Figure 5. Preconditioning of B7-2 KO DCs with IL-10 restores their capacity to induce tolerance to myelin P0.

Adoptive transfer of DCs was performed in 5 mo old B7-2 KO NOD mice, as described in Fig. 4. Statistical analysis was made comparing B7-2 KO DC-IL-10 group vs. PBS (no AT) group in A-B. A. Mean clinical scores. *p < 0.0001 (n = 8–9). Grip strength measurements and sciatic nerve electrophysiology were performed at 12 weeks post AT. For grip strength, *p < 0.0001 (n = 8–9); #p < 0.0003 for all electrophysiologic parameters (DL, CV, dAMP) (n = 6–7). B. Immunologic studies at 12 wks post AT. Tolerance induction by B7-2 KO DC (IL-10) was associated with decreased splenocyte proliferation in response to P0 (180–199) or P0-ECD (20 µg/ml), increased percentages of Tregs (CD25⁺Foxp3⁺/CD4⁺) and B10 cells in the spleen but not in the Peri-LN. *p < 0.0002 (n = 4–5) for splenocyte proliferation; #p < 0.003 (n = 5–6) for splenic Tregs, and p < 0.003 (n = 6–7) for splenic B10 cells. C. Characterization of IL-10-preconditioned B7-2 KO DCs. Left panel: IL-10 pretreatment of B7-2 KO DCs led to altered immunophenotypic properties that mimicked those of WT DCs. Cells were gated based on CD11c staining, then analyzed for MHC class II, CD40, B7-1, PDL1 and PDL2 expression. Comparing B7-2 KO vs B7-2 KO DC-10, *p < 0.0002 for MHCII, CD40 and B7-1 (n = 4 each). Right panel: Improved capacity of B7-2 KO DCs to generate iTregs from sorted CD4⁺Foxp3 (eGFP) cells by IL-10 preconditioning [#p < 0.002 and *p < 0.0002 (n = 3 each)]. Experimental conditions were as described in Fig. 3C.