Study On Characteristics Of T Lymphocyte Subsets In Follicular Fluid Of Infertile Women With And Without Polycystic Ovary Syndrome

Polycystic ovary syndrome(PCOS)is the most common endocrine disorder in women at their reproductive age.It's a multi-factor and multi-dimensionsyndrome that characterized by heterogeneous presentation of hyperandrogenism,ovulatory dysfunction,and polycystic ovarian morphology(PCOM).The clinical presentation of PCOS varies widely,including infertility,irregular menstruation,acne,seborrheic dermatitis,hirsutism and obesity.The morbidity of PCOS is range from 6% to 10%,depending on the diagnostic criteria used.The pathogenesisof PCOS was unclear now,but hypothalamus-pituitary-ovary axis abnormal,hereditary,and metabolism disorder may play important roles in the process.In recent years,researches indicated that immune system may be involed in the pathogenesis of PCOS.It was comfirmed that patients with PCOS are under chronic low-grade inflammation status,including abnormal pro-inflammatory cytokines secretion,endothelial dysfunction,and increased leukocyte numbers.Besides,cytokine-target immunocompetent cells have been described in human preovulatory follicles,including B cells,T cells,and monocyte/macrophages.But the role of various immune cells in the pathogenesis of PCOS and its underlying mechanism still need further study.The purpose of this study is to measure the percentage,activation state,and cytokines production of T lymphocyte subsets in follicular fluid of infertile women with and without PCOS by flow cytometry,and to comfirm the dysfunction T lymphocyte subsets in follicular fluid of patients with PCOS.Further more,we analyzed the reason that led to the dysfunction T lymphocyte subsets,and found out the key factor.Our study will offer new experimental evidence for the research of PCOS pathogenesis,further comfirm the important role of immune system in this process,and provide new lines and targets for PCOS treatment.Methods: Twenty infertile women that were diagnosed as PCOS(PCOS group)according to the Rotterdam criteria were enrolled in the study.The control group contains thirty-six normally ovulating infertile women that were excluded of endocrinological disorders of the pituitary or ovary,abnormal adrenal or thyroid function.All patients are undergoing IVF-embryotransfer or intracytoplasmic sperm injection(ICSI).The follicular fluid of each patient was collected and lymphocyte was enriched,then the percentage of CD3+T,CD4+Th,CD8+Tc,and CD4+CD25+T-reg cells was detected by cell surface staining;the level of activated molecule CD25 and CD69 on the surface of CD4+Th and CD8+Tc cells was also measured.The expression of IFN-? and IL-17 A in CD4+ Th and CD8+ Tc cells after PMA and ionomycin stimulation was detected by intracellular cytokines staining.Finally,flow cytometry was used to analyze the expression of PD-1and IL-10 in CD4+ Th and CD8+ Tc cells.Results:1.The percentage of FF CD3+T cells in patients with PCOS was significantly decreased compared with patients in NOW group(66.2% ± 4.5% vs.54.8% ±5.3%,P<0.05).In all three T lymphocyte subsets that were detected,the percentage of FF CD8+ Tc cells was significantly lower in PCOS group than in NOW group(28.4% ± 3.5% vs.16.8% ± 6.2%,P<0.01),but no obvious change was found in the proportion of CD4+Th or CD4+CD25+ T-reg cells between two groups(P>0.05).2.The expression of activated molecule CD69 in PCOS group was significantly decreased both on FF CD4+Th cells(P<0.05)and CD8+Tc cells(P<0.01)as compared to NOW group.However,the level of CD25 on FF CD4+Th or CD8+Tc cells has no defferent between two groups(P>0.05).3.After PMA and ionomycin stimulation,the expression of FF IFN-? in CD4+Th and CD8+Tc cells was significantly decreased(P<0.05,P<0.01),but no obvious change was found in the expression of IL-17 A neither in CD4+Th cells nor in CD8+ Tc cells between two groups(P>0.05).4.Coincide with the decline of CD4+Th and CD8+Tc cells function in patients with PCOS,the level of lymphocyte inhibitory molecule PD-1 on these substes was significantly higher than in NOW patients(P<0.05).However,IL-10 expression in FF CD4+Th or CD8+Tc cells has no defferent between two groups(P>0.05).5.The expressions of PD-1 on CD4+ or CD8+T cellscorrelated negatively with the expressions of IFN-?in FF CD4+ and CD8+T cells(PD-1 vs.IFN-? in CD4+ and CD8+ T: r2 = 0.537 and r2 = 0.499,respectively,P<0.05).6.The expressions of PD-1 on CD4+ or CD8+T cells,which reflects T cell exhaust,correlated positively with serum E2 level in patients with PCOS(PD-1 on CD4+and CD8+ T vs.serum E2: r2 = 0.486 and r2 = 0.512,respectively,P<0.05).Conclusion:1.Our study indicates that the percentage of FF CD3+ T and CD8+ Tc cells was significantly lower in patients with PCOS than in NOW patients,and the fuction of FF CD4+ Th or CD8+ Tc cells was suppressed.2.The expressions of PD-1 on CD4+ or CD8+ T cellscorrelated negatively with the expressions of IFN-?in FF CD4+ and CD8+T cells.Thus,the suppression of T lymphocyte subsets may mediate by lymphocyte inhibitory molecule PD-1.3.The expressions of PD-1 on CD4+ or CD8+T cells,which reflects T cell exhaust,correlated positively with serum E2 level in patients with PCOS.T cell exhaust may berelated with the development of oocytes and ovulation.4.The dysfunction of T lymphocyte subsets,especially the abnormal expression of IFN-? and PD-1 may affects follicle maturation and ovulation,and it would finally cause the poor quality of ovum and dysfunction of ovulation if imbalance occurs.