Disparate epitopes mediating protective heterologous immunity to unrelated viruses share peptide-MHC structural features recognized by cross-reactive T cells.Shen, Z.T., Nguyen, T.T., Daniels, K.A., Welsh, R.M., Stern, L.J.
(2013) J.Immunol. 191: 5139-5152
- PubMed: 24127554
- DOI: 10.4049/jimmunol.1300852
- Primary Citation of Related Structures:
- PubMed Abstract:
Closely related peptide epitopes can be recognized by the same T cells and contribute to the immune response against pathogens encoding those epitopes, but sometimes cross-reactive epitopes share little homology. The degree of structural homology req ...
Closely related peptide epitopes can be recognized by the same T cells and contribute to the immune response against pathogens encoding those epitopes, but sometimes cross-reactive epitopes share little homology. The degree of structural homology required for such disparate ligands to be recognized by cross-reactive TCRs remains unclear. In this study, we examined the mechanistic basis for cross-reactive T cell responses between epitopes from unrelated and pathogenic viruses, lymphocytic choriomeningitis virus (LCMV) and vaccinia virus. Our results show that the LCMV cross-reactive T cell response toward vaccinia virus is dominated by a shared asparagine residue, together with other shared structural elements conserved in the crystal structures of K(b)-VV-A11R and K(b)-LCMV-gp34. Based on analysis of the crystal structures and the specificity determinants for the cross-reactive T cell response, we were able to manipulate the degree of cross-reactivity of the T cell response, and to predict and generate a LCMV cross-reactive response toward a variant of a null OVA-derived peptide. These results indicate that protective heterologous immune responses can occur for disparate epitopes from unrelated viruses.
Department of Pathology, University of Massachusetts Medical School, Worcester, MA 01655.