We additionally show that after acute systemic infection with LCMV Armstrong virus, TSLP had a modest effect on primary CD8+ T-cell responses, with only a slight increase in Crlf2-/- cells in the spleen at day 8 p.i. Thus, TSLP can limit CD8+ T cell responses during primary viral infections, but the effect varied based on the tissue assessed and the type of viral infection. Here, CRLF2 is linked to viral infectious disease.