Thread: Friday Fish Factoid #4
03-07-2014, 04:51 PM #1
Friday Fish Factoid #4
0Horseshoe Crabs Save Lives... maybe even yours!
First of all I need to start you out with the fact that horseshoe crab blood is blue... like Aunt Beru's milk blue! And that is NOT the coolest bit of this factoid. This is due to the fact that their blood does not have hemoglobin (iron contained protein transport of oxygen) like the average vertebrate, but has hemocyanin (copper contained protein transport of oxygen).
Horseshoe crab blood is used as the major component in the LAL (Limulus Amebocyte Lysate) test to determine if injectable medications (and other blood contact medical devices) are safe to use. Specifically, the test is to determine if there is any gram-negative bacteria endotoxins (which make up the shell of the bacteria) in the compound. Endotoxins when injected into the blood stream can cause rapid fever and shock, quickly leading up to death.
Horseshoe crab blood does not have a white blood cell based immune system. Instead it has Amebocyte cells that when they encounter endotoxins release a clotting factor that makes a blood clot to isolate and contain the bacteria. This is what the LAL test is looking for... the clots.
Prior to the LAL test, drugs were tested by injection into a healthy rabbit to determine if the animal had a reaction.
For the LAL test... horseshoe crabs are caught, blood is collected and then released, to rebuild their blood supply again. There are varying reports on the exact figures, but the majority of crabs survive this bleeding process.
So the next time you are being injected, or visiting an aquarium, be sure to thank a horseshoe crab for being a blood donor!
Last edited by Trillianne; 03-07-2014 at 04:51 PM. Reason: prettying the format
03-10-2014, 06:51 PM #2
Cool! They are also the oldest unchanged form of life on this planet, I think.Life is tough, it's even tougher if you're stupid (John Wayne)
If you're not angry, you are not paying attention (Ralph Nader)
9 Tanks (2-29G QT) ranging from 150G to 10G for my 1/2 moon Beta
03-10-2014, 07:00 PM #3
03-10-2014, 07:11 PM #4
Woohoo for being crabby!55 g Goldfish Tank - 3 Fancies, 2 Comets
25 g Tropical Tank - Celestial Pearl Danio/Mixed