Conditioned media compositions having valuable biological activity are
obtained from cultures of immune cells from elasmobranch fishes. Methods are provided
for producing the conditioned media compositions. Conditioned media obtained using
epigonal cells from bonnethead sharks (Sphyrna tiburo) and lemon sharks
(Negaprion brevirostris) demonstrate strong anti-tumor activities. The conditioned
media compositions can be used for treating tumor proliferation and in immunosuppressive therapy.
