The peculiar-looking horseshoe crab is a key player in medical research thanks to a vital protein found in its blood.
Workers at the Wako Chemicals facility in Cape Charles, Va., as well as three other sites on the East Coast regularly capture horseshoe crabs to extract their pale blue blood to use in testing, Eastern Shore News reported.
"Basically, anything that comes into contact with the blood is tested using LAL [litmulus amebocyte lysate]," said site manager Christina Lecker.
The horseshoe crab's blood holds a protein that protects the animal from impurities and is used by researchers while testing medical instruments, implants and pharmaceuticals.
Amebocytes are the white blood cells that contain the protein, while lysate alludes to the extraction process. Because horseshoe crabs don't have an immune system, they need another way to isolate impurities especially in environments filled with bacteria.
Around 611,800 crabs were taken in 2012 for biomedical use, according to data from the Atlantic States Marine Fisheries Commission. Crabs are captured and brought into the lab, where workers extract a third of their blood. Two male crabs are usually needed to fill a bottle with blood, while the larger females can fill a bottle on their own.
The animals are taken from coastal waters under a biomedical permit and returned to their habitat after the blood is drawn.
"The crabs are returned within 48 hours," said Lecker, as quoted by Eastern Shore News.
After the blood-letting, crabs are marked with a small punch in the hole so they won't be taken in for extraction again until they have had time to molt and gain new, unmarked shells.
The precious protein in horseshoe crab blood is essentially refined until it can be used to ensure that medical equipment is bacteria-free.
Most patients likely don't know how much they owe to the unusual horseshoe crab, Lecker told Eastern Shore News.
"They have no idea how everything gets passed through the horseshoe crab test," she said.
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