TIE1 and ovarian hyperstimulation syndrome: The goals of this study were twofold: (i) to examine the role of Tie1 in the pathophysiology of OHSS and (ii) to elucidate its mechanism of action using in vitro and in vivo models of the disease, which included human follicular fluid specimens and an experimentally induced rat model of the disease, as well as human primary granulosa cells and SVOG cells, a human granulosa–lutein cell line, both of which were treated with a high dose of hCG to mimic the cellular events occurring during IVF.