Fig. 5

Microglia activation represented by Iba-1 and OX-42 immunofluorescence at 6 days post-CCD. a Compared to baseline, microglia (i.t.) pretreated with PBS and BMSC-lysate both induced tactile allodynia; BMSC-lysate pretreated microglia triggered fewer paw withdrawals compared with PBS pretreated microglia. b Iba-1 signal revealed moderate expression of resident microglia in both white and gray matter of the lumbar dorsal horn in sham rats; microglia exhibit a resting type morphology (inset). c Six days after CCD, microglia Iba-1 immunofluorescence increased significantly, and microglia exhibited activated phenotype (inset). The superficial laminae of the spinal dorsal horn (demarcated with green line) shows that microglia are a dominant population, consistent with their important role in nociceptive transmission and modulation. d Iba-1 immunoreactivity in the spinal cords was not altered by BMSC-treatment compared to the CCD control. e–g OX-42 signal also revealed that BMSC graft has no effect on microglia activation; e a resting type morphology (inset), f the dorsal horn from CCD animals, and g the dorsal horn from BMSC graft animals. **p < 0.01