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.
(© 2022 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)