Research progress in the mechanism of action of NK cell-related receptors during recurrent spontaneous abortion

Abstract

Recurrent spontaneous abortion (RSA) refers to multiple spontaneous abortions with the same sexual partner; In 2020, Chinese expert consensus suggested that it should be defined as the loss of the embryo or fetus before 28 weeks of gestation with the same sexual partner for two or more times in a row, including the biochemical pregnancy that occurred several times in a row. The pathogenesis of RSA is complex and diverse. At present, the pathogenesis factors have been widely recognized by the industry, including genetic factors, endocrine factors, anatomical abnormalities, infectious factors and immune factors. Among them, the role of immune factors such as T lymphocytes, dendritic cells and natural killer cells (NK) in the occurrence and development of RSA has attracted wide attention, especially NK cells. NK cells are an important part of human immune system. The specific surface molecules of Decidual natural killer cell (dNK) play an immunomodulatory role in the invasion of trophoblast cells and the remodeling of uterine spiral artery during pregnancy, which is particularly important in the early gestation period. The function of dNK cells is tightly regulated by a balance between activation and inhibition signals transmitted by the various family of receptors (NK cell receptors, NKRS) that DNK cells express. In this paper, the existing research progress of decidual NK cells on the mechanism of its receptors in the process of recurrent spontaneous abortion will be reviewed as follows.