Regulation of the immune response. VI. Inability of F(ab') 2 antibody to terminate established immune responses and its ability to interfere with IgG antibody-mediated immunosuppression.

Abstract

Intact IgG antibody can terminate established immune responses, whereas F(ab′)(2) antibody cannot do so. The difference between the two antibodies appears to be qualitative. F(ab′)(2) antibody, but not pepsin-digested normal serum, can interfere with the suppression and termination of immune responses induced by intact IgG antibody. These results are discussed in terms of the tripartite inactivation model.