LYMPHOCYTE IMMUNOTHERAPY (LI) INCREASES SERUM LEVELS OF PROGESTERONE-INDUCED BLOCKING FACTOR (PIBF)

PROBLEM: To determine if allogenic stimulation from leukocyte immuniza tion (LI) can increase the production of an immunomodulatory protein c alled progesterone induced blocking factor (PIBF) by CD8+ T-lymphocyte s. METHOD: The study group consisted of 35 women, 29 who failed to con ceive after repeated embryo transfers (ETs) and six with recurrent spo ntaneous abortion (RSA). The women underwent LI using the male partner 's blood as the source of leukocytes. Progesterone one induced blockin g factor was measured pre- and post-LI with an immunocytochemistry met hod using a PIBF-specific polyclonal antibody. RESULTS: The mean perce ntage of lymphocytes expressing PIBF as well as the percentage of case s whose PIBF level increased to 1% or more, was significantly higher p ost-LI. Similarly post-LI, there was a significantly lower percentage of zero PIBF levels. CONCLUSIONS: Leukocyte immunization causes an inc rease in PIBF in many cases. Possibly the improved pregnancy outcome i n immunized patients with RSA or previous failure to conceive with in vitro fertilization may be partially or possibly completely explained by its stimulatory effect on PIPF.