Molecular crosstalk in host-parasite relationships: Schistosome- and leech-host interactions

The host-parasite relationship is based on subtle interplay between parasit e survival strategies and host defense mechanisms. In this context, parasit es often use the same or similar immune signaling molecules and/or molecula r mimicry to escape host immunosurveillance. Both processes represent an ad aptive strategy to ensure host immunocompatibility. This bidirectional comm unication between parasites and their hosts includes the renin-angiotensin, opioid and opiate systems. Here, Michel Salzet, Andre Capron and George St efano review recent work on the interaction of common signaling mechanisms in schistosomes, leeches and their host.