Occurrence of beta 2-microglobulin in mammalian lymphocytes and erythrocytes

Cell-associated beta 2-microglobulin (beta 2m) has been studied by quantitative techniques in lymphocytes and erythrocytes of guinea pig, rabbit, rat and man. beta 2m was solubilized by sonication followed by treatment with acid, deoxycholate or thiocyanate, and then determined by radioimmunoassay. The average number of beta 2m molecules per lymphocyte, estimated after acidification, varied between 0.89 X 10(5) and 7.1 X 10(5). Rat erythrocytes contained 3.0 X 10(3) molecules per cell, whereas no beta 2m was detected in red blood cells from the three other species. A relatively large part of beta 2m in the mammalian lymphocytes and in rat erythrocytes was present on the cell surface according to a radioimmunoassay procedure using anti-beta 2m antisera that had been absorbed with the blood cells analyzed.