Nerve growth factor in medium conditioned by embryonic chicken heart cells.

The present report demonstrates that embryonic chicken heart cells in culture release different nerve growth promoting factors to their culture medium, one which is biologically and immunologically similar to mouse gland beta NGF. Serum-free heart cell conditioned medium thus promoted neurite outgrowth from sympathetic and ciliary ganglia and supported survival of dissociated ciliary neurons. The addition of affinity purified antibodies against mouse beta NGF does substantially but not completely inhibit the fibre outgrowth from sympathetic ganglia, but does not to any extent diminish the effects on the parasympathetic neurons. The chicken NGF recovered from polyacrylamide gels after electrophoresis greatly enhanced sympathetic fibre outgrowth, an activity completely suppressive by anti-beta NGF antibodies. We conclude that a chicken NGF is being produced by the embryonic heart cells in culture, and that this factor may be produced also in the embryo to fulfill a role in heart innervation.