Summary
Objective. The aim of this review is to summarize current knowledge on the relationship between natural killer (NK) cells and female fertility along with other reproductive outcomes as well as to provide an overview of possibilities of laboratory diagnostics in the field.
Methods. The search of relevant literature was conducted in Pubmed and Web of Science medical databases as well as in the specialized search engine Google Scholar. Further selection of publications was done according to the recommendations of the PRISMA statement.
Literature review. By secreting cytokines, matrix metalloproteinases and angiogenic factors uterine NK (uNK) cells are a crucial part of the early embrio development. While they are involved in multiple processes such as angiogenesis, decidualization, formation of the placenta, invasion of the trophoblast and immune defense mechanisms of the embrio, dysfunctional uNK cells as well as their quantitative abnormalities may be involved in the pathogenesis of various reproductive disorders such as recurrent miscarriages or infertility. Further research is required in order to evaluate the possibility of immunomodulatory treatment with the aim of improving reproductive outcomes.
Conclusion. Despite rising interest in the hypotheses of immunological infertility, research data regarding the role of NK cells in female reproduction remains multifaceted. Further research is required in order to assess the precise mechanisms by which NK cells and their subtypes act in the reproductive system. Evaluating the potential role of NK cell tests in females with unexplained infertility or recurrent miscarriages while also exploring the possibility of immunomodulatory treatment in assisted reproduction remains a topic for future research.
