Figure 6.

Cx3cr1-haploinsufficiency results in attenuated proliferative response to IPC. A. WT and Cx3cr1-eGFP mice were subjected to a 15 minute tMCAO and 72 hours later mice were anesthetized, brain tissue was perfused and fixed and immunofluorescent microscopy and stereology was performed. The counts in wild-type (WT) mice show an increased number of Iba1⁺ cells in the ipsilateral hemicortex relative to the contralateral hemicortex (*p-value = 0.0247; N = 4 animals), whereas in the Cx3cr1-eGFP heterozygous animals the Iba1⁺ cell counts between the ipsilateral and contralateral hemicortices displayed no significant differences (p-value = 0.0899; N = 5 animals); and overall a genotype effect was observed between WT and Cx3cr1-eGFP heterozygous animals (##p-value = 0.0081, F = 9.50, DF_n = 1, DF_d = 14; ANOVA). Intriguingly, when the contralateral hemicortices were compared by genotype the Cx3cr1-eGFP heterozygous animals had significantly fewer microglia than WT animals (§p-value = 0.0123), and the ipsilateral hemicortices were not significantly different in post-hoc tests (p-value = 0.0596). B. When ex vivo flow cytometry was performed on Cx3cr1^CreER heterozygous animals 72 h after 15 min tMCAO, no difference was observed in the number of microglia collected from ipsilateral or contralateral hemispheres (t = 0.407, p-value = 0.7235, unpaired t-test; N = 3 experiments with 2–3 brains pooled per experiment).