Osteopontin Augments M2 Microglia Response and Separates M1- and M2-Polarized Microglial Activation in Permanent Focal Cerebral Ischemia

Figure 2

OPN increases functional layering of microglia subtypes and influences the relative size of distinct infarct subareas. (a) Cresyl violet staining of the photothrombotic infarct. The infarct area could be subdivided into five zones according to distribution pattern of inflammatory cells: hypocellular infarct core (1), cell-rich infarct margin (2), demarcation zone (3), peri-infarct zone (4), and unaffected tissue (5). (b) The size of the evaluated infarct area shows a trend towards smaller infarcts, but no significant changes under OPN treatment. The infarct layers, especially those close to the core show significant changes. The size of the hypocellular core is significantly reduced post OPN and the infarct margin is proportionally larger. (c) Displays pseudocoloured images of exemplary photothrombotic infarcts. Sections were stained for Arg1 (yellow), CD206 (orange), YM1 (red), iNOS (green), Iba1 (blue), and vWF (purple). Adjacent sections of an OPN-treated animal (right column) and a control rat (left column). Scale bars represent 300 μm (c). All graphs show mean and SD; .

(a)

(b)

(c)