Fig. 3: Identification of CD248 as the target antigen for CAR-T cells against F-Act.

a Triple IF staining for periostin (green) and CD248 (red) in the peri-infarct zone of the hearts of C57BL/6J WT mice 0, 7, 14, 21, and 28 days after MI surgery. Nuclei were stained blue. Scale bar = 100 μm. Quantification of the periostin⁺CD248⁺ cell to DAPI ratio in each HPF. n = 5 mice at each time point after MI. Triple IF staining of periostin, αSMA, COMP (stained green), and CD248 (stained red) in the hearts of MI mouses (b) and a patient with ischemic cardiomyopathy (c). Nuclei were stained blue. Scale bar =100 μm. IF staining of mouse heart was repeated in heart sections from 5 independent mice, while IF of human heart was repeated 5 times in heart sections from one patient with ischemic cardiomyopathy, yielding similar results. d Flow cytometry of cells isolated from hearts of C57BL/6 J WT mouses and Pdgfra-CRE:tdTomato mice. Total cardiac fibroblasts were lineage traced by pdgfrα. Quantification of the CD248⁺ cell ratio in live cells, pdgfrα⁺ fibroblast ratio in CD248⁺ cells, CD248⁺ cell ratio in pdgfrα⁺ fibroblasts, periostin⁺CD248⁺ cell ratio in pdgfrα⁺ fibroblasts, CD248⁺ cell ratio in periostin⁺ activated fibroblasts, and periostin⁺ activated fibroblasts in CD248⁺ cells. n = 5 mice at each time point after MI. a, d Data are the mean ± SEM and p-values are displayed in the bar charts, one-way ANOVA followed by Tukey’s multiple comparisons tests. Source data are provided as a Source Data file.