Naïve CSFE dye-labeled influenza hemagglutinin (HA) specific Clone 4 (CL-4) TCR tg CD8+ T cells were transferred into DTR recipients, followed sequentially at 24 hr intervals by low dose i.n. administration of DTx to selectively eliminate these two RDC subsets and then i.n. influenza infection. This evidence concerns the gene CD8A and influenza.