Surface component of primate thymus-derived lymphocytes related to a heavy chain variable region

Abstract

In a study designed to determine whether T cells of man and higher primates express a surface component related to the variable region of immunoglobulin heavy chain (VH), chickens were immunized with the purified VH fragment of a monoclonal Waldenström macroglobulin. The antibody preparation reacted with a mu chain determinant contained in the Fd fragment and with individual determinants characteristic of the orginal Waldenström protein. As estimated by immunofluorescence analysis, a subpopulation of normal human peripheral T cells (approximately 30%) bound the anti-VH antibody. B-Cell lymphoma lines grown in vitro, as well as some T-cell leukemia lines of the cotton-topped marmoset (Sagiunus oedipus), also bound the anti-VH antibody. The VH-bearing component of the T-cell line 70-N-2 was labeled biosynthetically by incorporation of [3H]leucine and was precipitated specifically by anti-VH antibody. This component was characterized by an apparent mass of 70,000 daltons as assessed by polyacrylamide gel electrophoresis under reducing conditions in buffers containing sodium dodecyl sulfate. These data provide direct support for the hypothesis that some T cells express and synthesize a component related to immunoglobulin heavy chains.