Studies on Holothuria polii (Echinodermata) coelomocyte lysate. I. Hemolytic activity of coelomocyte hemolysins.

The Holothuria polii coelomocyte lysate contains two trypsin-resistant lytic proteins having different chemico-physical properties: a calcium dependent and heat-labile hemolysin that is probably a constitutive component of the coelomic fluid, and another calcium independent and heat-stable one that is released after immunological stimulation; it is therefore not detectable in natural conditions. The sphingomyelin seems to be the membrane receptor with which both hemolysins interact producing lysis.