Peripheral Circulation and Astrocytes Contribute to the MSC-Mediated Increase in IGF-1 Levels in the Infarct Cortex in a dMCAO Rat Model

Figure 7

NE+ neutrophils in the ischemia core cortex are not the main source of IGF-1. (a–d) In the infarct boundary zone of the ischemia group, immunohistological examination showed strong expression of neutrophil elastase (NE), a marker for neutrophils, mainly located inside the entire cerebral ischemia core cortex but not in the striatum or corpus callosum. No double staining of NE+/IGF-1 cells were found. (e–h) NE+ cell number was reduced in the infarct area 2 days after MSC transplantation. No double-stained NE+/IGF-1+ cells were observed in the transplantation group. (a, e) IGF-1 staining. (b, f) Neutrophil elastase staining. (c, g) DAPI nuclear staining. (d, h) Merged images of neutrophil elastase, IGF-1, and DAPI. Scale bar, 50 μm.