes differentiation of pro-inflammatory human myeloid dendritic cells

A key event of Alzheimer's disease (AD) pathogenesis is the production of amyloid beta peptides (A beta), which are hypothesized to lead to neurodegeneration by still unclear mechanisms, including a chronic inflammatory response characterized by innate immune cell activation and pro-inflammatory molecule release. Since dendritic cells (DCs) are central players of innate immune response and brain dendritic-like cells may have a crucial role in AD pathogenesis, this study investigates the effects of A beta on human DC functions. Myeloid DCs differentiated in the presence of A beta 42 showed an increase in survival and soluble antigen uptake, a reduction in HLA molecule expression and in IL-10 and IL-12 production. Accordingly, A beta 42-treated DCs were impaired in inducing T cell proliferation and IL-2 production. On the other hand, A beta 42 treatment provided DCs with the ability to release higher levels of IL-1 beta, IL-6 and IL-18, than control DCs. These results demonstrate that A beta 42 can modulate the immune system by inducing pro-inflammatory DC differentiation, thus gaining new insights into AD pathogenesis and immune-based therapeutic intervention.

Gender and sex hormones in multiple sclerosis pathology and therapy

Several lines of evidence indicate that gender affects the susceptibility and course of multiple sclerosis (MS) with a higher disease prevalence and overall better prognosis in women than men. This sex dimorphism may be explained by sex chromosome effects and effects of sex steroid hormones on the immune system, blood brain barrier or parenchymal central nervous system (CNS) cells. The well known improvement in disease during late pregnancy has also been linked to hormonal changes and has stimulated recent clinical studies to determine the efficacy of and tolerance to sex steroid therapeutic approaches. Both clinical and experimental studies indicate that sex steroid supplementation may be beneficial for MS. This could be related to anti-inflammatory actions on the immune system or CNS and to direct neuroprotective properties. Here, clinical and experimental data are reviewed with respect to the effects of sex hormones or gender in the pathology or therapy of MS or its rodent disease models. The different cellular targets as well as some molecular mechanisms likely involved are discussed.

The immunobiology of the innate response to Toxoplasma gondii

Toxoplasma gondii is a unique intracellular parasite. It can infect a variety of cells in virtually all warm-blooded animals. It has a worldwide distribution and, overall, around one-third of people are seropositive for the parasite, with essentially the entire human population being at risk of infection. For most people, T. gondii causes asymptomatic infection but the parasite can cause serious disease in the immunocompromised and, if contracted for the first time during pregnancy, can cause spontaneous abortion or congenital defects, which have a substantial emotional, social and economic impact. Toxoplasma gondii provokes one of the most potent innate, pro-inflammatory responses of all infectious disease agents. It is also a supreme manipulator of the immune response so that innate immunity to T. gondii is a delicate balance between the parasite and its host involving a coordinated series of cellular interactions involving enterocytes, neutrophils, dendritic cells, macrophages and natural killer cells. Underpinning these interactions is the regulation of complex molecular reactions involving Toll-like receptors, activation of signalling pathways, cytokine production and activation of anti-microbial effector mechanisms including generation of reactive nitrogen and oxygen intermediates.

Toll-like receptor-4-mediated macrophage activation is differentially regulated by progesterone via the glucocorticoid and progesterone receptors

Macrophage function has been demonstrated to be subject to modulation by progesterone. However, as this steroid hormone can act through the glucocorticoid receptor as well as the progesterone receptor, the mechanism of action has not been precisely characterized. To determine the mode of action, we compared the ability of progesterone, norgestrel (a synthetic progesterone-receptor-specific agonist) and dexamethasone (a synthetic glucocorticoid receptor agonist) to modulate macrophage function following stimulation of the Toll-like receptor-4 (TLR-4) ligand lipopolysaccharide (LPS). The results demonstrate that following stimulation of TLR-4 with LPS and cotreatment with either progesterone or dexamethasone, but not norgestrel, there is a significant reduction in nitric oxide (NO) production, indicating that this progesterone-mediated effect is through ligation of the glucocorticoid receptor. In contrast, LPS-induced interleukin-12 (IL-12) production could be downregulated by all three steroids, indicating that ligation by progesterone of either the glucocorticoid or the progesterone receptors or both could mediate this effect. While progesterone downmodulated NO-mediated killing of Leishmania donovani by activated macrophages in vitro, most probably via the glucocorticoid receptor, it had little effect on Toxoplasma gondii growth in these cells. This would suggest that progesterone-mediated increased susceptibility to T. gondii during pregnancy is more likely to be related to the ability of the hormone to downregulate IL-12 production and a type-1 response utilizing the progesterone as well as the glucocorticoid receptors.

Neuroendocrine factors alter host defense by modulating immune function

An increasing body of evidence demonstrates that there is bidirectional communication between the neuroendocrine and immune systems. Interaction between these systems results in a variety of outcomes, including the well documented "sickness behavior" elicited by cytokines of the immune system that can enter the brain and activate second messengers that modify neuronal activity. Crosstalk between the neuroendocrine and immune systems can also result in production of factors by the nervous and endocrine systems that alter immune cell function and subsequent modulation of immune responses against infectious agents and other pathogens. Continued exposure to molecules produced by the neuroendocrine system has also been known to increase susceptibility and/or severity of disease. Furthermore, neuroendocrine factors are thought to play a major role in gender-specific differences in development of certain disorders, including autoimmune/inflammatory diseases that have a two to tenfold higher incidence in females compared to males. Neuroendocrine factors can affect immune cells at the level of gene transcription but have also been shown to modify immune cell activity by interacting with intracellular molecules, resulting in modified ability of these cells to mount a potent immune response. In this review, we will consider various effects of the neuroendocrine system and its proteins on specific populations of immune cells and associated responses in host immunity against pathogens. We will further discuss how this modification of immune cell activity by the neuroendocrine system can contribute to susceptibility/severity of disease development.

Regulation of dendritic cell differentiation and function by estrogen receptor ligands

Estrogen receptor (ER) ligands can modulate innate and adaptive immunity and hematopoiesis, which may explain the clear sex differences in immune responses during autoimmunity, infection or trauma. Dendritic cells (DC) are antigen presenting cells important for initiation of innate and adaptive immunity, as well as immune tolerance. DC progenitors and terminally differentiated DC express ER, indicating the ER ligands may regulate DC at multiple developmental and functional stages. Although there are profound differences in innate immunity between males and females or upon systemic imposition of sex hormones, studies are just beginning to link these differences to DC. Our and others studies demonstrate that estradiol and other ER ligands regulate the homeostasis of bone marrow myeloid and lymphoid progenitors of DC, as well as DC differentiation mediated by GM-CSF and Flt3 Ligand. Since DC have a brief lifespan, these data suggest that relatively short exposures to ER ligands in vivo will alter DC numbers and intrinsic functional capacity related to their developmental state. Studies in diverse experimental models also show that agonist and antagonist ER ligands modulate DC activation and production of inflammatory mediators. These findings have implications for human health and disease since they suggest that both DC development and functional capacity will be responsive to the physiological, pharmacological and environmental ER ligands to which an individual is exposed in vivo.

Familial orthostatic tachycardia

PURPOSE OF REVIEW

Postural tachycardia syndrome is an autonomic disorder primarily of younger women. The patient population is heterogeneous, making diagnosis and treatment a challenge. A mutation in the norepinephrine (noradrenaline) transporter gene prompted further genetic analysis.

RECENT FINDINGS

Eleven new mutations were found in the human norepinephrine transporter gene, although none were directly associated with postural tachycardia syndrome. The 5'-flanking -1012C --> T variant of the dopamine beta-hydroxylase gene was slightly increased and protection was associated with a reduced incidence of two mutations in the endothelial nitric oxide synthase gene, and one in endothelin-1. Mutations in other disease-related genes suggest a potential relationship with the pathogenesis of postural tachycardia syndrome. Benign joint hypermobility syndrome, for example, shares similar autonomic symptoms and is linked to a mutation in tenascin-X. Additional genetic findings are discussed as potential contributors to vascular health and neurodegeneration.

SUMMARY

Genetic testing can reveal molecular mechanisms of disease and provide an additional strategy for diagnosis and treatment of heterogeneous patient populations such as postural tachycardia syndrome. It is quite likely that the pathogenesis of this disorder will be attributed to numerous genetic mutations, both subtle and overt. Therefore, continued study of the relationships between genotype and phenotype are necessary to better understand this syndrome and others with associated dysautonomia.

Progesterone is involved in the maturation of murine spleen CD11c-positive dendritic cells

Progesterone (Prog), a female sex steroid hormone, not only plays an important role in the female mammary pregnancy but also influences the immune response. In the present study, murine spleen CD11c-positive dendritic cells (SDCs) were treated with various concentrations of Prog for 24 h, and their viability, phenotype, nuclear factor kappa B P65 (NF-kappaB P65), endocytosis, stimulatory capacity, and cytokine expression were analyzed. The results showed that Prog increased the expressions of MHC-II and CD40, stimulatory capacity and intracellular levels of IL-6 and IL-10, while decreased the expressions of CD54 and IL-12, endocytosis and nuclear level of NF-kappaB P65 of SDCs. These data suggested that Prog may promote the maturation of SDCs and enhance their ability to interact with T cells so as to change the course of autoimmune diseases.

Ovarian follicular concentration of IL-12, IL-15, IL-18 and p40 subunit of IL-12 and IL-23

BACKGROUND

The aim of the study was to determine the presence of interleukin (IL)-12, IL-15, IL-18 and p40 subunit of IL-12/IL-23 in follicular fluid from spontaneous cycles and the relation between the concentration of selected cytokines and IVF-embryo transfer outcome.

METHODS

IVF-embryo transfer and enzyme immunoassay (EIA) (R&D Systems, Minneapolis, MN, USA and MBL, Nagoya, Japan) were used.

RESULTS

Follicular fluid of women included in the IVF-embryo transfer procedure contained common p40 subunit of IL-12/IL-23 (median 70.1 pg/ml), IL-15 (median 1.3 pg/ml) and IL-18 (median 38.2 pg/ml). There was a significant negative correlation between follicular fluid concentrations of IL-15 and IL-18 (R=-0.392, P=0.003). Significantly higher concentrations of common p40 subunit of IL-12/IL-23 (median 79.8 pg/ml) were found in the follicular fluid taken from follicles containing oocytes, when compared with those without an oocyte (median 44.5 pg/ml, P=0.006). Patients who achieved clinical pregnancy had significantly decreased concentration of IL-15 (median 0.8 pg/ml) compared with patients without successful IVF-embryo transfer outcome (median 1.4 pg/ml, P=0.047).

CONCLUSION

Follicular fluid collected from spontaneous cycles contains detectable levels of p40 subunit of IL-12/IL-23, IL-15 and IL-18. Increased concentrations of p40 subunit of IL-12/IL-23 in follicles containing oocytes suggest an important role of this cytokine in reproduction. Possible negative value of IL-15 as a predictor of IVF-embryo transfer success remains to be determined.