Loss of anti-viral immunity by infection with a virus encoding a cross-reactive pathogenic epitope

Alex T Chen, Markus Cornberg, Stephanie Gras, Carole Guillonneau, Jamie Rossjohn, Andrew Trees, Sebastien Emonet, Juan C de la Torre, Raymond M Welsh, Liisa K Selin

Research output: Contribution to journalArticleResearchpeer-review

29 Citations (Scopus)

Abstract

T cell cross-reactivity between different strains of the same virus, between different members of the same virus group, and even between unrelated viruses is a common occurrence. We questioned here how an intervening infection with a virus containing a sub-dominant cross-reactive T cell epitope would affect protective immunity to a previously encountered virus. Pichinde virus (PV) and lymphocytic choriomeningitis virus (LCMV) encode subdominant cross-reactive NP(205-212) CD8 T cell epitopes sharing 6 of 8 amino acids, differing only in the MHC anchoring regions. These pMHC epitopes induce cross-reactive but non-identical T cell receptor (TCR) repertoires, and structural studies showed that the differing anchoring amino acids altered the conformation of the MHC landscape presented to the TCR. PV-immune mice receiving an intervening infection with wild type but not NP205-mutant LCMV developed severe immunopathology in the form of acute fatty necrosis on re-challenge with PV, and this pathology could be predicted by the ratio of NP205-specific to the normally immunodominant PV NP(38-45) -specific T cells. Thus, cross-reactive epitopes can exert pathogenic properties that compromise protective immunity by impairing more protective T cell responses.
Original languageEnglish
Article numbere1002633
Number of pages12
JournalPLoS Pathogens
Volume8
Issue number4
DOIs
Publication statusPublished - 2012

Cite this