ICAM1 and influenza: Taken together, our results suggest that although generated at lower rate inside ICAM-1/2-/- MedLN following influenza infection, and poor accumulation of this subset in the infected lungs on day 7 post infection, effector CD8+ T cells successfully accumulate in the infected airway mucosa and give rise to TRM CD8+ cells (Figure 5J), the major resident memory T cells that provide protection from secondary influenza challenges, in particular of heterosubtypic nature.