Immunologic abnormality of intrahepatic cholestasis of pregnancy.

PROBLEM

Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy risk because of the possibility of pre-term delivery and sudden intrauterine fetal death. Its pathogenesis is still under discussion.

METHOD OF STUDY

The analysis of the recent findings on the complex immunologic events that occur in ICP were performed.

RESULTS

In ICP, an increase of type 1 cytokine (TNF-alpha, IFN-gamma) associated with a decrease of type 2 cytokine (IL-4). The decreased production of the suppressor cytokine TGF-beta2 may increase the type 1 cytokine. Fas appeared to be increased and FasL appeared to be decreased in syncytiotrophoblasts of ICP. The human leukocyte antigen gene (HLA-G, E) in extravillous trophoblasts of ICP were significantly decreased.

CONCLUSION

Th1/Th2 cytokine balance and HLA play important roles in the tolerance and maintenance of pregnancy. ICP may be resulting from breach of the maternal fetal immune tolerance during pregnancy.