“…The piasma membrane of poiarized epithehal ceiis is divided by dght junctions into an apical domain, which is often covered by abundant microvilli and face the lumen of body cavides, and a basolaterai domain, facing adjacent ceiis, and die underiying basement membrane (for reviews, see (91,92)). MHC ciass II moiecuies have been found on the basoiateral surface and in intraceliular vesicies in tissue epithehai ceils of humans and rodents (93)(94)(95)(96)(97)(98)(99)(100)(101). The basolaterai membrane faces the vascuiar space, where the ciass II moiecuies may present andgen to emigradng T ceiis.…”