Endotoxin detection--from limulus amebocyte lysate to recombinant factor C.

Area of Science:

• Biotechnology and Biomedical Diagnostics
• Microbiology and Immunology

Background:

• Gram-negative bacterial endotoxin (lipopolysaccharide, LPS) is a pyrogen causing fever and sepsis.
• The traditional limulus amebocyte lysate (LAL) test detects endotoxin but faces challenges with sensitivity, specificity, and horseshoe crab supply.
• Early and sensitive endotoxin detection is crucial for pharmaceutical quality assurance and preventing endotoxaemia.

Purpose of the Study:

• To develop an alternative, sensitive endotoxin detection method.
• To overcome limitations associated with the traditional LAL test and horseshoe crab dependency.
• To leverage recombinant technology for a stable and efficient endotoxin detection tool.

Main Methods:

• Genetic engineering was employed to produce recombinant Factor C (rFC) from the horseshoe crab coagulation cascade.
• The rFC was engineered as a proenzyme activated by trace levels of endotoxin.
• The rFC forms the basis of the PyroGene kit, a micro-enzymatic assay for high-throughput endotoxin screening.

Main Results:

• Recombinant Factor C (rFC), a 132 kDa proenzyme, was successfully produced.
• The rFC enables a novel micro-enzymatic diagnostic assay for sensitive endotoxin detection.
• The rFC-based PyroSense system provides checkpoints for biotechnology production lines.

Conclusions:

• Recombinant Factor C represents a significant advancement in endotoxin testing.
• This innovation provides a high-throughput, sensitive, and stable alternative to LAL assays.
• The development of rFC supports the quality assurance of biomedical products while conserving endangered horseshoe crabs.