The predictive value of NKG2C+NK cells and LILRB1+NK cells in recurrent spontaneous abortion

Problem The maternal-fetal immune abnormalities can result in recurrent spontaneous abortion (RSA). The role of NKG2C(+) and LILRB1(+) pNK subsets in predicting pregnancy loss is uncertain. Method of Study In this study, we aimed to compare the percentage of CD3(-)CD56(+) NK cells, NKG2C(+) NK cells, and LILRB1(+) NK cells in peripheral blood between healthy pregnant women (HC group), RSA women followed by normal pregnancy (RSA-N group) and RSA women followed by abortion (RSA-A group) in the first trimester via flow cytometry, and explore the prediction value of NKG2C(+) and LILRB1(+) NK cells for pregnancy loss in RSA via ROC curve. The MFI of NKG2C and LILRB1 of dNK were compared between and HC and RSA-A groups. Results The percentage of CD3-CD56(+) pNK cells between HC, RSA-N, and RSA-A groups shows no significant difference. In peripheral blood, the percentage of NKG2C(+) NK cells were significantly increased in the RSA-A group than HC group and RSA-N group, and the percentage of LILRB1(+) NK cell were significantly decreased in the RSA-A group. The MFI of NKG2C and LILRB1 of dNK showed a similar trend with peripheral blood between HC and RSA-A groups. The NKG2C(+) and LILRB1(+) NK cells were an independent risk factor for predicting pregnancy loss in RSA patients, with an area under the ROC curves (AUC) of .77 and .71 respectively. Conclusion Women with recurrent spontaneous abortion have abnormal NKG2C(+) and LILRB1(+) pNK subsets, which could reflect immune abnormalities at the maternal-fetal interface, and NKG2C(+) and LILRB1(+) pNK subsets could be a good indicator for the prediction of pregnancy loss.