Microglia are the resident macrophages of the CNS and are activated in response tobrain injuries, including preterm brain injuries.62, –64 GMH inducesmicroglia-mediated inflammatory responses and oxidative stress that damage thetissue surrounding the injury and the white matter.65, , –68 Treatments that reduceinflammation can enhance myelination and neurological recovery afterintraventricular hemorrhage.69 Multiple inflammatory chemokines and mediators such as Ccl2,Ccl4, Ccl6, Tlr5,Mmp8, and Spp1 were upregulated 72 hours afterGMH, likely reflecting the activation of microglia. Here, TLR5 is linked to hemorrhage.