T cell clones of C57BL/6 origin which recognize porcine lactate dehydrogenase B (LDH‐BP) together with the Ab molecule were characterized in terms of fine specificity for both LDH‐B and self‐major histocompatibility complex determinants. Using antigen‐presenting cells from the Ab‐mutant strain B6.C‐H‐2bm12 (bm12), three clonotypes could be distinguished: the first responds to LDH‐BP + bm12, the second fails to respond and the third is alloreactive to bm12. The last clone exhibits additional alloreactivities to A molecules expressed in strains of H‐2 haplotypes f, r, s, u, w6, w7, w16, w17 and w23. All three clonotypes give identical response patterns to a panel of 17 different dehydrogenase enzymes, and react to the same tryptic peptide of LDH‐BP. Thus, these clones appear to recognize the same LDH‐B epitope together with at least 3 different determinants of the Ab molecule. The data suggest that alloreactivity is more closely related to T cell specificity for self‐major histocompatibility complex than to specificity for foreign antigen.
All Science Journal Classification (ASJC) codes
- Immunology and Allergy