Figure 1.

LV delivery of mammalian-compatible engineered ChABC under a PGK promoter leads to large-scale CSPG digestion in the adult mammalian spinal cord; comparison of bacterial ChABC enzyme versus LV-ChABC. A, Immunoblotting for C-4-S stubs was used to compare GAG digestion in the injury epicenter (T10) of conventional ChABC enzyme-treated and LV-ChABC-treated cords at 3 d and 2 weeks following spinal contusion. Lumbar (L2) and cervical (C4) segments as well as brain cortex were also blotted to visualize the spread of GAG digestion at 2 weeks postinjury. B, For ChABC and LV-ChABC injury epicenter comparisons, results are mean density values + SEM; n = 3 cords; *p < 0.05; ***p < 0.001, one-way ANOVA and Bonferroni's multiple-comparison test. For the lumbar, cervical, and cortex, each lane is a pool of extracts derived from three animals. C–F, Immunohistochemistry in sagittal sections through the uninjured (C, D) or the injured (E, F) thoracic spinal cord showing the C-4-S (green) digestion pattern at 8 weeks postinjection with or without contusion injury. In uninjured spinal cords, weak C-4-S immunoreactivity restricted to the injection zone was apparent 8 weeks following injection of bacterial ChABC (C), compared with intense and widespread C-4-S immunoreactivity with LV-ChABC injection (D). Abundant CSPG digestion was also observed at the injury epicenter 8 weeks following contusion and LV-ChABC injection, and the lesion site appeared to be associated with numerous tissue bridges (F). By comparison, the injury epicenter following intraspinal injection of conventional ChABC enzyme contained lower levels of digested CSPGs at 8 weeks postinjury and the epicenter had developed into a large cavity (E). These data suggest that large-scale CSPG digestion achieved by LV-ChABC may have a neuroprotective effect. Scale bar: (in F) C–F, 1 mm.