CHARACTERIZATION OF ES PRODUCTS INVOLVED IN WOUND INITIATION BY LUCILIA-CUPRINA LARVAE

Excretory/secretory (ES) products were collected up to 6 h after egg h atch and analysed by SDS-PAGE. The larvae produced a complex array of molecules, the pattern of which changed dramatically over the time of culture. When larvae were cultured on isolated sheep skin, skin degrad ation was found to occur immediately upon egg hatch with digestion of the available soluble skin molecules virtually complete within 6 h of culture, Proteolytic activity of the larval ES products was assessed b y gelatine substrate SDS-PAGE gels and revealed numerous secreted prot eases, the majority of which belong to the serine class of protease, S everal of these proteases appeared to be developmentally regulated inc luding a 28 kDa protease which was secreted only during the time of eg g hatch. Metabolic labelling experiments indicated that culture condit ions can influence the production of ES products with larvae cultured in the absence of sheep skin producing greater amounts and numbers of specific proteins.