NK cells, autoantibodies, and immunologic infertility: a complex interplay.

Area of Science:

• Reproductive Immunology
• Immunogenetics

Background:

• Infertility and recurrent spontaneous abortion (RSA) are complex conditions with increasing evidence pointing towards immunological mechanisms.
• Alloimmune and autoimmune factors, particularly involving natural killer (NK) cells and autoantibodies, are implicated in unexplained cases.

Purpose of the Study:

• To review the role of NK cells and autoantibodies in the pathogenesis of immunological infertility and RSA.
• To explore the relationship between Th1-Th2 immune responses, cytokines (IL-12, IL-15, IL-18), and NK cell activity in successful pregnancy.

Main Methods:

• Literature review focusing on immunological pathomechanisms in infertility and RSA.
• Analysis of the role of uterine NK cells in decidualization and pregnancy.
• Examination of circulating NK cell modulation in autoimmune processes.

Main Results:

• NK cells and autoantibodies are significant players in both alloimmune and autoimmune infertility and RSA.
• Uterine NK cell activity is crucial for decidualization, and alterations are linked to pregnancy impairment.
• Modulation of circulating NK cell numbers appears to be a primary event in the pathogenesis of immunological infertility.

Conclusions:

• Immunological factors, especially NK cells and autoantibodies, are critical in understanding infertility and RSA.
• NK cell dysfunction is a key contributor to reproductive failure, suggesting potential therapeutic targets.
• Further research into the interplay of immune cells and factors is essential for managing immunological infertility.