CCL4 and infection: Although there was more variability in the levels of cytokines induced by the different viruses in different donors, we could detect significant upregulation of CCL3/MIP-1α, CCL4/MIP-1β, IL-6, and CXCL10/IP-10 by two or more viruses (Fig. 1b), consistent with previous reports.12,31,32 Transcription of hundreds of genes was significantly altered after infection.