News Horseshoe crabs have a vital role in the development of a coronavirus vaccine. Here’s why September 22, 2020September 22, 2020Carol Motsinger, Greenville NewsComments Off on Horseshoe crabs have a vital role in the development of a coronavirus vaccine. Here’s why The horseshoe crab's fluorescent blue blood is its best line of defense against toxins. For 40 years, humans have harnessed that same power.