Subinfectious hepatitis C virus exposures suppress T cell responses against subsequent acute infection

T cells specific for hepatitis C virus (HCV) have been reported in some individuals who have been repeatedly exposed to virus, yet have never had detectable HCV or HCV-specific antibodies. These findings suggest that T cells in these individuals may protect against infection by HCV. Barbara Rehermann and colleagues now test this assumption in a nonhuman primate study exposing animals to a very low dose of HCV.