Two major areas of research were investigated over the last year. The first dealt with a study of the role of glycosylation in the synthesis, secretion and/or membrane expression of immunoglobulins in a variety of lymphoid cell populations. The antibiotic, tunicamycin, was used to inhibit the formation of N-acetylglucosamine-containing lipid intermediates that serve as sugar donors in the assembly of the oligosaccharide chains N-glycosidically linked to proteins and thus prevent glycosylation. Tunicamycin treatment of lymphocyte or plasma cell cultures resulted in the complete inhibition of radiolabeled sugar uptake into glycoproteins and also in a partial inhibition of protein synthesis. The results of these studies indicate that glycosylation is not a requisite event for either secretion or membrane expression of immunoglobulins. The addition of the carbohydrates appears, however, to facilitate the intracellular trafficking of the immunoglobulins. Similar to membrane immunoglobulins, HLA and H-2 antigens could be detected in the nonglycosylated form in the surfaces of tunicamycin-treated lymphocytes. Current studies are planned to assess the functional properties of the nonglycosylated immunoglobulins. A second major area of effort has been directed to the preparation of a xenogeneic antiserum reagent to murine B2-microglubion (B2M). Using a monoclonal antibody to H-2K, the H-2K antigen of the AKR lymphoma, RDM-4, was isolated in microgram amounts. Rabbits were immunized with the native H-2K or the isolated polypeptide chains (i.e., alpha chain of H-2K and mouse B2M). The antisera produced by the rabbits, particularly the anti-H-2K and anti-mouse B2M, show good reactivity in precipitating H-2 molecules from lysates of surface radiolabeled splenocytes. The availability of these high titered xeno-antiserum to murine B2M and H-2 now will facilitate studies on the biosynthesis of B2M and B2M-associated products in resting and activated lymphocyte cultures. Additionally, we hope to characterize and identify B2M-associated products with various T cell factor activities.