Immunotherapy prevents recurrent abortion without influencing natural killer receptor status

PROBLEM: We assessed the expression of natural killer (NK) receptors in rec urrent aborters before and after immunotherapy using their husbands' periph eral blood mononuclear cells (PBMCs). METHOD OF STUDY: Using stored PBMCs from recurrent aborters before and afte r the immunotherapy, the expression of NK receptors, CD158a, CD158b, CD159 and CD94, were analyzed using monoclonal antibodies for respective receptor s. The diversity of killer activatory receptors (KARs) and killer inhibitor y receptors (KIRs) was also examined using reverse transcriptase-polymerase chain reaction (RT-PCR)single strand conformation polymorphism (SSCP) meth od. RESULTS. In recurrent aborters, no apparent changes in NK receptor expressi on and the balance between KARs and KIRs were found before and after the im munotherapy. CONCLUSION: The allo-human leukocyte antigen (HLA)-stimulation caused by th e immunotherapy for recurrent aborters did not affect the expression of NK receptors and the ratio of KARs to KIRs regardless of the outcome of subseq uent pregnancies, suggesting that recurrent aborters may benefit from the i mmunotherapy through mechanisms unrelated to alteration in NK receptor stat us.