Figure 5

Toll-like receptor 2 deficiency delays evolution of ischemic brain lesion. (A) Representative low-magnification photomicrographs of cresyl violet stained brain sections of wild type (WT) and Toll-like receptor (TLR) 2−/− mice 3, 7 and 14 days after transient middle cerebral artery occlusion (MCAO). The ischemic area is emphasized by a black dashed line. (B) Significantly reduced direct stroke area in TLR2−/− mice 3 days after transient MCAO compared with WT mice. This was followed by marked lesion exacerbation in TLR2−/− mice 7 days after injury, while lesions in WT mice showed a reduction in size. The evolution of direct stroke area stagnated 14 days after injury, indicating significantly larger final lesion size in TLR2−/− mice compared with the WT group. (C) A smaller indirect stroke area in TLR2−/− mice compared with WT mice 3 days after transient MCAO. In contrast, 7 days after injury, indirect stroke area in the TLR2−/− group was larger compared with WT mice, and the same relationship was observed 14 days after ischemic injury. Values are expressed as mean ± SEM (n = 10, *P <0.05, **P <0.001).