Lymphocyte Associated beta2-Microglobulin Studied by Crossed Radioimmunoelectrophoresis

Abstract

A sensitive radioimmunoelectrophoretic assay was employed in the study of .beta.2-microglobulin (.beta.2m) from human blood lymphocytes, allowing the detection of 2.5 pmol of .beta.2m corresponding to 3 .times. 106 lymphocytes. The intrinsic (amphiphilic) membrane proteins were solubilized and examined in crossed immunoelectrophoresis against rabbit antisera in the presence of non-ionic detergent. The .beta.2m-associated precipitate was traced by post-electrophoretic incubation with 125I-labeled antibodies to .beta.2m and autoradiography. A polyspecific rabbit antiserum to human lymphoid cells retained its capacity to precipitate lymphocyte .beta.2m 4fter absorption with isolated .beta.2m (on an immunosorbent column), showing that lymphocyte B2m is complexed to other molecules. No free .beta.2m was found on lymphocytes when examined against the absorbed antiserum to human lymphoid cells in an intermediate gel and anti-.beta.2m in a reference gel.