(A and B). Thin cardiac sections from infarcted mice 3 days after MI were immunolabeled for PDPN (red) and CD68 (A), CD163 (B) (green), and nuclei (blue). PDPN-positive cells do not express CD68 and CD163, whereas CD68⁺ and CD163⁺ cells do not express PDPN. (C) Thin cardiac sections from saline control and (D) PDPN-neutralizing Ab–treated infarcted mouse hearts at 3 days after MI were indirectly immunolabeled with CD163 (red), CD68 (green), and nuclei (blue). Scars of treated animals (D) were characterized by a higher number of CD163⁺ cells compared with the saline control animals where the majority of the monocyte/macrophage population expressed CD68 (C). Quantitative analysis of the distribution of CD68 (C, graph) and CD163⁺ (D, graph) cells was performed (n = 3/group). Data are presented as mean ± SEM. *P < 0.05 saline control versus treated. Student’s t test was performed for analysis of differences between the groups (45). Flow cytometry analysis of the total resident monocyte/macrophage population isolated from the heart 3 days after MI confirmed the histology data. Mice treated with PDPN-neutralizing Ab were characterized by a higher percentage of CD163⁺ (G) and CD206⁺ (H) cells compared with the untreated animals where the monocyte/macrophage population was highly positive for CD68 (F). The total number of monocyte/macrophage recruited in the saline control and treated hearts was similar (E). Data are presented as mean ± SEM. ***P < 0.001 control versus treated (n = 3–4/group). Student’s t test was performed between the groups.