The progesterone receptor antagonist mifepristone does not lower serum progesterone induced blocking factor (PIBF) in the presence of progesterone.

PURPOSE: To determine if mifepristone can lower serum levels of a progesterone (P) induced immunomodulatory protein believed to be needed for the fetus to escape immune surveillance. MATERIALS AND METHODS: A female volunteer had her serum P induced blocking factor (PIBF) increased by ingestion of oral micronized P. While remaining on P mifepristone, 200 mg/day was given for six days when another serum PIBF level was obtained. RESULTS: The serum PIBF was 273 ng/ml after five days of oral micronized P. It increased further to 737 ng/ml despite taking six days of 200 mg mifepristone. CONCLUSIONS: The mechanism for inducing abortion by mifepristone does not seem to be related to decreasing serum levels of PIBF. This does not eliminate the possibility that the mechanism involves reducing the intracytoplasmic PIBF levels.

Serum levels of the progesterone induced blocking factor do not precipitously rise in women with gynecologic cancer in contrast to women exposed to progesterone.

PURPOSE: To determine if an immunomodulatory protein (progesterone induced blocking factor [PIBF]) that is progesterone induced and found in higher concentration during pregnancy is similarly found with increased levels in women with gynecologic cancers. MATERIALS AND METHODS: A newly developed enzyme linked immunoabsorbent assay (ELISA) assay was used to measure PIBF in the sera of six women with various gynecologic cancers and compare them to five controls (three with benign tumors and two having gynecologic procedures for non-tumors. RESULTS: The PIBF levels in women with gynecologic cancer did not rise precipitously as historical controls of women or men exposed to progesterone. The two highest PIBF levels of the 11 subjects were in women with gynecologic cancer. CONCLUSIONS: The data suggest that if PIBF helps cancer cells to evade immune surveillance, it probably operates through an intracytoplasmic presence. If an increase in sera PIBF could have been detected in women with gynecologic cancer, then this ELISA test could have been used to detect tumor recurrence. Future studies may concentrate on evaluating intracytoplasmic PIBF to possibly help determine which tumors may respond to progesterone antagonist receptors.

Lymphocyte immunotherapy can improve pregnancy outcome following embryo transfer (ET) in patients failing to conceive after two previous ET.

PURPOSE: To determine if lymphocyte immunotherapy (LIT) can improve the outcome after embryo transfer (ET) in women failing to have a live delivery after at least two previous attempts. METHODS: Women failing to deliver a live baby despite at least two previous ET cycles at Cooper Center for IVF irrespective of previous failed ET cycles in other centers were offered the option of lymphocyte immunotherapy prior to their next ET. They were subsequently matched to the very next woman having ET but in whom LIT was never offered or was refused. The matching was based on age, number of previous failed ET cycles, type of ET (fresh or frozen), and serum follicle stimulating hormone (FSH) level. RESULTS: The clinical and viable pregnancy rate was 70.3% and 51.3% for the LIT group vs 45.9% and 16.2% for the controls (p < .05). CONCLUSIONS: Lymphocyte immunotherapy may help improve outcome following ET in women with previous failures. The data should encourage a larger multicenter prospective study.

Matched control study of efficacy of lymphocyte immunotherapy in donor oocyte recipients to support or refute the concept of need for histocompatibility antigen sharing of the couple for benefits.

PURPOSE: To determine if lymphocyte immunotherapy (LIT) improves outcome in recalcitrant donor oocyte recipients. If LIT was found to be similarly effective in this group, the theory of shared maternal/paternal histocompatibility antigens would seem less plausible because the donor oocyte introduces another group of histocompatibility antigens. METHODS: Donor oocyte recipients with a history of failure to conceive despite at least two previous ETs using donor oocytes were given the option of having LIT. They were matched with the very next recipient who declined LIT therapy. Lymphocyte immunotherapy using the male partner's lymphocytes was given two weeks before transfer and twice more if pregnant. RESULTS: Only three controls delivered versus recipients treated with LIT. CONCLUSIONS: The fact that benefit from LIT extended to oocyte recipients challenges the concept that lymphocyte immunotherapy is most beneficial for couples sharing histocompatibility antigens.