Chemiluminescence by peripheral blood phagocytes from channel catfish: function of opsonin and temperature

The ability of the peripheral blood phagocytes from channel catfish, Ictalurus punctatus, to produce chemiluminescence (CL) following ingestion of the enteric pathogen Edwardsiella ictaluri was evaluated under a variety of opsonic and temperature conditions. The CL response was influenced by the concentration of immune serum used to opsonize the bacteria as well as the presence of nonspecific, heat labile opsonins. Peak light emissions were diminished and the time to peak response was increased with a reduction in temperature. Temperature-mediated changes in CL activity was accompanied by a corresponding change in intracellular killing. The addition of the metabolic inhibitors superoxide dismutase or sodium azide resulted in a reduction in CL and intracellular killing.