Immunological Aspects of Infertility-The Role of KIR Receptors and HLA-C Antigen.

The mechanisms of immune tolerance of a mother against an antigenically foreign fetus without a concomitant loss of defense capabilities against pathogens are the factors underlying the success of a pregnancy. A significant role in human defense is played by killer immunoglobulin-like receptor (KIR) receptors, which regulate the function of the natural killer (NK) cells capable of destroying antigenically foreign cells, virus-infected cells, or tumor-lesioned cells. A special subpopulation of NK cells called uterine NK cells (uNK) is found in the uterus. Disruption of the tolerance process or overactivity of immune-competent cells can lead to immune infertility, a situation in which a woman's immune system attacks her own reproductive cells, making it impossible to conceive or maintain a pregnancy. Since the prominent role of the inflammatory response in infertility, including KIR receptors and NK cells, has been postulated, the process of antigen presentation involving major histocompatibility complex (MHC) molecules (HLA) appears to be crucial for a successful pregnancy. Proper interactions between KIR receptors on female uNK cells and HLA class I molecules, with a predominant role for HLA-C, found on the surface of germ cells, are strategically important during embryo implantation. In addition, maintaining a functional balance between activating and inhibitory KIR receptors is essential for proper placenta formation and embryo implantation in the uterus. A disruption of this balance can lead to complications during pregnancy. The discovery of links between KIR and HLA-C has provided valuable information about the complexity of maternal-fetal immune interactions that determine the success of a pregnancy. The great diversity of maternal KIR and fetal HLA-C ligands is associated with the occurrence of KIR/HLA-C combinations that are more or less favorable for reproductive success.

IL-22 regulates endometrial regeneration by enhancing tight junctions and orchestrating extracellular matrix.

The uterine endometrium uniquely regenerates after menses, postpartum, or after breaks in the uterine layer integrity throughout women's lives. Direct cell-cell contacts ensured by tight and adherens junctions play an important role in endometrial integrity. Any changes in these junctions can alter the endometrial permeability of the uterus and have an impact on the regeneration of uterine layers. Interleukin 22 (IL-22) is a cytokine that is recognized for its role in epithelial regeneration. Moreover, it is crucial in controlling the inflammatory response in mucosal tissues. Here, we studied the role of IL-22 in endometrial recovery after inflammation-triggered abortion. Fecundity of mice was studied in consecutive matings of the same animals after lipopolysaccharide (LPS) (10 µg per mouse)-triggered abortion. The fecundity rate after the second mating was substantially different between IL-22 knockout (IL-22-/-) (9.1%) and wild-type (WT) (71.4%) mice (p < 0.05), while there was no difference between the groups in the initial mating, suggesting that IL-22 deficiency might be associated with secondary infertility. A considerable difference was observed between IL-22-/- and WT mice in the uterine clearance following LPS-triggered abortion. Gross examination of the uteri of IL-22-/- mice revealed non-viable fetuses retained inside the horns (delayed clearance). In contrast, all WT mice had completed abortion with total clearance after LPS exposure. We also discovered that IL-22 deficiency is associated with a decreased expression of tight junctions (claudin-2 and claudin-10) and cell surface pathogen protectors (mucin-1). Moreover, IL-22 has a role in the remodeling of the uterine tissue in the inflammatory environment by regulating epithelial-mesenchymal transition markers called E- and N-cadherin. Therefore, IL-22 contributes to the proper regeneration of endometrial layers after inflammation-triggered abortion. Thus, it might have a practical significance to be utilized as a treatment option postpartum (enhanced regeneration function) and in secondary infertility caused by inflammation (enhanced barrier/protector function).

Immune checkpoints and reproductive immunology: Pioneers in the future therapy of infertility related Disorders?

As co-stimulatory receptors, immune checkpoint molecules are found on the surface of various immune cells and transduce inhibitory signals following ligand binding. The most studied members in this regard include PD-1, TIM-3, and CTLA-4. The physiological part immune checkpoints possess is the prevention of dangerous immune attacks towards self-antigens throughout an immune response, which takes place through the negative regulation of the effector immune cells, through the induction of T-cell exhaustion, for instance. It has recently been suggested that each checkpoint reduces immunoactivation via distinct intracellular mechanisms of signaling. Regulators of immune checkpoints are supposed to participate actively in immune defense mechanisms against infections, preventing autoimmunity, transplantation, and tumor immune evasion. In pregnancy, as an active immunotolerance mechanism which is also natural, the maternal immune system encounters two simultaneous challenges; in addition to accepting the semi-allogeneic fetus, the maternal immune system should also prevent infections. In this regard, the part immune checkpoint molecules possess is particularly interesting. Herein, the current understanding of such part in reproductive immunology is described.

Functional Ambivalence of Dendritic Cells: Tolerogenicity and Immunogenicity.

Dendritic cells (DCs) are the most potent professional antigen-presenting cells (APCs) and inducers of T cell-mediated immunity. Although DCs play a central role in promoting adaptive immune responses against growing tumors, they also establish and maintain peripheral tolerance. DC activity depends on the method of induction and/or the presence of immunosuppressive agents. Tolerogenic dendritic cells (tDCs) induce immune tolerance by activating CD4+CD25+Foxp3+ regulatory T (Treg) cells and/or by producing cytokines that inhibit T cell activation. These findings suggest that tDCs may be an effective treatment for autoimmune diseases, inflammatory diseases, and infertility.

Effects of treatment with hydroxychloroquine on the modulation of Th17/Treg ratio and pregnancy outcomes in women with recurrent implantation failure: clinical trial.

AIM: The imbalance of Th17/Treg cells has been recently suggested as a new risk factors for recurrent implantation failure (RIF). Furthermore Th17/Treg cells are involved in immune regulation in peripheral blood and endometrial tissue of patients with RIF. In this research, we investigated the effects of Hydroxychloroquine (HCQ) on the level and function of Th17 and Treg cells in women with RIF. It may be possible to improve pregnancy outcomes by modulating high cytokine levels. METHODS: Women with RIF received oral HCQ (n = 60) on day 4 of the menstrual cycle and continued until day 20 of the menstrual cycle and 2 days before embryo transfer and continued until the day of the pregnancy test, for a total of 16 days in another cycle. The serum levels of IL-17 and IL-10, the expression of transcription factors related to Th17 and Treg cells and the immune-reactivity of IL-17, IL-21 as Th17 related cytokines and IL-10, TGF- ß as Treg related cytokines in endometrial tissues were evaluated by ELISA, real-time PCR, and fluorescent immunohistochemistry respectively.Results: Treatment with HCQ down-regulated Th17 related cytokines and function and up-regulated Treg related cytokines and function significantly (p < .001). RORγt, the Th17 transcription factor, expression was down-regulated and FOXP-3, the T-reg transcription factor, expression was up-regulated. The biochemical pregnancy rate was not significantly different in RIF patients before and after treatment. CONCLUSION: Our results demonstrated that the administration of HCQ in RIF women with immune cell disorders during pregnancy could affect the Th17/Treg ratio and enhance Treg and diminish Th17 responses which may be associated with successful pregnancy outcomes. However, significant difference in pregnancy outcomes was not observed in the present study.

Two of a kind? Immunological and clinical risk factors differ between recurrent implantation failure and recurrent miscarriage.

Recurrent miscarriage (RM) and recurrent implantation failure (RIF) are unsolved challenges in reproductive medicine. Whether RIF patients share the same risk factors as RM patients is a matter of debate. Besides clinical factors, immune alterations are discussed in both conditions. The scope of this study was to compare the prevalence of clinical and immunological risk factors in a large cohort of RM and RIF patients. Between 11/2011 and 02/2019, 613 RM and 185 RIF patients were included. A screening for anatomical malformations, endocrine, autoimmune, prothrombotic and parental chromosomal disorders was performed. The immune status was assessed using flow cytometry analysis of peripheral lymphocyte subpopulations and uterine natural killer cells (uNK cells) using immunohistochemistry. RM patients showed a higher rate of intrauterine adhesions and elevated antinuclear antibodies ≥ 1:160 (p < 0.05). A higher prevalence of submucous fibroids and increased factor VIII levels were observed in RIF patients (p < 0.05). The prevalence of an antiphospholipid syndrome (APLS) was low and did not differ between the two groups. RIF patients had higher numbers of peripheral regulatory T-cells (p < 0.05). Significant more RIF patients were diagnosed with elevated uNK cells (p < 0.05). Differences in clinical and immunological risk factors of RM and RIF patients reflect different entities. Lower Tregs in RM and higher uNK cells in RIF patients might be related to the previous exposure of the immune system to fetal cells. The low prevalence of an APLS indicates a potential overestimation of this factor in the pathophysiology of RM and RIF.

Potential impact of maternal vitamin D status on peripheral blood and endometrium cellular immunity in women with recurrent implantation failure.

PROBLEM: This study aims to evaluate the modulatory effects of vitamin D on peripheral blood and endometrial cellular immunity in women with recurrent implantation failure (RIF). METHOD OF STUDY: One hundred and fifty-four women with RIF were identified at a fertility center from January 2018 and March 2019. Blood and endometrium samples were collected during the mid-luteal phase before IVF treatment or pregnancy. The serum vitamin D status, NK cell cytotoxicity, Th1 cytokine production, and endometrial immune cells were detected before and after vitamin D supplementation. RESULTS: The NK cell cytotoxicity at an effector:target (E:T) ratio of 50:1 or 25:1 was significantly higher in vitamin D insufficiency group (VDI) than those in vitamin D normal group (VDN) (P < .05 each). The percentage of IFN-γ- or TNF-α-producing Th cells was significantly increased in VDI or vitamin D deficiency group (VDD) when compared with VDN (P < .05 each). The percentage of CD68+ macrophages on all endometrial cells in VDI and VDD was significantly higher than in VDN (P < .05 each), while no significant differences in the percentage of other endometrial immune cells among the three groups were observed. This dysregulation was significantly reduced with vitamin D supplementation. CONCLUSION: Our findings highlighted that vitamin D may have an important role in the regulation of not only systemic but also local immune response for optimization of maternal tolerance for implantation in women with RIF. Pre-conception optimization of vitamin D status should be considered in women with RIF.

Immunophenotypic Profiles in Polycystic Ovary Syndrome.

Polycystic ovary syndrome (PCOS) a long-known endocrinopathy and one of the most common endocrine-reproductive-metabolic disorders in women, which can lead to infertility. Although the precise etiology remains unclear, PCOS is considered as a complex genetic trait, with a high degree of heterogeneity. Besides, hormones and immune cells, including both innate and adaptive immune cells, are reportedly a cross talk in PCOS. Chronic low-grade inflammation increases autoimmune disease risk. This proinflammatory condition may, in turn, affect vital physiological processes that ultimately cause infertility, such as ovulation failure and embryo implantation. Here, we review the accumulating evidence linking PCOS with inflammatory status providing an overview of the underlying hormone-mediated dysregulation of immune cells. We mainly focus on the correlational evidence of associations between immune status in women and the increased prevalence of PCOS, along with the specific changes in immune responses. Further recognition and exploration of these interactions may help elucidate PCOS pathophysiology and highlight targets for its treatment and prevention.

Endometrial CD138 count appears to be a negative prognostic indicator for patients who have experienced previous embryo transfer failure.

OBJECTIVE: To explore the predictive value of endometrial CD138 expression in the natural cycle preceding frozen embryo transfer in patients with normal endometrial dating and histopathologic features, who previously failed the transfer of two high-quality fresh embryos. DESIGN: Retrospective analysis. SETTING: University-affiliated hospital. PATIENT(S): Women with normal endometrial dating and histopathologic features who previously failed the transfer of two high-quality fresh embryos, and who then underwent an endometrial scratching operation preceding a natural cycle. INTERVENTION(S): Paraffin-embedded endometrial samples cut into sections for immunohistochemistry staining of CD138 (syndecan-1) expression, then clinical information for these patients reviewed and analyzed. MAIN OUTCOME MEASURE(S): Clinical rates of pregnancy and implantation. RESULT(S): A total of 141 women met the inclusion criteria. Of these patients, about 31.2% (44 of 141) were positive for CD138 expression, with CD138 counts ranging from 0 to 33. Receiver operating characteristic (ROC) curves were analyzed to determine whether the number of cells expressing CD138 (CD138+ cells) predicted a successful pregnancy. The areas under the ROC curves based on CD138+ cell density and CD138+ cell count were 0.660 and 0.658, respectively. The clinical pregnancy and embryo implantation rates in patients not expressing CD138 (80.04% and 64.9%, respectively) were statistically significantly higher than rates in CD138+ patients (52.7% and 46.8%, respectively). In addition, the higher the number of cells expressing CD138, the worse the outcome of the pregnancy. Finally, clinical data showed that free pelvic fluid on the day of endometrial sampling (identified using transvaginal ultrasound) might be a risk factor for CD138 expression. CONCLUSION(S): Endometrial CD138+ count might be a valuable marker predicting pregnancy outcomes after frozen embryo transfer in patients with normal endometrial dating and histopathologic features who previously failed the transfer of two high-quality fresh embryos.

HHV-6A infection of endometrial epithelial cells affects immune profile and trophoblast invasion.

PROBLEM: We first reported human herpesvirus (HHV)-6A DNA presence in 43% of endometrial cells from women with idiopathic infertility, whereas no fertile control women harbored the virus. We investigated the effect of HHV-6A infection on the immunological status of the endometrium. METHOD OF STUDY: Endometrial biopsies, uterine flushing, and whole blood samples were collected from 67 idiopathic infertile women (mid-secretory phase). We analyzed the endometrial immunological status evaluating: (a) the effect of HHV-6A infection on endometrial immune profile analyzing the ratio of interleukin (IL)-15/ fibroblast growth factor-inducible 14 (Fn-14) and IL-18/ TNF-related weak inducer of apoptosis (TWEAK) mRNA as a biomarker of endometrial (e)natural killer activation/maturation, angiogenesis, and Th1/Th2 balance; (b) endometrial receptivity to trophoblasts in endometrial 3D in vitro model; (c) natural killer (NK) cells and T cells percentage and subpopulations by flow cytometry. RESULTS: We confirmed the presence of HHV-6A infection in a 40% of idiopathic infertile women, characterized by an immune profile reflecting eNK cell cytotoxic activation and a decrease in CD4+ CD25+ CD127dim/- regulatory T cells. The co-culture of endometrial epithelial cells with spheroids generated from the extravillous trophoblast-derived cell line JEG3 showed a twofold expansion of spheroids on endometrial epithelial-stromal cells (ESC) culture surface from HHV-6A negative women while no expansion was observed on the surface of ESC from HHV-6A positive women. CONCLUSION: The identification of an effect of HHV-6A infection on endometrial immune status opens new perspectives in idiopathic infertile women care management. In addition, it would be possible to select antiviral therapies as novel, non-hormonal therapeutic approaches to those idiopathic infertile women characterized by the presence of endometrial HHV-6A infection, to increase their pregnancy rate.

New insights of the local immune response against both fertile and infertile hydatid cysts.

BACKGROUND: Cystic echinococcosis is caused by the metacestode of the zoonotic flatworm Echinococcus granulosus. Within the viscera of the intermediate host, the metacestode grows as a unilocular cyst known as hydatid cyst. This cyst is comprised of two layers of parasite origin: germinal and laminated layers, and one of host origin: the adventitial layer, that encapsulates the parasite. This adventitial layer is composed of collagen fibers, epithelioid cells, eosinophils and lymphocytes. To establish itself inside the host, the germinal layer produces the laminated layer, and to continue its life cycle, generates protoscoleces. Some cysts are unable to produce protoscoleces, and are defined as infertile cysts. The molecular mechanisms involved in cyst fertility are not clear, however, the host immune response could play a crucial role. METHODOLOGY/PRINCIPAL FINDINGS: We collected hydatid cysts from both liver and lungs of slaughtered cattle, and histological sections of fertile, infertile and small hydatid cysts were stained with haematoxylin-eosin. A common feature observed in infertile cysts was the disorganization of the laminated layer by the infiltration of host immune cells. These infiltrating cells eventually destroy parts of laminated layer. Immunohistochemical analysis of both parasite and host antigens, identify these cells as cattle macrophages and are present inside the cysts associated to germinal layer. CONCLUSIONS/SIGNIFICANCE: This is the first report that indicates to cell from immune system present in adventitial layer of infertile bovine hydatid cysts could disrupt the laminated layer, infiltrating and probably causing the infertility of cyst.

Embryotoxic cytokines-Potential roles in embryo loss and fetal programming.

Cytokines in the reproductive tract environment at conception mediate a dialogue between the embryo and maternal tissues to profoundly influence embryo development and implantation success. Through effects on gene expression and the cell stress response, cytokines elicit an epigenetic impact with consequences for placental development and fetal growth, which in turn affect metabolic phenotype and long-term health of offspring. There is substantial evidence demonstrating that pro-survival cytokines, such as GM-CSF, CSF1, LIF, HB-EGF and IGFII, support embryos to develop optimally. Less attention has been paid to cytokines that adversely impact embryo development, including the pro-inflammatory cytokines TNF, TRAIL and IFNG. These agents elicit cell stress, impair cell survival and retard blastocyst development, and at sufficiently high concentrations, can cause embryo demise. Experiments in mice suggest these so-called 'embryotoxic' cytokines can harm embryos through pro-apoptotic and adverse programming effects, as well as indirectly suppressing uterine receptivity through the maternal immune response. Embryotrophic factors may mitigate against and protect from these adverse effects. Thus, the balance between embryotrophic and embryotoxic cytokines can impart effects on embryo development and implantation, and has the potential to contribute to endometrial 'biosensor' function to mediate embryo selection. Embryotoxic cytokines can be elevated in plasma and reproductive tract tissues in inflammatory conditions including infection, diabetes, obesity, PCOS and endometriosis. Studies are therefore warranted to investigate whether excessive embryotoxic cytokines contribute to infertility and recurrent implantation failure in women, and compromised reproductive performance in livestock animals.

Transcervical Inoculation with Chlamydia trachomatis Induces Infertility in HLA-DR4 Transgenic and Wild-Type Mice.

Chlamydia trachomatis is the leading cause of infection-induced infertility in women. Attempts to control this epidemic with screening programs and antibiotic therapy have failed. Currently, a vaccine to prevent C. trachomatis infections is not available. In order to develop an animal model for evaluating vaccine antigens that can be applied to humans, we used C. trachomatis serovar D (strain UW-3/Cx) to induce infertility in mice whose major histocompatibility complex class II antigen was replaced with the human leukocyte antigen DR4 (HLA-DR4). Transcervical inoculation of medroxyprogesterone-treated HLA-DR4 transgenic mice with 5 × 105C. trachomatis D inclusion forming units (IFU) induced a significant reduction in fertility, with a mean number of embryos/mouse of 4.4 ± 1.3 compared to 7.8 ± 0.5 for the uninfected control mice (P < 0.05). A similar fertility reduction was elicited in the wild-type (WT) C57BL/6 mice (4.3 ± 1.4 embryos/mouse) compared to the levels of the WT controls (9.1 ± 0.4 embryos/mouse) (P < 0.05). Following infection, WT mice mounted more robust humoral and cellular immune responses than HLA-DR4 mice. As determined by vaginal shedding, HLA-DR4 mice were more susceptible to a transcervical C. trachomatis D infection than WT mice. To assess if HLA-DR4 transgenic and WT mice could be protected by vaccination, 104 IFU of C. trachomatis D was delivered intranasally, and mice were challenged transcervically 6 weeks later with 5 × 105 IFU of C. trachomatis D. As determined by severity and length of vaginal shedding, WT C57BL/6 and HLA-DR4 mice were significantly protected by vaccination. The advantages and limitations of the HLA-DR4 transgenic mouse model for evaluating human C. trachomatis vaccine antigens are discussed.

PLAC1 immunization does not induce infertility in mice.

AIM: Placenta specific 1 (PLAC1) is a protein rarely expressed in normal cells, except it is important for placental development, with a possible role in the establishment of the mother-fetus interface. The gene is also highly active in a wide variety of cancers and therefore, immunization with PLAC1 peptides could possibly be part of future immunotherapeutic strategies. We investigated whether vaccination against PLAC1 could induce infertility. MATERIALS & METHODS: We inoculated female mice with PLAC1 peptides, put them in mating, measured antibody response (ELISA assay) and checked, in immunohistochemistry, binding of the induced antibodies to the native antigen. RESULTS: We demonstrated that mice consistently develop antibody responses. We also demonstrated that female mice, after being inoculated with the PLAC1 peptide mix, do became pregnant and can give birth to normal infants. CONCLUSION: PLAC1 antigens as a specific anti-cancer vaccine could induce anti-PLAC1 antibodies which do not necessarily cause infertility.

Combination of uterine natural killer cell immunoglobulin receptor haplotype and trophoblastic HLA-C ligand influences the risk of pregnancy loss: a retrospective cohort analysis of direct embryo genotyping data from euploid transfers.

OBJECTIVE: To compare maternal uterine natural killer cell immunoglobulin receptor (KIR) genotype and haplotype frequencies between patients whose euploid single-embryo transfer resulted in pregnancy loss and those that resulted in delivery and to determine if the risk of pregnancy loss was affected by the HLA-C genotype content in the embryo. DESIGN: Retrospective cohort. SETTING: Academic research center. PATIENT(S): Autologous fresh IVF cycles resulting in positive serum ß-hCG during 2009-2014. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): 1) Relative risk of pregnancy loss according to maternal KIR genotypes and haplotypes. 2) Comparison of pregnancy loss rates within each KIR haplotype according to HLA-C ligand present in trophectoderm biopsy samples. RESULT(S): A total of 668 euploid single-embryo transfers with stored maternal DNA and available preamplification DNA from prior trophectoderm biopsy samples were studied. KIR2DS1, KIR3DS1, and KIR2DS5 were more common in patients who experienced pregnancy loss. Carriers of KIR A haplotype exhibited a decreased risk of pregnancy loss compared with KIR B haplotype carriers. However, among KIR A haplotype carriers, the risk of loss was significantly influenced by whether the transferred embryo carried a C1 allele versus no C1 alleles. CONCLUSION(S): KIR A haplotype carriers experienced fewer pregnancy losses than KIR B haplotype carriers after euploid single-embryo transfer. However, this risk was modified by HLA-C alleles present in the embryo. High-risk combinations (KIR A/homozygous C2 and KIR B/homozygous C1) resulted in a 51% increased risk of loss over all other combinations.

Effect of Endometrial Injury on Secretion of Endometrial Cytokines and IVF Outcomes in Women with Unexplained Subfertility.

In order to determine the effect of endometrial injury (EI) on in vitro fertilization (IVF) outcomes in women with unexplained subfertility and explore the relationship between EI and endometrial inflammatory cytokines, 66 women with unexplained subfertility undergoing IVF treatment were recruited. 38 patients in the EI group underwent EI in the mid-luteal phase of the cycle and 28 patients in the non-EI (NEI) group. According to the pregnancy outcome, the NEI and EI groups were divided into NEI-nonpregnant (NEI-NP), NEI-pregnant (NEI-P), EI-NP, and EI-P. All patients underwent aspiration of endometrial secretions immediately before embryo transfer. The concentrations of ten mediators were measured using Milliplex Magnetic Bead assay. The clinical pregnancy was significantly higher in the EI than in the NEI group. The concentrations of interleukin- (IL-) 6, IL-8, IL-12 (p70), IL-13, interferon- (IFN-) γ, monocyte chemotactic protein- (MCP-) 1, and vascular endothelial growth factor (VEGF) were significantly higher in the EI than the NEI group. The expression of IFN-γ and VEGF in the EI-P was significantly increased compared to the EI-NP group. These findings suggest that, in women with unexplained subfertility, endometrial injury might be a potential method to improve clinical pregnancy rates by promoting the expression of IFN-γ and VEGF.

Variability in tuberculosis granuloma T cell responses exists, but a balance of pro- and anti-inflammatory cytokines is associated with sterilization.

Lung granulomas are the pathologic hallmark of tuberculosis (TB). T cells are a major cellular component of TB lung granulomas and are known to play an important role in containment of Mycobacterium tuberculosis (Mtb) infection. We used cynomolgus macaques, a non-human primate model that recapitulates human TB with clinically active disease, latent infection or early infection, to understand functional characteristics and dynamics of T cells in individual granulomas. We sought to correlate T cell cytokine response and bacterial burden of each granuloma, as well as granuloma and systemic responses in individual animals. Our results support that each granuloma within an individual host is independent with respect to total cell numbers, proportion of T cells, pattern of cytokine response, and bacterial burden. The spectrum of these components overlaps greatly amongst animals with different clinical status, indicating that a diversity of granulomas exists within an individual host. On average only about 8% of T cells from granulomas respond with cytokine production after stimulation with Mtb specific antigens, and few "multi-functional" T cells were observed. However, granulomas were found to be "multi-functional" with respect to the combinations of functional T cells that were identified among lesions from individual animals. Although the responses generally overlapped, sterile granulomas had modestly higher frequencies of T cells making IL-17, TNF and any of T-1 (IFN-γ, IL-2, or TNF) and/or T-17 (IL-17) cytokines than non-sterile granulomas. An inverse correlation was observed between bacterial burden with TNF and T-1/T-17 responses in individual granulomas, and a combinatorial analysis of pair-wise cytokine responses indicated that granulomas with T cells producing both pro- and anti-inflammatory cytokines (e.g. IL-10 and IL-17) were associated with clearance of Mtb. Preliminary evaluation suggests that systemic responses in the blood do not accurately reflect local T cell responses within granulomas.

Evaluation of cytokines in follicular fluid and their effect on fertilization and pregnancy outcome.

Cytokines in follicular fluid (FF) are important for reproduction as they modulate oocyte maturation and ovulation which influence subsequent fertilization, development of early embryo and potential for implantation. We evaluated FF cytokines in women who underwent intracytoplasmic sperm injection (ICSI) and their association with fertilized oocytes, embryo quality and pregnancy outcome. FF belonging to 38 patients including 18 polycystic ovary (PCO) and 20 male/unexplained infertility patients were investigated for granulocyte colony stimulating factor (G-CSF), regulated upon activation normal T cell expressed and presumably secreted (RANTES), tumour necrosis factor (TNFα), interferon gamma (IFNγ) and interleukins (IL-4 and IL-2) by bead-based sandwich immunoassay. Our findings revealed that on the day of oocyte retrieval, G-CSF was positively correlated with the number of fertilized oocytes, while TNFα detection was associated with reduced number of fertilized oocytes. Only G-CSF showed significant positive effect to the pregnancy outcome although the cytokines studied were not associated with embryo quality. PCO as the cause of infertility did not show an association with cytokines in FF. The functions of cytokines in reproduction are likely to be complex, and cytokine evaluation may offer insight to the understanding of the mechanisms leading to success or failure of assisted reproduction.

Luteal cells from functional and regressing bovine corpora lutea differentially alter the function of gamma delta T cells.

The luteal microenvironment is thought to direct the function of resident immune cells to facilitate either luteal function or regression. To determine if luteal cells from functional (Days 10-12) and regressing (8 h after administration of prostaglandin F2alpha) corpora lutea (CL) induce different responses in γδ T cells, luteal cells were cocultured with autologous γδ T cells isolated from peripheral blood. Proliferation, functional phenotypes, and cytokine synthesis were analyzed by flow cytometry. To determine if the luteal cells from functional CL induce hyporesponsiveness in γδ T cells, γδ(+) cells were cocultured with midcycle luteal cells and further stimulated with concanavalin A. Coculture of γδ(+) cells with midcycle luteal cells did not inhibit concanavalin A-induced proliferation. In a proliferation assay, luteal cells from midcycle CL predominantly induced proliferation of γδ(+) WC1(-) cells (P < 0.05), while luteal cells from regressing CL predominantly induced proliferation of γδ(+)WC1(+) cells (P < 0.05). Analysis of intracellular cytokines indicated that midcycle luteal cells increased the proportion of γδ(+) cells containing interleukin 10 (P < 0.05), but reduced the proportion of γδ(+) cells containing interferon gamma (IFNG; P < 0.05). There were no changes in the proportions of γδ(+) cells synthesizing interleukin 4 or tumor necrosis factor. Unexpectedly, coculture of γδ(+) cells with luteal cells from regressing CL had no effect on any of the cytokines analyzed. These data support the hypothesis that the function of resident T cells is differentially modulated depending on the status of the CL.