Investigation of the effects of IL-1β, progesterone and HCG on extravillous trophoblast invasion BY transwell invasion method

Trophoblastic cell invasion is the main determinant for a successful pregnancy and is a process regulated by many hormones, growth factors and cytokines. The aim of this study is to compare the dose-dependent effects of hCG, progesterone and IL-1β on trophoblast invasion, to determine their effective doses, if any, and to reveal potential genetic factors of which expression levels can be measured and gene polymorphisms can be investigated in unexplained recurrent pregnancy loss. HTR8/SV neo cells were treated with hCG (10-20-40 IU/ml), progesterone (10-20-40 μM) or IL-1β (10-20-40 ng/ml) and transwell invasion analysis was applied. Stimulation of hCG and IL-1β increased the invasion of HTR-8/SVneo trophoblast cells within all doses. Progesterone stimulation had no significant effect on invasion of HTR-8/SVneo trophoblast cells. The doses that hCG and IL-1β contribute most to invasion of HTR-8/SVneo trophoblast cells; were found as 20 IU/ml for hCG and 20 ng/ml for IL-1β. When these doses were compared among themselves, the effect of hCG on the invasion of HTR-8/SVneo trophoblast cells was more pronounced than the effect of IL-1β. These findings support that; hCG and IL-1β have a dose-dependent effect in the regulation of trophoblast invasion, and this effect is more pronounced in hCG stimulation. In further studies, it is recommended to examine the gene polymorphism and the gene expression levels of hCG and IL-1β, rather than progesterone, in unexplained reccurent pregnancy loss. Key words: hCG, IL-1β, progesterone, trophoblast invasion