Natural Killer Cell Cytotoxicity and Paternal Lymphocyte Immunization in Women with Recurrent Spontaneous Abortions

Abstract

PROBLEM: Natural killer (NK)‐cell cytotoxicity in women undergoing lymphocyte immunization prior to and following treatment was investigated.METHOD OF STUDY: A cohort of 33 women with a history of two or more recurrent spontaneous abortions was prospectively studied. NK‐cell cytotoxicity was determined at effector‐to‐target ratios of 50:1 and 25:1. Peripheral blood CD56+ NK‐cell, CD 19+ B‐cell, CD19+/5+ B‐l‐cell, and CD3+ pan T‐cell levels were studied by flow cytometry before and after lymphocyte immunization treatment. Maternal antipaternal T‐ and B‐cell antibody levels were measured before and after lymphocyte immunization by flow cytometric analysis. Paternal lymphocyte immunizations were given two times with a 4‐week interval. Post‐lymphocyte immunization testing was done 4 weeks after the second lymphocyte immunization. The controls were 8 normal healthy women. NK assays were done twice with an interval of 8 weeks.RESULTS: NK‐cell activity at effector‐to‐target ratios of 50:1 (P = 0.005) and 25:1 (P = 0.001) were significantly suppressed after lymphocyte immunization. CD3+ pan T‐cell levels after lymphocyte immunization were significantly increased compared with levels before lymphocyte immunization (P = 0.008). CD56+ NK‐cell levels were significantly suppressed after lymphocyte immunization (P = 0.016). There was no correlation between changes in NK cytotoxicity and differences in antipaternal lymphocyte antibody levels before or after lymphocyte immunization.CONCLUSION: Lymphocyte immunization suppresses NK‐cell cytotoxicity and CD56+ NK‐cell levels and increases the peripheral blood CD3+ T‐cell population in women with recurrent spontaneous abortions.