The immunomodulatory factors of bloodfeeding arthropod saliva

There are potent immunomodulators in saliva of the bloodfeeding arthropods which transmit many of the world's most serious diseases that may benefit t he arthropod by preventing the vertebrate host from becoming sensitized to the saliva. In addition, saliva can enhance transmission of parasites/patho gens by arthropods. As a result, vaccines that target the arthropod (e.g. s alivary immunomodulators) should be considered as one component of multisub unit vaccines against arthropod-borne parasites/pathogens. Indeed, since va ccines against the pathogens themselves are often not fully protective, vac cines that target several facets of the life cycle of the pathogen may be t he most effective at controlling disease transmission. This review covers k nown immunomodulatory factors in arthropod vector saliva, focusing mainly o n sandflies and ixodid ticks.