Formation of specific antibodies and γ-globulin in vitro. A study of the synthetic ability of various tissues from rabbits immunized by different methods

Abstract

Incorporation of C14-amino acids into specific antibody and other gamma-globulin in vitro by tissue slices, from immunized animals, occurred at a constant rate for a few hours after a short lag period provided the cells were undamaged. After mild damage no incorporation into secreted proteins occurred although insoluble tissue proteins still became labeled. Under our conditions, procedures which broke up the cells completely prevented incorporation of added C14-amino acids into specific protein. Evidence is given that incorporation of the C14 -label into antibody is due to synthesis and secretion of antibody by the tissue slices. By comparing the rates of incorporation of C14-glycine or valine in vitro by different tissues taken from rabbits immunized by different routes, it was possible to assess the relative contributions of these tissues to overall synthesis of specific antibody and other gamma-globulin in the whole animal. Rabbits immunized by intramuscular injection of ovalbumin in Freund''s adjugant mixture synthesized most of their antibody in the local granuloma, but, after further intravenous injection of alum-precipitated antigen, the spleen, lung and bone marrow became important sites of synthesis. When ovalbumin or pneumococci, or both, were injected intravenously the bone marrow, or in some animals the lungs, made most of the antibody. In rabbits immunized simultaneously with 2 different antigens, tissues varied considerably in their ability to synthesize each kind of antibody. Tissues stimulated to produce specific antibody also produced increased amounts of other gamma-globulin which was not identified as specific antibody.