Enhanced DNA synthesis of human glial cells exposed to human leukocyte products

DNA synthesis was studied in primary glial cell cultures derived from adult human non-neoplastic and neoplastic brain tissues. Enhanced DNA synthesis occurred in 5/5 non-neoplastic astrocyte, one oligodendroglioma, and 2/5 astrocytoma cultures after exposure to medium containing 1.25-12.5% supernatant fluid (SF) from insoluble concanavalin A (Con A) stimulated unseparated or T lymphocyte-enriched human mononuclear leukocytes (MNL). Analyses of SF indicated that the presence of platelet-derived growth factor (PDGF) could not account for glial cell stimulation, and exposure to semi-purified interleukin-2 (IL-2) in amounts comparable to those in SF from Con A-stimulated MNL had no effect on glial cells. These data indicate that non-neoplastic astrocytes and other human glial cells are stimulated by products of human MNL.