Effects of immunotherapy on CD69 expression on NK cells at the fetomaternal interface and the relationship with the outcomes of murine fetuses and pups / 中国病理生理杂志

ABSTRACT

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 pups. 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 growth curves and Kaplan-Meier survival graphs of pups were constructed throughout postnatal days 1 to 21. In addition, the level of CD69 expression on NK cells at the fetomaternal interface with and without LIT were determined by two-color flow cytometric analysis, stained with PE-CD69 and FITC-DX5. The subpopulation of CD16/CD32 + NK cells was also evaluated. RESULTS: Statistically significant differences were observed between CBA/J?DBA/2 mice and normal fertile controls in the median increase of maternal weight during pregnancy, the number of pups born per litter, the median neonatal weight on postnatal day 1, and the resorption rate of fetuses. The proportion of CD69 +DX5 + cells which represents activated NK cells was significantly higher in CBA/J?DBA/2 mice compared with normal fertile controls, while efficient LIT was able to dramatically decrease the expression of CD69 on NK cells at the fetomaternal interface and this was associated with the decrease of resorption rate accordingly. CONCLUSION: The fraction 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 via decreasing the expression of CD69 molecules on NK cells at the fetomaternal interface.