Advanced search
Start date

Functional study of the cell signaling pathways involved in the immune response of the Amblyomma aureolatum tick against Rickettsia rickettsii infection

Grant number: 16/19452-7
Support type:Scholarships in Brazil - Post-Doctorate
Effective date (Start): November 01, 2016
Effective date (End): December 12, 2018
Field of knowledge:Biological Sciences - Parasitology - Entomology and Malacology of Parasites and Vectors
Principal Investigator:Sirlei Daffre
Grantee:Fernanda Dornelas Florentino Silva
Home Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
Associated research grant:13/26450-2 - Molecular characterization of the interactions among ticks, rickettsiae and vertebrate hosts, AP.TEM


Rickettsia rickettsii is the etiological agent of the Rock Mountain spotted fever known in Brazil as Brazilian Spotted Fever (BSF). It is a serious Rickettsial disease that affects humans and has high mortality rates may reach 40% with the highest incidence occurs in the Southeastern region of the country. Rickettsia rickettsii is an obligate intracellular gram-negative proteobacteria transmitted to humans by the bite of various species of ticks. In Central America and South America, including Brazil, the Amblyomma cajennense tick, known as the star tick is the main vector. In Brazil, more specifically in the metropolitan region of São Paulo, the yellow dog tick, Amblyomma aureolatum, is also recognized as a vector. The susceptibility to infections of ticks depends largely immune response that these animals are able of triggering when infected. We propose in this project to study the role of cell signaling pathways (Toll, IMD and JAK/STAT) involved in the control of the Rickettsia rickettsii infection in Amblyomma aureolatum ticks. The choice of this model is due to the experience that our group has acquired in recent years, both in maintaining the colony of infected ticks, as well as in molecular studies of Amblyomma-R. rickettsii interaction. Despite presenting important medical and veterinary, economic and public health, there is no efficient commercial vaccine for the prevention of FMB, the most severe rickettsial disease that affects humans. The results generated by this study will help in understanding how the immune system signaling pathways control the infection of R. rickettsii in the A. aureolatum tick and so devise strategies for the control of pathogen, as well as the tick itself. (AU)