PRODUCTION AND SECRETION OF THIOREDOXIN FROM TRANSFORMED HUMAN TROPHOBLAST CELLS

Thioredoxin is a redox active protein which has been implicated in rep roductive processes. In this study we investigated the intracellular p roduction and extracellular secretion of placental thioredoxin by huma n cytotrophoblast cell lines which were used as in-vitro model systems . Results clearly demonstrated that thioredoxin is not only synthesize d by these cells but is also secreted and that while the intracellular thioredoxin is present only as a 12 kDa form, it would appear that th e extracellular thioredoxin is present in two forms, a predominant 12 kDa form accompanied by a lower amount of a 10 kDa form. The observed localization and possible secretion of thioredoxin at the fete-materna l interface suggest important roles for this protein during pregnancy. Intracellular thioredoxin may be involved in the prevention of cellul ar damage due to oxidative stress whereas extracellular thioredoxin ma y act to integrate the actions of the cytokine network operating at th e fete-maternal inter-face thereby assisting with implantation and the successful establishment of pregnancy.