FIG. 3.

Inability to recruit Rab27a to complement-facilitated phagosomes. DCs from MHC class II-EGFP mice were incubated with DsRed-E. coli opsonized with indicated sera to allow uptake. At 2 hours postinfection, DCs were collected and stained for Rab27a. Phagosomes induced by uptake of E. coli bound to wild-type or C3^−/− serum showed strong recruitment of Rab27a (A and C), whereas phagosomes formed by E. coli opsonized with RAG^−/− serum did not show recruitment of Rab27a (B). Heat-inactivated (HI) RAG^−/− serum did not promote E. coli phagocytosis and served as a negative control for Rab27a staining (D).