Mechanism of Human Chorionic Gonadotrophinmediated Immunomodulation in Pregnancy

Amolak S Bansal; Shabana A Bora; Srdjan Saso; J Richard Smith; Mark R Johnson; Meen-Yau Thum


Expert Rev Clin Immunol. 2012;8(8):747-753. 

In This Article

Infertility & hCG

The authors have previously suggested that RM and recurrent failed IVF (RFIVF) may be due to significant maternal anti-embryo immune activity.[4,38] In both situations, impaired Treg cell function may be an important contributory factor.[39,40] In this regard, it is interesting that Schumacher et al. have confirmed the ability of hCG to stimulate the recruitment of Tregs to the fetal–maternal interface.[41] Thus, hCG may stimulate local changes in the balance of Th1, Th2 and Th17-type immunity that favor a Th2/Treg-type propregnancy phenotype. Furthermore, hCG may also directly, or indirectly via Th1 and Th17 cells, influence NK-cell activity, which we and others have previously reported to have a major negative impact on successful IVF.[42] It is presently unclear whether inadequate hCG release, hCG autoimmunity or disturbed hCG receptor function contribute to RM and RFIVF. In the setting of preeclampsia, inadequate placentation and tissue ischemia has been related to diminished hCG function, and interestingly this has been associated with reduced numbers of Tregs.[43]