In some but not all chronic Hepatitis C patients, we found few hepatitis C virus (HCV)-specific CD8+ T cells that expressed CX3CR1 and also co-expressed GzmB as well as perforin (Fig. 7b,c and Supplementary Fig. 7A), whereas CX3CR1neg HCV-specific CD8+ T cells did not show GzmB or perforin expression (Fig. 7b,c). The gene discussed is PRF1; the disease is hepatitis A virus infection.