Progesterone as an immunomodulatory molecule

Int Immunopharmacol. 2001 Jun;1(6):1037-48. doi: 10.1016/s1567-5769(01)00035-2.


Increased progesterone sensitivity of pregnancy lymphocytes is due to activation-induced appearance of progesterone binding sites in the lymphocytes. Following recognition of fetally derived antigens gamma/delta TCR+ cells develop progesterone receptors. Progesterone binding results in the synthesis of a mediator protein named the progesterone-induced blocking factor (PIBF). PIBF by acting on the phospholipase A2 enzyme interferes with arachidonic acid metabolism, induces a Th2 biased immune response, and by controlling NK activity exerts an anti-abortive effect.

Publication types

  • Review

MeSH terms

  • Adjuvants, Immunologic / pharmacology
  • Adjuvants, Immunologic / physiology*
  • Animals
  • Female
  • Humans
  • Pregnancy
  • Pregnancy Proteins / physiology
  • Progesterone / pharmacology
  • Progesterone / physiology*
  • Suppressor Factors, Immunologic


  • Adjuvants, Immunologic
  • PIBF1 protein, human
  • Pregnancy Proteins
  • Suppressor Factors, Immunologic
  • Progesterone