Definition of a cell clone with astroglial characteristics derived from a chemically induced rabbit brain glioma.

Three-month-old rabbits were started on a fortnightly schedule of intravenous injections of N-methyl-N-nitrosourea. All but two of the central nervous system tumors induced in this manner were propagated in culture as permanent cell lines. On the 76RB-G-414-H line established from a grade 2 astrocytoma of this series of neoplasms, a cloning procedure was carried out using a laser microbeam. The clonal line originated in this way has been maintained in long-term culture and given the 76/RB-G-414-H-C designation. The cells of the clone display invariably a bipolar or multipolar configuration with long processes. Intermediate filaments are common and even abundant in some cells. Positivity for S-100 and GFA proteins is a regular finding in these cells. In addition, dibutyryl cyclic adenosine monophosphate treatment reduces cell division and stimulates cell process formation of these cells. Thus, it appears that we succeeded in establishing in vitro and maintaining in long-term culture a clone of tumor cells with astrocytic characteristics.