FIG. 6.

Astroglial reaction in injured mouse brains at 7 days after closed head injury. Immunohistochemical staining of 10-μm-thick coronal brain was done using glial fibrillary acidic protein (GFAP) as a specific cell marker for astrocytes. Sham-operated wild-type (A and B), and Rag1^−/− mice (C and D), showed a similar baseline morphology of GFAP expression, with the classic feature of non-reactive astrocytes. In contrast, closed head injury induced reactive astrocytosis in the injured cortex of wild-type (E and F) and Rag1^−/− mice (G and H), with identical changes in morphology in both mouse strains by 7 days after trauma. The lower panels represent fivefold magnifications of the boxed areas of their respective upper panels (100×and 20×original magnifications).