Comparative levels of lysozyme activity in larvae and pupae of Galleria mellonella after particulate and soluble materials injection.

Using an assay system for lysozyme activity determination in which haemolymph was compared in activity to known standards, the quantitative shifts in the lysozyme activity level of larvae and pupae of Galleria mellonella, after particulate and soluble materials injection, were compared. The level of this activity in all injected larvae was higher fro that of pupae, but the immune response of pupae was more effective in all treatments when compared with activity in the non-injected controls. Furthermore, there was a significant higher level of lysozyme activity in pupae subjected to mechanical immunizing agents, except inversed pupae in which alternation in activity was not significantly different from activity in the corresponding nonexposed insects. Although the exact role of lysozyme in insect immunity is still uncertain, it is possible that this lysosomal enzyme may degrade the cell wall of susceptible parasites prior to being phagocytosed, and thereby act as a nonspecific inducible humoral defence molecule.