Furthermore, we observed that C3 does not play a costimulatory role on lung mDCs as the expression of maturation markers (Fig. 1E,F, Fig. 4E and Fig. 5A–C) and the priming ability of mDCs from the dLN were comparable between WT and C3−/− mice during influenza infection (Fig. 1G). The gene discussed is C3; the disease is influenza.