application s abstract): The immediate goal of the candidate, Amy E. Rullkoetter, DVM, is to complete a mentored training program in retrovirus pathogenesis research which will culminate in both the Ph.D. degree and the opportunity for continued postdoctoral study. Dr. Rullkoetter's long-term goal is to become a principal investigator employing state-of-the-art methodologies to investigate the pathogenesis of HIV. The research training program will be conducted in the Retrovirus Research Laboratory at Colorado State University, under the guidance of the sponsor Dr. Edward A. Hoover. The candidate's program plan consists of laboratory training in contemporary molecular techniques and research methods, applied to an animal model of AIDS. The applicant proposes to use an established feline immunodeficiency virus (FIV) model of transvaginal lentivirus infection to investigate the initial events in mucosal lentivirus infection. The three specific aims addressed are: (1) to determine whether FIV crosses the intact vaginal and/or cervical mucous membrane by transcytosis in vivo; (2) to determine whether FIV infects cells within the epithelial layer as it traverses the vaginal and/or cervical mucous membrane ex vivo; and (3) to track the pathway of FIV transmucosal infection in vivo and assess the impact of hormonal balance on this process. The results of these studies may help elucidate the mechanisms of transmucosal lentivirus infection and thus aid in its intervention.