Lifelong CMV infection in mice broadens mobilized TCR repertoire to third-party infection. Mus musculus strain:C57BL/6

Lifelong interactions between host and the ubiquitous and persistentcytomegalovirus (CMV) have been proposed to contribute to age-related decline in immunity. Unexpectedly, the OVA-specific CD8 TCRβ repertoire of old mice demonstrated that old MCMV-infected mice recruited many diverse clonotypes that afforded broad and often more efficient recognition of antigenic peptide variants. This stood in contrast to old control mice, that exhibited strong narrowing and homogenization of the elicited repertoire.