BATF3 and infection: During the first 3 weeks post-infection the percentage of Th1 cells in the spleen increased quickly in both Batf3−/− and B6 mice and then decreased from 6 weeks post-infection, but there was no significant difference in Th1 cells responses between these two groups (F(7,15) = 0.01368, P = 0.9080) (Fig. 3a, b).