Figure 7.

B-1 cells engage complement-opsonized FeO-DEX via CR1/2, but not CR3. Spleen cells were pretreated in parallel with antagonistic anti-CD21/CD35 (CR1/2), anti-CD11b (CR3) and an according isotype control antibody (each 5 µg/mL), followed by incubation with differentially pretreated FeO-DEX (left untreated (w/o), pretreated with native or heat-inactivated (h.i.) serum) applied 45 min later. Frequencies of Cy5⁺ cells (upper panel) and MFI of Cy5 (lower panel) of B-2 (left panel) and B-1 (right panel) cells, identified as CD11b⁻CD19⁺ (B-2 cells) and CD11b⁺CD19⁺ (B-1 cells) were assessed 3 h after the onset of incubation with FeO-DEX (mean ± SEM of 3 experiments). Statistical differences * versus w/o and ^$ versus native serum group (treated with the same antibody), ⁺ versus isotype and ^#versus aCD21/35 (within same group) are indicated (one-way ANOVA, Tukey’s test). *^,+,# p < 0.05, **^,++,## p < 0.01, ***^,+++,###,$$$ p < 0.001.