SURFACE IMMUNOGLOBULINS OF LYMPHOCYTES IN PLASMACYTOMA .5. EFFECT OF RNA-RICH EXTRACT FROM MOUSE PLASMACYTOMA MOPC 104E ON IMMUNE-RESPONSE

  • 1 January 1976
    • journal article
    • research article
    • Vol. 24  (2) , 357-367
Abstract
BALB/c mice with the MOPC-104-E plasmacytoma producing monoclonal IgM-.lambda. [immunoglobulin M-.lambda.], with antibody activity to .alpha.-1,3-dextran, had B [bone marrow-derived] lymphocytes with surface Ig''s with the immunochemical characteristics of 104-E IgM capable of binding .alpha.-1,3-dextran. RNA extracted from this plasmacytoma induced synthesis of such surface Ig''s on normal B lymphocytes in vitro and in vivo. Injection of 200 mg of MOPC 104-E RNA into normal mice 72 h prior to the administration of the antigen kept the immune response to dextran-S intact, but suppressed that to other antigens, such as DNP [dinitrophenol]-Ficoll and LPS [Escherichia coli lipopolysaccharide], T [thymus-derived) cell independent antigens, and SRBC [sheep red blood cells] and BSA [bovine serum albumin], which are T cell dependent. The effect of RNA was abolished by RNase, but not by pronase or DNase. RNA extracted from the LPC tumor (.gamma.2a-k without known antibody activity) significantly suppressed the immune response to dextran-S and other antigens in normal mice. Opposite effects of MOPC-104-E RNA on the response to specific and nonspecific antigens strengthen the hypothesis that the immune deficiency in plasmacytoma bearing mice is due to the conversion of normal surface Ig of a population of B lymphocytes to the idiotype of the respective myeloma globulin.