FIG. 5.

Comparable upregulation of activation markers by stimulated DCs. E. coli bacteria were opsonized with serum from wild-type (WT), RAG1^−/−, or C3^−/− mice or with RAG1^−/− serum depleted of complement by heat inactivation (HI). Opsonized E. coli bacteria were then added to BM-DCs. After 6 and 24 h, DCs were stained and analyzed by flow cytometry for surface display of CD40, CD86, and class II MHC or using isotype control antibodies. Opsonized E. coli bacteria induce potent DC activation regardless of the serum used.