CD8A and influenza: Furthermore, transcription of the Cxcl10 gene, which encodes the principal CXCR3 ligand in influenza-infected lungs [24], was not affected by IL-4C (Fig. 4C), suggesting that IL-4-driven CXCR3 upregulation in both CD44hi and CD44low CD8 T cells caused such cells to accumulate in inflamed lungs.