髓源性抑制细胞在妊娠过程中的变化及作用

The change and role of myeloid derived suppressor cells during pregnancy

目的探索髓源性抑制细胞(MDSC)在妊娠过程中的变化以及免疫抑制作用,为母胎免疫耐受调控提供理论基础。方法选取2014年1~12月在我院行产检的正常妊娠妇女共106例作为研究对象,孕早、中、晚期孕妇分别为24、29、32例,产妇21例。对照组为于我院行孕前检查的正常妇女,无流产史及其他基础疾病,共34例。分别采集孕早期、中期、晚期外周血以及产妇生产时外周血、脐带血、胎盘以及蜕膜组织、产后24h外周血进行检测。孕早、中、晚期孕妇分别为24、29、32例,产妇为21例。对照组为于我院行孕前检查的正常妇女,无流产史及其他基础疾病,共34例。采用流式细胞仪技术检测MDSC的比例,分析MDSC的变化。采用流式分选、纯化后的MDSC,与CD3+T细胞共培养,通过分析[3 H]胸(腺嘧啶脱氧核)苷密度分析T细胞增殖能力。结果妊娠妇女外周血MDSC的比例(6.25±3.59)%显著高于未妊娠正常女性(1.70±0.77)%(P<0.01),而孕中期外周血MDSC比例(10.43±7.22)%显著高于孕早期(3.88±1.67)%、晚期(5.25±1.91)%(P<0.01);分娩后,外周血MDSC比例(1.81±1.08)%下降至妊娠前水平。脐带血、蜕膜以及胎盘组织中MDSC的比例也维持在较高水平,脐带血MDSC比例(17.15±6.00)%显著高于蜕膜(8.65±3.67)%及胎盘(7.66±3.73)%(P<0.01)。MDSC显著抑制外周血CD3+T细胞增殖能力(P<0.01)。结论 MDSC可能参与了母胎免疫耐受的调节,抑制母体免疫排斥反应,有利于妊娠继续维持。

Objective： To investigate the changes of myeloid derived suppressor cells （MDSC） and its immune- suppressive function during pregnancy for providing more evidence for the maternal-fetal immune tolerance. Methods： A total of 106 women with normal pregnancy who were admitted to our hospital from January to December in 2014 were selected as subjects. The number of the pregnant women in the early, middle and late stage were 24,29,32 respectively, and 21 women were after delivery. Thirty four normal women without abortion history and other basic diseases were as control group. The peripheral blood from the normal pregnancy women at the first, second and third trimester, and cord blood, deciduas and placenta, as well as peripheral blood after 24 hours postpartum were collected for the analysis of MDSC percentage by flow cytometry. The effect of isolated pure MDSC on T cell proliferation was analyzed by the density of [^3H] thymidine.Results： The percentage of peripheral MDSC in pregnancy women（6.25±3.59%）was significantly increased compared with non-pregnant healthy women（ 1.7 ±0.77%） （P〈0.01）; while the percentage of MDSC in the second trimester （10. 43±7. 22 % ） was significantly higher than that in the first（3.88±1.67%）and third trimester（5.25±1.91%） （P〈0.01）. MDSC was rapidly decreased after delivery（ 1.81±1.08%）to non-pregnancy level. Besides, MDSC percentage in cord blood, deciduas and placenta were also higher. The percentage of MDSC in cord blood （17.15 ± 6.00%）was significantly higher than that in deciduas（ 8. 65 ±3.67%） and placenta （7.66 ±3.73%） （P〈0.01） . The proliferation of T cells was significantly inhibited by MDSC （P〈0.01）.Conclusions. MDSC may play a critical role in maternal-fetal immune tolerance, suppress immune response and contribute to the maintenance o{ pregnancy.