A NOVEL GENERATION OF CLONED HORSESHOE CRAB RECOMBINANT FACTOR C FOR DETECTION AND REMOVAL OF ENDOTOXIN

Abstract

The horseshoe crab, i(Carcinoscropius rotundicauda) Factor C cDNA (CrFC21) has been cloned into a shuttle baculoviral vector. The recombinant baculoviral DNA was then transfected into the insect cells for expression of recombinant Factor C. Recombinant Factor C was found to be immunoreactive and is capable of binding both free and bound/immobilized lipid A. It is enzymatically active when triggered by LPS. The rFC is probably of the two-chain form, being cleaved into the heavy and light chains after activation by Gram negative bacterial endotoxin. As low as 0.01 pg (0.001 ng/ml) of LPS was detectable by the rFC, thus, indicating its potentials as a novel generation of "limulus amoebocyte lysate".