Colorless spherule cells and lysozyme contribute to innate immunological responses in the sea urchin Lytechinus variegatus, exposed to bacterial challenge.

The sea urchin Lytechinus variegatus is considered a good candidate for aquaculture, but bacterial diseases are a major challenge in culture conditions. The innate immunological defenses of L. variegatus to bacterial challenges were assessed through hematology parameters, in vitro phagocytosis, lysozyme activity and total plasma protein concentrations in cell-free coelomic fluid.