Comparative Immunology: Natural Hemolytic System of the Spiny Lobster, Panulirus argus

Summary A preliminary investigation of a naturally occurring hemolytic system in the West Indian spiny lobster, Panulirus argus, showed the hemolysin to have a certain degree of specificity for sheep erythrocytes and a natural hemagglutinin for various species of red blood cells. The resulting sigmoid shaped dose response curve of the reaction between sheep cells and increasing amounts of lobster hemolymph suggests that a multiple step mechanism may be involved as is common to mammalian hemolytic systems. Results of kinetics experiments involving the lysin are presented and apparently differ from those characteristic of the classical guinea pig complement system. The lobster hemolytic system was heat labile, inactivated by EDTA, and temperature-dependent; the latter indicating the possible existance of an enzymatic-type reaction. Attempts to potentiate lytic activity by addition of rabbit hemolysin were not successful. Results suggest that further work will be required to determine if the lobster hemolysin is in any way analogous to one or more components of the classical hemolytic complement system, either in makeup or mode of action. Additional studies should also focus on the hemagglutinin to elucidate the role it plays, if any, in this hemolytic system.