Investigating memory CD8 T cell-mediated immunopathology

Abstract Bystander memory CD8 T cells can respond to other pathogens independently of their cell receptors (TCRs). Current dogma is that these improve control unrelated acute infections via TCR independent, innate-like functions. Contrary this, we observed mice with the transgenic P14 specific for lymphocytic choriomeningitis virus (LCMV), or chimera mice, succumb a typically sublethal bacterial infection Listeria monocytogenes (Lm). However, reduced number transferred are less susceptible Lm, suggesting high frequency leads increased lethality Lm infection. At day 3 post infection, LCMV-experienced have significantly higher burdens in spleen and liver compared controls. Preliminary data also suggests certain cytokines may be involved this process. We investigating possible mechanisms bystander cell-mediated immunopathology. This work highlights not unequivocally protective but enhance susceptibility non-cognate infections. Supported by NIH grant, R01 AI38903.