Fig. 8

ciMSC-EV treatment attenuates HI-induced deficits in oligodendrocyte maturation. Postnatal day 9 (P9) C57BL/6 mice were exposed to HI followed by i.n. administration of vehicle (0.9% NaCl, Veh) or ciMSC-EVs 1, 3, and 5 days after HI. Analyses were performed at P16. Oligodendrocyte density (a, b), oligodendrocyte proliferation (a, c), and oligodendrocyte maturation (d, e) were investigated in the cortex, striatum, and white matter via immunohistochemistry for the pan-oligodendrocyte marker Olig2 combined either with the proliferation marker Ki67 (a) or CC1, labeling mature oligodendrocytes (d). The amount of Olig2 single (b) and Olig2/Ki67 (c) or Olig2/CC1 (e) double-positive cells was quantified. mRNA expression analyses were performed for markers expressed by mature and myelinating oligodendrocytes in brain tissue lysates obtained from 160-µm-thick tissue sections at the striatal level (f). Beta-2 microglobulin served as housekeeping gene, and fold change values compared to sham animals were calculated (f). Representative images in a and d are derived from the indicated brain regions (scale bar: 50 µm). Examples for the white matter are obtained from the corpus callosum. *p < 0.05, **p < 0.01, ***p < 0.001, n = 8–10/group