免疫治疗对母胎交界面NK细胞表面CD69表达水平的影响及其与鼠胚和鼠仔预后的关系

目的:研究反复自然流产(recurrent spontaneous abortion,RSA)模型CBA/J×DBA/2小鼠母胎交界面NK细胞表面CD69分子的表达水平,并评价淋巴细胞免疫治疗(lymphocyteimmunotherapy,LIT)对CD69表达水平的影响及其与鼠胚和鼠仔预后的关系。方法:评价CBA/J×DBA/2、C57BL/6×DBA/2和BALB/c×DBA/2小鼠胚胎和鼠仔的预后,绘制出生后1-21 d鼠仔离乳前生长曲线和Kaplan-Meier生存分析曲线。并且采用PE-CD69和FITC-DX5双色流式细胞术检测在有或无LIT的情况下,母胎交界面NK细胞表面CD69分子的表达水平。此外,对CD16/CD32⁺NK细胞亚群等也进行检测。结果:在孕期母鼠体重平均增长幅度、平均每窝产仔数、新生鼠仔出生第1 d平均体重和胚胎吸收率等方面,CBA/J×DBA/2小鼠与生殖力正常的对照组相比均有显著差异。在CBA/J×DBA/2小鼠中,代表活化型NK细胞的CD69⁺DX5⁺细胞比率也显著高于对照组。而有效的LIT能够显著降低CD69在母胎交界面NK细胞表面的表达水平,并相应地显著降低胚胎吸收率。结论:CD69⁺DX5⁺细胞在胚胎被排斥的机制中可能具有重要作用。有效的LIT通过降低CD69分子在母胎交界面NK细胞表面的表达水平而显著降低流产率。

Effects of immunotherapy on CD69 expre ssion on NK cells at the fetomaternal interface and the relationship with the outcomes of murine fetuses and pups

AIM: To examine the expression of CD69 on NK cells at the fetomaternal interface in CBA/J×DBA/2 mice as a model of recurrent spontaneous abortion (RSA ),and to evaluate the effects of lymphocyte immunotherapy (LIT) on the level of CD69 expression and the relationship with the outcomes of murine fetuses and pu ps. METHODS: The outcomes of murine fetuses and pups were evaluated in breeding pairs of CBA/J×DBA/2,C57BL/6×DBA/2 and BALB/c×DBA/2 mice. Both preweaning gr owth curves and Kaplan-Meier survival graphs of pups were constructed throughout postnatal days1to 21. In addition,the level of CD69 expression on NK cells a t the fetomaternal interface with and without LIT were determined by two-color f low cytometric analysis,stained with PE-CD69 and FITC-DX5. The subpopulation of CD16/CD32 + NK cells was also evaluated. RESULTS: Statistically si gn ificant differences were observed between CBA/J×DBA/2 mice and normal fertile c ontrols in t he median increase of maternal weight during pregnancy,the number of pups born per litter,the median neonatal weight on postnatal day1,and the resorption ra te of fetuses. The proportion of CD69 +DX5 + cells which represents activated NK c ells was significantly higher in CBA/J×DBA/2 mice compared with normal fertile controls,while efficient LIT was able to dramatically decrease the expression o f CD69 on NK cells at the fetomaternal interface and this was associated with th e decrease of resorption rate accordingly. CONCLUSION: The fract ion of CD69 +DX5 + cells seems to be functionally important in the mechanisms by which the embryos were rejected,whereas efficient LIT is capable of reducing the abortion rate v ia decreasing the expression of CD69 molecules on NK cells at the fetomaternal i nterface.