Antibody and T Cell Recognition of Select Ia Determinants Using the I-A Mutant B6.C-H-2 ^bm12

Abstract

Recognition of self Ia antigens is necessary for interactions between T cells, B cells, macrophages and certain soluble factors culminating in immune responsiveness to foreign antigens. Recognition of allogeneic Ia antigen has been purported to mimic self-recognition of Ia plus foreign antigen. A new approach to study the recognition of Ia is now possible due to the availability of the I-A mutant B6.C-H-2^bm12. Since bm12 mice have a gain-loss mutation in the gene encoding the A^b beta polypeptide, responses between bm12 and B6 recognize select Ia determinants corresponding to either the gain or loss specificities resulting from the mutation. Also resultant from this mutation are known differences between mutant and wild-type as detected by mixed lymphocyte responses (1) and Ir gene functions (2,3). In this report we investigate the recognition of Ia antigens in the humoral and T-cell responses between bm12 and B6 mice. This approach not only allows for comparisons between the antibody and T-cell responses to select Ia determinants, but may also give important insights into the recognition of self Ia antigens.