A ROLE FOR CELL-MIGRATION IN THE SEXUAL TRANSMISSION OF HIV-1

The issue of how human immunodeficiency virus-1 (HIV-1) enters the bod y following sexual contact has been the subject of considerable contro versy. Several possible routes for the initial infection have been sug gested [1-6], including the possibility that the transmission is media ted by HIV-1-infected lymphocytes or macrophages in serum and female g enital tract secretions, rather than by free virus, We recently report ed that HIV-1-infected, activated primary monocytes can migrate betwee n epithelial cells grown in confluent monolayer cultures in vitro [7]. We report here on experiments carried out in mice to test the hypothe sis that mononuclear blood cells are capable of migrating through inta ct epithelia, and thus of carrying a virus into an animal. We placed d ouble-stained, activated mononuclear blood cells into the vaginas of m ice; four hours later, numerous double-stained cells were observed in the connective tissue beneath the vaginal epithelium and the iliac lym ph nodes of the experimental mice, We speculate that such migration ma y be involved in the sexual transmission of HIV-1.