Immunogenic potential of the aquaporin and of the P0 peptide against the tick Rhipicephalus sanguineus in dogs

• Grant number: 13/23934-9
• Support Opportunities: Regular Research Grants
• Start date: December 01, 2014
• End date: November 30, 2016
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Pathology
• Principal Investigator: Rosangela Zacarias Machado
• Grantee: Rosangela Zacarias Machado
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil

Abstract

The tick Rhipicephalus sanguineus has great medical and veterinary importance, since it acts as a vector of pathogens (viruses, bacteria, protozoa and nematodes), causing diseases in its hosts, including humans. The control of this tick species has been mainly based on the use of chemical acaricides, however their indiscriminate use has contributed to the selection of resistant ticks, in addition to high costs and environmental contamination. Vaccines have been considered a promising alternative for the control of ticks, although, to date, no commercial anti-tick vaccine is available for use in dogs. With the advancement of molecular biology techniques, new molecules have emerged as candidates for vaccines for cattle ticks and potentially for dogs. Among these molecules highlights the ribosomal protein P0 of R. sanguineus and R. microplus and a sequence encoding an aquaporin of R. microplus. Recent studies have also shown the possibility of vaccines developed for a determined tick species confer cross-protection for other species genetically close. Thus, this study aims, in collaboration with the Centro de Ingeniería Genética y Biotecnologia de Havana - CIGB, Cuba, and the United States Department of Agriculture - USDA, to evaluate the efficacy of peptide vaccines P0 and aquaporin against R. sanguineus in dogs in a challenge infestation through determination of the ticks biotic potential, histopathology of ticks fed on vaccinated hosts including the tick ultrastructure, histopathology of the tick attachment site, antibody anti-aquaporin and anti-P0, and immunohistochemistry of unfed ticks and fed ticks on vaccinated hosts. (AU)