The use of Cytodex 3 microcarriers and reduced-serum media for the production of nerve growth promoters from chicken heart cells.

Microcarrier cell culture provides an efficient method for the production of cell products. Cytodex 3 microcarriers were used for the production of an active nerve growth-promoting substance from chicken heart fibroblasts (1 degree -4 degrees cultures). Such cells release into culture medium a factor which stimulates the growth of nerve fibres from explanted ciliary, sympathetic and spinal neurons. Furthermore, culture in low-serum or serum-free media reduces the presence of contaminating proteins and facilitates the production and biochemical analysis of this factor. A mixture of DME/F 10 was supplemented with either 10% (v/v) foetal calf serum (FCS), 0.5% FCS, a low molecular weight fraction of FCS, (MW less than 10,000; prepared by dialysis) or different hormones and growth factors. Cells cultured in medium supplemented with insulin (I, 1 microgram/ml), transferrin (T, 25 micrograms/ml), human serum albumin (HSA, 2 mg/ml) and fibronectin (F, 10 micrograms/ml) (ITAF) in combination with 0.5% FCS or a low molecular weight fraction of FCS progressed through the cell cycle with normal kinetics and maximum DNA synthesis was after 20 h. The results were similar to those obtained with a supplement of 10% FCS alone. Media supplemented with insulin, transferrin, fibronectin and HSA in combination with dexamethasone (200 ng/ml) or epidermal growth factor (10 ng/ml) did not promote cell proliferation to the same extent. The fibroblasts proliferated on Cytodex 3 at a rate similar to cells grown on cell culture plastic and produced sufficient amounts of nerve growth-promoting substance for biological analysis. Production of this factor was generally associated with cell proliferation.(ABSTRACT TRUNCATED AT 250 WORDS)