Pathogenesis of endometriosis--current research.

Proliferative, secretory and menstrual endometrial cells of both the stroma and epithelium adhere to intact peritoneal mesothelium and mesothelial monolayers. Endometrial attachment to the mesothelium appears to occur rapidly (within 1 h) and transmesothelial invasion occurs between 1 and 18-24 h. These results demonstrate that the mesothelium is not a 'no-stick' surface and indicates that molecules present at the surface of the mesothelium are involved in the pathogenesis of the early endometriotic lesion. The inhibition of endometrial cell adherence to peritoneal mesothelium by hyaluronidase indicates that CD44-hyaluronan binding is at least one of the mechanisms involved in the pathogenesis of endometriosis. We believe that investigation of mesothelial cell adhesion molecules is central to understanding the pathogenesis of endometriosis.