title: Evidence that the expression of progesterone-induced blocking factor by maternal T-lymphocytes is positively correlated with conception.
abstract: OBJECTIVE
  To compare the expression by T-lymphocytes of an immunomodulatory protein known as progesterone-induced blocking factor (PIBF) in conception versus non-conception cycles even when there has been definite fertilization and embryo formation.
  
  
  METHODS
  PIBF expression on T lymphocytes was measured using an immunohistochemical method with a PIBF-specific polyclonal antibody. These levels were determined in patients undergoing three types of therapy: non-in vitro fertilization (IVF), IVF-embryo transfer (ET), and frozen ET. Sera were drawn 12 days from ovulation in non-IVF cycles or 9 days after ET and were assayed for PIBF and beta human chorionic gondotropin. Comparison of the frequency of lymphocyte expression of PIBF in pregnant versus non-pregnant women were made.
  
  
  RESULTS
  PIBF was detected in 29.5% of non-pregnant women and 52.5% of pregnant women. There were no differences in PIBF levels by therapy used in non-pregnant cases or in the pregnant group.
  
  
  CONCLUSIONS
  These data are consistent with the hypothesis that maternal expression of PIBF in T-lymphocytes soon after trophoblast invasion may depend on successful implantation.
authors.affiliation: University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School at Camden, Cooper Hospital/University Medical Center, Department of Obstetrics and Gynecology, USA.
authors.forename: J H
authors.initials: JH
authors.lastname: Check
authors.forename: M
authors.initials: M
authors.lastname: Arwitz
authors.forename: J
authors.initials: J
authors.lastname: Gross
authors.forename: J
authors.initials: J
authors.lastname: Szekeres-Bartho
authors.forename: C H
authors.initials: CH
authors.lastname: Wu
mesh_terms: D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000097:blood; D010064:Embryo Implantation / Q000502:physiology*; D005260:Female; D005306:Fertilization / Q000502:physiology*; D006801:Humans; D011247:Pregnancy; D011257:Pregnancy Proteins / Q000096:biosynthesis*; D013491:Suppressor Factors, Immunologic; D013601:T-Lymphocytes / Q000378:metabolism*
chemical_list: D018997:Chorionic Gonadotropin, beta Subunit, Human; C110058:PIBF1 protein, human; D011257:Pregnancy Proteins; D013491:Suppressor Factors, Immunologic