Fluorescence Immunohistochemistry The complex process mediating brain tissue recovery after traumatic brain injury remains unclear. Through the development of a new multi‐phenotyping fluorescence immunohistochemistry (MP‐IHC) method using up to 10 relevant biomarkers of neuroplasticity and angiogenesis, tissue remodeling after controlled cortical impact (CCI) to the brain can be studied in a comprehensive manner. Rat brains were collected seven days after CCI injury, then fixed and cryopreserved, followed by fluorescence immunostaining. Distribution of resident cell types (neural progenitors, immature neurons, specific mature neuronal phenotypes, astrocytes, microglia, and endothelial cells) in response to CCI was characterized using 10‐color fluorescence microscopy. At 7 days after CCI, there was extensive loss of all neuronal and astroglial cell phenotypes in all cortical layers at the injury site. Dedifferentiated astrocytes and activated microglia formed a prominent glial scar around the injury site, extending down to the corpus callosum. Some neovascularization could also be seen in the brain tissue surrounding the injury site. In addition, there was limited recruitment of new neurons from both the ipsilateral (injured) and contralateral (non‐injured) sides of CCI injured brain. Our novel multiplex fluorescence immunohistochemical method using relevant biomarkers of brain neuroplasticity and angiogenesis reveals a very dynamic and complex brain tissue remodeling at 7 days after CCI. This method has the potential to be a very useful diagnostic tool for determining the extent of brain tissue damage and repair after different types of traumatic brain injury.
Last updated December 14, 2012