The effect of specific cell inactivation on the cellular immune response to ferredoxin peptides

The effect of antigen suicide on numbers of cells binding defined antigenic determinants

Lymph node cells from guinea pigs immunized to oxidized ferredoxin (O-Fd) were treated in an antigen suicide procedure designed to inactivate lymphocytes binding the haptenic peptide determinants of the ferredoxin molecule. O-Fd-induced DNA synthesis and cells binding either peptide determinant were examined both before and after allowing suicide. The proliferative response to O-Fd and the number of determinant-binding cells were specifically and markedly decreased after antigen suicide.

Comparison of specificities of humoral and cellular immune response to haptens

In this study we induced humoral and cellular immunity to three isomers of aminosulfanilic and aminobenzoic acids and compared their respective specificities. These studies were facilated by using a new method for preferentially inducing a cellular immune response to haptens: the haptens were covalently coupled to mycobacteria and injected into animals in incomplete Freund's adjuvant. Humoral antibody was induced by coupling the same isomers to bovine serum albumin and injecting them into animals in complete Freund's adjuvant. Both groups of animals were examined for hapten-specific cellular immunity (migration inhibition factor, delayed skin tests) and for antibody response (passive hemolysin test). The results show that although both cell-mediated and humoral responses can discriminate the para, meta and ortho isomeric forms of the haptens used, the antibody response demonstrated much less cross-reactivity. The relevance of this finding to different requirement for B and T cells in antigenic recognition is discussed.