In the absence of infection, anti-IFNAR1 treatment did not affect the differentiation of Tfh cell and GC B cell (Supplementary Fig. 4a, 4b); in the presence of LCMV infection, Tfh cell responses were enhanced, but pre-Tfh cell responses were decreased in anti-IFNAR1 treatment group compared with untreated group (Tfh cell, from 13.6 to 20.7%; pre-Tfh cell, from 31.9 to 26.4%), resulting in no significant difference in total Tfh cells between the two groups (Supplementary Fig. 4c); moreover, GC B-cell responses were slightly reduced in the immune-modulated group (Supplementary Fig. 4d). This evidence concerns the gene IFNAR1 and infection.