Jeak Ling Ding
senior researcher Dept Biological Sciences, National University of Singapore
Title: Endotoxin Diagnostics and Depyrogenation - from Cloning to Biomedical Applications
Biography
Biography: Jeak Ling Ding
Abstract
During Gram-negative bacterial infection, endotoxin (aka lipopolysaccharide, LPS) released from the outer membrane of the gram-negative bacteria, interacts with host sensor/receptor proteins to drive inflammation and pyrogenic reaction. In severe persistent infections, excessive LPS induces septic shock. The ubiquity of endotoxin poses a threat to the biotechnology, pharmaceutical and healthcare industries. The quality assurance for injectable drugs and medical devices, to be free of endotoxin, started with the slow, less efï¬cient and expensive pyrogen test using rabbits. In the mid-1970s, the US Food and Drug Administration (FDA) approved the Limulus amoebocyte lysate (LAL) for testing endotoxin contamination. However, the LAL test requires the harvesting and bleeding of the horseshoe crab. Problems with the speciï¬city of LAL to endotoxin and the threats on horseshoe crab extinction called for an alternative more reliable endotoxin test. This paper reviews biotechnology efforts on cloning and expression of recombinant Factor C (rFC), the endotoxin-inducible sensor in LAL, which establishes a synthetic rapid diagnostic test for endotoxin. The rFC-based PyroGene® is US FDA-approved. Based on the identified LPS-binding motifs in rFC, we synthesized short peptides (sushi domains) and innovated LPS-removal system to depyrogenate parenteral fluids.