In vitro fertilization: angiogenic, proliferative, and apoptotic factors in the follicular fluid

The studies reported investigated the concentrations of angiogenic, proliferative, and apoptotic factors in the follicular fluid (FF) of individual follicles, aspirated from women undergoing controlled ovarian hyperstimulation using a long protocol for IVF treatment. Furthermore, the association of the concentrations of the preceding factors with oocyte maturity was studied. Vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), angiogenin, tissue polypeptide specific antigen (TPS), and soluble Fas (sFas) were all found in the FF of all follicles examined. Moreover, from the angiogenic factors only angiogenin concentrations, and from the apoptotic factors sFas concentrations (the soluble form expressing rather an antiapoptotic function), were positively associated with oocyte maturity, possibly indicating angiogenin's biological role beyond neovascularization and a lower apoptotic rate allowing oocytes to mature. Last, the abundant expression of TPS in FF may be indicative of intense cell proliferation, in cases of ovarian stimulation.