PIBF: The Double Edged Sword. Pregnancy and Tumor
Article first published online: 29 MAR 2010
© 2010 John Wiley & Sons A/S
American Journal of Reproductive Immunology
Volume 64, Issue 2, pages 77–86, August 2010
How to Cite
Szekeres-Bartho, J. and Polgar, B. (2010), PIBF: The Double Edged Sword. Pregnancy and Tumor. American Journal of Reproductive Immunology, 64: 77–86. doi: 10.1111/j.1600-0897.2010.00833.x
- Issue published online: 6 JUL 2010
- Article first published online: 29 MAR 2010
- Submitted February 2, 2010; accepted February 5, 2010.
Citation Szekeres-Bartho J, Polgar B. PIBF: The Double Edged Sword. Pregnancy and Tumor. Am J Reprod Immunol 2010; 64: 77–86
Problem The role of progesterone-dependent immunomodulation in the maintenance of normal pregnancy.
Methods In vitro and in vivo data on the effect that progesterone and its mediator progesterone-induced blocking factor (PIBF) exert on the immune functions of pregnant women are reviewed, together with clinical findings.
Results Activated pregnancy lymphocytes express progesterone receptors, which enable progesterone to induce a protein called PIBF. PIBF increases Th2 type cytokine production by signaling via a novel type of IL-4 receptor and activating the Jak/STAT pathway. PIBF inhibits phosholipase A2, thus reduces prostaglandin synthesis. PIBF inhibits perforin release in human decidual lymphocytes and reduces the deleterious effect of high NK activity on murine pregnancy. PIBF production is a characteristic feature of normal human pregnancy, and its concentration is reduced in threatened pregnancies. PIBF mRNA and protein are expressed in a variety of malignant tumors. Inhibition of PIBF synthesis increases survival rates of leukemic mice.
Conclusion Progesterone-induced blocking factor is produced by pregnancy lymphocytes and also by malignant tumors. The PIBF-induced Th2-dominant immune response is favorable during pregnancy but might facilitate tumor growth by suppressing local antitumor immune responses.