This isn't specifically for coronavirus, from wikipedia > Amebocytes from the blood of L. polyphemus are used to make Limulus amebocyte lysate (LAL), which is

This isn't specifically for coronavirus, from wikipedia > Amebocytes from the blood of L. polyphemus are used to make Limulus amebocyte lysate (LAL), which is used for the detection of bacterial endotoxins in medical applications. There's a nice video here on it (3:22) https://www.youtube.com/watch?v=LgQZWSlLBnA https://www.youtube.com/watch?v=LgQZWSlLBnA