ICAM1 and influenza: To further explore the cellular basis for the normal humoral response of ICAM-1/2-/- mice, reflected by normal recovery from sublethal PR8 infection (Figure 2B), normal viral clearance (Figure 2E), and full protection from a lethal homosubtypic viral challenge 40 days post primary infection (Figure 2D), we next dissected the accumulation of individual B and T cell subsets involved in antiviral humoral immunity in MedLNs that drain influenza infected lungs.