Solubilization of lymphocyte and thymocyte antigens by a reversible chemical modification

Abstract

The Weizmann Institute of Science, Rehovot Solubilization of lymphocyte and thymocyte antigens by a reversible chemical modificationAntigenic components of the particulate subcellular fraction from either rat thymocytes or lymph node lymphocytes can be obtained in a soluble form by reacting the membrane fraction with citraconic anhydride. As a result of citraconylation, 60-70 % of the proteins became soluble under physiological conditions and this soluble material was antigenically almost inactive. However, after decitraconylation at pH 5 and room temperature, the solubIe protein possessed antigenic activity (10-20 % of the original antigenic potency .of the lymphocytes) as tested by inhibition of the cytotoxic effect of heterologous anti-lymphocyte serum on lymphocytes and by other assays. The soluble antigenic components thus obtained from rat thymocytes induced the formation of anti-thymocyte serum when injected into rabbits. This antiserum was found to be active against thymocytes in the cytotoxic and opsonization assays and to suppress the rejection of skin allografts.

Detection of a cytokeratin determinant common to diverse epithelial cells by a broadly cross-reacting monoclonal antibody.

“…Preparation of keratin Prekeratin-enriched preparations, from bovine muzzle, containing the major epidermal polypeptides I -VII (Franke et al, 1978bSchiller et al, 1982) were obtained as described (Franke et al, 1981c Cellfusion and growth Three days after the last boost, spleens were removed and 100 x 106 cells from each individual spleen were fused with 20 x 106 NSO/1 myeloma line (Galfre and Milstein, 1981) kindly provided by C.Milstein (MRC, Cambridge, UK) using 41 7o polyethylene glycol 1500 (Serva, Heidelberg, FRG) as described previously (Eshhar et al, 1979). Following fusion, cells were distributed into six microplates (96 wells each) at a concentration of 5 x 10" viable cells/well.…”

A 135-kd membrane protein of intercellular adherens junctions.

“…Positively reacting mice (determined by RIA, see below) were injected again, 3 weeks after the challenge injection and 3 days later their spleens were removed and used for fusion. The preparation of hybridomas and their maintenance were carried out according to Eshhar et al (1979). The myeloma used for fusion was NSO (Galfre and Milstein, 1981), which were kindly supplied by Dr. Z.Eshhar from our Department.…”

Immunoglobulin mRNA stability varies during B lymphocyte differentiation.

“…In LPS-stimulated B lymphocytes there was a 25to 80-fold increase in ,t heavy chain mRNA (Yuan and Tucker, 1984;Lamson and Koshland, 1984;Berger, 1986). Pre-B and B cell lines have 10-100 times less A heavy chain mRNA than do plasmacytomas and hybridomas (Perry and Kelley, 1979;Eshhar et al, 1979;Perry et al, 1981;Nelson et al, 1983;. This variation in mRNA level could, in principle, result from different rates of transcription at the heavy chain locus, but apparently it does not.…”