Identification of T cell peptides from C gamma 2ab involved in IgG2ab T cell-induced allotypic suppression. Relationship with the MHC haplotype of the suppressor T cell-donor Igha mice

Link to Pubmed [PMID] – 8335928

J. Immunol. 1993 Aug;151(3):1263-72

Using the algorithm of the peptidic self-model we selected, from the constant part of the IgG2ab polypeptidic heavy chain, four peptides susceptible to being recognized by the T cells of Igha mice that prevent IgG2ab expression. Among these four peptides, two were capable of enhancing in vivo this T cell activity of Igha mice almost as well as the whole IgG2ab allotype. One of these peptides, C gamma 2ab-248-263, located in the CH3 domain of IgG2ab, was effective in H-2d mice, while the other one, C gamma 2ab-103-118, located in the hinge region of IgG2ab, was efficient in H-2b mice. This demonstrates for the first time that this suppression involves the TCR of the effector cells and peptides derived from the allotype presented in the context of MHC molecules of the target cells, the presentation specificity being dependent on the MHC haplotype. The availability of these peptides will allow us to further understand the role of class I and/or class II MHC molecules in this suppression.