Purification of a human alternative complement pathway inhibitor from hemolymph of larval fall armyworm (Spodoptera frugiperda).
Larval Spodoptera frugiperda hemolymph contains a specific inhibitor of the alternative pathway of human complement. This inhibitor was purified from larval hemolymph (HL) by 50% (NH4)2SO4 precipitation, DEAE-Sephacel chromatography and sequential gel-filtration on Bio-Gel 1.5m, 0.5m and Sephacryl S-200. Purified HL protein (Mr = 110,000) was composed of two Mr 55,000 polypeptide chains. Addition of purified HL protein to human complement resulted in a dose-dependent inhibition of RaRBC lysis and clumping of cells. The protein inhibitor provides a new tool for investigating the regulation of human alternative complement pathway.
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D003167:Complement Activation / Q000187:drug effects*; D003169:Complement Inactivator Proteins / Q000302:isolation & purification* / Q000494:pharmacology; D003170:Complement Pathway, Alternative / Q000187:drug effects*; D004591:Electrophoresis, Polyacrylamide Gel; D006458:Hemolymph / Q000032:analysis*; D006801:Humans; D007814:Larva; D008970:Molecular Weight; D009036:Moths
D000596:Amino Acids; D003169:Complement Inactivator Proteins