9602001 Guyden The object of this research is to study the function of the thymic nurse cells (TNCs). Thymic nurse cells are specialized epithelial cells that contain thymocytes completely enclosed in intra-cytoplasmic vacuoles. The function of the interaction between TNCs and developing thymocytes. has not been determined, but is thought to be involved in development of specificity in the immune response. The laboratory of the PI has been able to immortalize TNCs, and these cells can internalize thymocytes in culture. These cells internalize double positive thymocytes, and a subset of these cells undergo apoptosis while another subset matures. The latter rescued population is MHC restricted. The proposed experiments will identify and isolate TNC specific monoclonal antibodies, and use these to clone the genes for target proteins. The investigator will use these antibodies to see if they will block thymic selection and differentiation. These studies are important to understand the function of these thymic nurse cells and their role in the development of the cells of the immune system derived from the thymus. ***
