Fig. 5: IL10-producing M2 macrophages play a critical role in lenalidomide treatment.

a qRT-PCR analysis for expression of Il4, Il10, Il13, and Tgf-β in WT BMDMs with 25 nM lenalidomide treatment for 4 h (n = 3). b Concentration of IL10 in serum from vehicle or lenalidomide-treated WT EAE mice at day 17 (n = 6). c Concentration of IL10 in spleen and spinal cord from vehicle- or lenalidomide-treated WT EAE mice at day 17 (n = 6). d Immunostaining of mouse spinal cords from vehicle- and lenalidomide-treated WT EAE mice at day 16 using antibodies against CD68 (green) and IL10 (red). Scale bars: 150 μm (left), 50 μm (right). e Quantification of the percentage of CD68⁺ IL10⁺ cells among CD68⁺ cells from spinal cords in d. f, g Flow cytometry analysis of IL10⁺CD206⁺ cells in spleen and DLN from vehicle or lenalidomide-treated WT EAE mice at day 17. Representative FACS plots (f) and statistics from six mice per group (g) are shown. Cells are gated for CD206⁺ cells. h Western blotting analysis for expression of Ym1 in WT or IL10^−/− BMDMs with 25 nM lenalidomide treatment for 4 h. GAPDH was the loading control. i WT or IL10^−/− mice were immunized with MOG_35–55 and treated with lenalidomide (30 mg/kg, i.g.) or vehicle (0.9% CMC-Na, i.g.) at indicated time points (arrows). Mean clinical score is shown (n = 15 per group). j MBP and LFB staining of spinal cord from lenalidomide-treated WT or IL10^−/− EAE mice in i at day 15. Scale bars: 200 μm (upper), 100 μm (bottom). k WT mice were immunized with MOG_35–55 on day 0 and 3 × 10⁶ WT or IL10^−/− BMDMs treated with or without 25 nM lenalidomide for 4 h were injected intravenously into these mice at day 12. Mean clinical scores are shown (n = 8 per group). Data are presented as means ± SEM; *P < 0.05, **P < 0.01, ***P < 0.001