A Cobra Venom Factor (Cvf)-Induced C3-Convertase Activity In The Hemolymph Of Galleria-Mellonella

A cobra venom factor (CVF)-induced C3 convertase has been generated from the hemolymph of Galleria mellonella . CVF was immobilized on Sepharose 4B and treated with cell-free hemolymph obtained from either unvaccinated G. mellonella larvae or larvae immunized with formalized Pseudomonas aeruginosa . The C3-cleaving activity was detected by the ability to cleave the alpha-chain of bovine C3 in a manner analogous to the CVF-induced mammalian C3 convertase, CVF, Bb. The insect-derived C3 convertase formed at 28°C but not at 37°C, then once formed was active at both 28°C and 37°C. EDTA did not inhibit the formation and action of the insect derived C3 cleaving activity.