ABSTRACT
Infection with Schistosoma mansoni causes hepatic granuloma formation and fibrosis in response to parasite eggs. The present work localized the leucine aminopeptidase [LAP] in S. mansoni eggs and in liver tissue sections from infected mice. Fresh eggs and livers obtained from infected hamsters were processed and stained with the L-leucine-7-amino-trifluoro-methylcoumarin specific substrate. The L-argnine-7-amino-trifluoro-methylcoumarin and bestatin [leucine aminopeptidase inhibitor] were used to test the LAP substrate specificity and reactivity. The staining pattern for that enzyme in the egg and liver tissue reflects that the leucine aminopeptidase is a major egg constituent distributed in nearly all the egg except the spine. The control substrates confirmed the substrate broad specificity of LAP. It was concluded that the LAP enzyme is a major egg antigen and the target antigen for the antipathology vaccine development studies