To determine whether the increased frequency of TVM cells in the lungs of Aiolos-deficient mice (Fig. 6e) provides enhanced protection against viral infection, we infected WT and Ikzf3−/− mice with PR8 followed by FTY720 or saline administration at 1 d.p.i. This was done to limit our analysis to effects of the early-responding TVM observed within the first day following infection as FTY720 treatment prevents later migration of lymphocytes to the site (Fig. 7e). Here, IKZF3 is linked to infection.