Modeling and immunohistochemical analysis of C6 glioma in vivo.

A reproducible in vivo model of C6 glioma was developed in Wistar rats. Analysis of histological preparations showed similar morphology of rat C6 glioma and human glioblastoma. The formation of a glial border at the periphery of the glioma, consisting of GFAP-positive reactive astrocytes, was shown by the immunohistochemical method. The border appeared on day 8 after implantation, astrogliosis was observed until animal death (day 28). Reactive astrocytes with branched processes surrounded not only the primary glioma focus, but also all sites of tumor invasion in the nervous tissue. Expression of EBA (blood-brain barrier marker) was disturbed and synthesis of AMVB1 (endothelial antigen) increased in neoplastic endotheliocytes, which suggested pronounced functional restructuring of the blood-tumor barrier in comparison with the blood-brain barrier. The phenomenon of predominant expression of GFAP and AMVB in the tumor tissue can be used for the development of systems for targeted drug transport into the tumor by means of appropriate antibodies.