Crab blood remains vital in America for drug and vaccine-making
Fishermen catch hundreds of horseshoe crabs as they crawl onto shore to mate, every April in South Carolina. An American pharmaceutical company, in Charleston the crabs are transported to labs owned by Charles River. There they are strapped and, still alive, drained of about a third of their blue-coloured blood to steel countertops. Then they are returned to the ocean. For America’s biomedical industry this liquid is vital. For as much as $15,000 a litre of it goes. On the horseshoe crab parts of modern medicine unusually have been reliant. An extract that detects endotoxin, a nasty and sometimes fatal chemical produced by certain bacteria, its blood is the only known natural source of limulus amebocyte lysate (lal). To ensure the safety of medicines and implanted devices drug firms use antibiotics, anti-cancer drugs, heart stents, insulin and vaccines. By giving a visual signal of unwanted contamination the immune cells in the crab’s blood clot around toxic bacteria. Demand...