IL16 and infection: Similarly, we did not observe any different frequency of YFP-positive cells in the spleens of both WT and IL16 KO mice at day 18 post-infection (Fig 6D), but similar to day 16 post-infection, we observed an about 6.5-fold increase in the frequency of the cells with reactivating viruses for the IL16 KO mice (1/6,607) compared to that for the WT animals (1/43,251) at day 18 post-infection (Fig 6E), further supporting that IL16 blocks MHV68 reactivation from splenic latency.