Fig. 2: Construction and targeting validation of CD4mAb-conjugated mBMSC.

a Schematic illustration of the strategy for constructing CD4-mBMSC. b Confocal fluorescence images of mBMSC metabolically labeled with Ac₄ManNAz and reacted with DBCO-FAM (100 nM). Scale bars, 20 μm (n = 3 independent experiments). c Flow cytometry analysis of fluorescence intensity in N₃-mBMSC incubated with increasing concentrations of DBCO-CD4mAb-FITC (no gating applied; all cells included). d Confocal fluorescence images of N₃-mBMSC reacting with DBCO-CD4mAb-FITC fluorescent antibody (100 nM). Scale bars, 20 μm (n = 3 independent experiments). e Confocal fluorescence imaging of Dil-stained N₃-mBMSC or CD4-mBMSC (orange) co-cultured with CD4⁺ T cells for 6 h. Scale bars, 10 μm (n = 3 independent experiments). f Quantification of the ratio of CD4⁺ T cells bound to mBMSC per field. n = 10 randomly selected fields from three independent experiments. g In vivo fluorescence imaging acquired using an IVIS imaging system of DiD-stained mBMSC or CD4-mBMSC in IMQ-induced PO mice at 24 h, 72 h, and 96 h post intravenous injection. h, Quantification of fluorescence distribution in lungs, spleen, liver, and skin. n = 3 mice per group. Data are presented as means ± SD, and are analyzed by unpaired two-tailed t test (f) or two-way ANOVA followed by Tukey’s multiple comparisons test (h). Source data are provided as a Source Data file.