Discussion on the Differences Between Limulus Reagent and Recombinant Factor C Reagent
Keywords:
Endotoxin, Limulus amebocyte lysate, Recombinant Factor C, Bacterial endotoxins testAbstract
Limulus amebocyte lysate (LAL) is widely used for the detection of endotoxin, one of the most potent pyrogens. Recent studies revealed the mechanism of activation of Factor C and Factor B, endotoxin-binding proteins in the LAL cascade. It is well-known that Factor C is the first factor to bind endotoxin aggregates. The second coagulation factor, Factor B is important to achieve specificity of LAL to endotoxin because activated Factor C on endotoxin aggregates are essential for its activation. The endotoxin-specific signal is amplified after Factor B activation in LAL. On the other hand, recombinant Factor C reagents only rely on the specificity of Factor C to endotoxin and amplify the trypsin-like activity of activated Factor C that may not be specific to endotoxin. This mechanism seems to be not as specific to endotoxin as LAL. More evaluation and improvement are necessary for recombinant reagents for endotoxin measurement as a safety test.
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