We have an Angry Crab restaurant down the street from our home. It’s loads of fun! You get great seafood and just throw all of it on the table and start cracking, slurping and sucking, with butter and juices running down your arms to your elbows and all over your face. We destroy these crabs! No wonder they are angry.
I discovered another angry crab recently. I came across an great article about harvesting, in this case bleeding, horseshoe crabs. Turns out that the blue blood of horseshoe crabs is the best way we have to detect dangerous gram negative bacteria. These bad germs could turn up in insulin, on medical devices like scalpels, IV sets, or even on your knee or hip replacement!
The magical substance that does the actual detecting is called LAL for short, or Limulus Amoebocyte Lysate. Limulus polyphemus for the species of horseshoe crab, Amebocytes are cells in the crab’s blood, and Lysate, as you may recall is the result of lysing or breaking the integrity of the cell. You can imagine that this stuff is not cheap. Estimates put the cost of this blue blood lysate at $15,000 per quart and a single LAL test kit costs about $1000.
To their credit, the six U.S.companies only take about one-third of the blood from each crab and return it to the ocean, where it is assumed they recover, much like we would after donating blood. We don’t donate 1/3 of our blood though! Of the 500,000 crabs that are bled each year, over 50,000 perish and there is also concern that fertility is diminished. Horseshoe crab populations are dwindling. As if marine species don’t have enough problems with rising temperatures, disappearing beaches, and floating plastic debris, this species is hunted for its blood. Horseshoe crabs are also eaten, well at least, the roe is. It’s quite a delicacy in Thailand, for instance.
There is hope on the horizon. Scientists reasoned that if the specific molecule that was responsible for detecting the gram negative toxins was isolated, and also identify the gene responsible for producing this molecule, we could mass produce an effective product without relying on crabs. A couple of scientists, Ding and Ho, did just that. Big Pharma was slow to adopt the new technique, however, and there are few companies that sell the recombinant Factor C kits. Factor C kits were approved in Europe in 2016 and Eli Lilly, one of the pioneers of recombinant DNA insulin, is lobbying hard for approval here in the U.S. Perhaps horseshoe crabs, a species that’s been around since dinosaurs walked the Earth, will survive another millennium or more!