A Cross-Reaction between β2-Microglobulin and κ-Light Chains

Abstract

Abstract Certain antisera to immunoglobulins containing κ-chains show the presence of antibodies that cross-react with β 2-microglobulin. This was most apparent with an antiserum made to highly purified F(ab) fragments of Fr II γ-globulin. These cross-reactive antibodies caused positive fluorescence and cytotoxicity reactions with a variety of cell types including T cells. These reactions were completely removed by absorption with highly purified κ-chains but not with λ-chains or λ immunoglobulins. β 2-microglobulin preparations also absorbed or inhibited the special cellular reactivities. Evidence was obtained that HLA-bound β 2-microglobulin was more efficient in this respect. The possibility is discussed that similar cross-reactive antibodies may have been involved in some previous studies of inhibition of T cell function by immunoglobulin antisera.