Mitogen induced proliferation of isolated adult mouse Schwann cells

The proliferation of neonatal Schwann cells (SCs) in response to mitogenic agents has been well analyzed in vitro, but a limited range of mitogens have been defined. We investigated whether three identified neonatal SC mitogens [glial growth factor (GGF), platelet-derived growth factor BB (PDGF-BB), and basic fibroblast growth factor (bFGF)] are required to stimulate mitosis of adult SCs. Adult SCs were isolated from mouse sciatic nerves by mechanical and chemical dissociation, following three experimental steps: 1) culturing the dissociated cells for 24 hr in 10% FCS-F12 medium, 2) culturing these cells in serum-free medium for the next 48 hr, and 3) purifying adult SCs by differential adhesion. We describe a new method for preparation of SCs from peripheral nerves of adult mouse that provides 99.5% pure SCs populations at cell yields of greater than 3 x 10(3) cells/mg of starting nerve wet weight within 5 culture days. Although mitosis of SCs in culture in response to mitogens requires the presence of serum, the complex nature of serum renders difficult a complete analysis of mitogens required for SCs DNA synthesis, so we examined the proliferating response of adult SCs to GGF, PDGF-BB, and bFGF in serum-free medium. GGF alone had mitogenicity for adult SCs in a dose-dependent manner, and synergistic activation coupling with forskolin was not observed. Neither PDGF-BB nor bFGF was mitogenic for adult SCs when used alone or with forskolin.(ABSTRACT TRUNCATED AT 250 WORDS)