Trypanosoma brucei Modifies the Tsetse Salivary Composition, Altering the Fly Feeding Behavior That Favors Parasite Transmission

• DOI: 10.1371/journal.ppat.1000926
• Publication Date: 2010-06-03T16:22:33Z
• Authors: Jan Van Den Abbeele; Guy Caljon; Karin De Ridder; Patrick De Baetse...; Marc Coosemans
• Keywords: Tsetse fly; Blood meal

Tsetse flies are the notorious transmitters of African trypanosomiasis, a disease caused by Trypanosoma parasite that affects humans and livestock on continent. Metacyclic infection rates in natural tsetse populations with brucei, including two human-pathogenic subspecies, very low, even epidemic situations. Therefore, infected fly/host contact frequency is key determinant transmission dynamics. As an obligate blood feeder, rely their complex salivary potion to inhibit host haemostatic reactions ensuring efficient feeding. The results this experimental study suggest might promote its through manipulation feeding behavior modifying saliva composition. Indeed, gland brucei-infected display significantly prolonged time, thereby enhancing likelihood infecting multiple hosts during process single meal cycle. Comparison major anti-haemostatic activities i.e. anti-platelet aggregation anti-coagulation activity these versus non-infected demonstrates significant suppression as result trypanosome-infection status. This effect was mainly related parasite-induced reduction gene transcription, resulting strong decrease protein content biological activities. Additionally, anti-thrombin inhibition thrombin-induced coagulation more severely hampered trypanosome infection. while naive strongly inhibited human thrombin coagulation, from T. showed enhanced thrombinase far less potent activity. These data clearly provide evidence for trypanosome-mediated modification composition drastically reduced potential performance which could lead increase vector/host field conditions.