A multiepitope chimeric antigen from Rhipicephalus microplus-secreted salivary proteins elicits anti-tick protective antibodies in rabbit

Author(s)

Costa, Gabriel C. A. ; Silva, Fernando A. A. ; Manzato, Veronica M. ; Torquato, Ricardo J. S. ; Gonzalez, Yamile G. ; Parizi, Luiz F. ; Vaz Junior, Itabajara da Silva ; Tanaka, Aparecida S.

• Document type: Journal article
• Source: Veterinary Parasitology; v. 318, p. 11-pg., 2023-04-13.

Abstract

Rhipicephalus (Boophilus) microplus, the Cattle Fever Tick, causes significant economic losses in livestock in tropical and subtropical regions of the world. As the usual control strategy based on chemical acaricides presents different drawbacks, alternative control strategies have been considered for tick control. In recent decades, several tick proteins have been evaluated as targets for the development of anti-tick vaccines. Thus, in the present work, coding sequences from three different proteins present in tick saliva were employed together to construct a recombinant chimeric protein that was evaluated as an antigen in rabbit immunization. Then, the elicited antibodies were tested in a tick artificial feeding experiment to verify the protective effect against the parasites. In addition to Rhipicephalus microplus subtilisin inhibitor 7 (RmSI-7), a serine protease inhibitor member of the TIL (Trypsin Inhibitory Like) family, an interdomain region from the Kunitz inhibitor BmTI-A, and a new cysteine-rich AMP-like microplusin, called RmSEI (previously identified as an elastase inhibitor), were selected to compose the chimeric protein. Anti-chimeric IgG antibodies were able to affect R. microplus female egg production after artificial feeding. Moreover, antibodies elicited in infested tick-resistant and tick-susceptible cattle recognized the recombinant chimera. Additionally, the functional characterization of recombinant RmSEI was performed and revealed antimicrobial activity against gram-positive bacteria. Moreover, the antimicrobial protein was also recognized by antibodies elicited in sera from cattle previously exposed to R. microplus bites. Together, these data suggest that the chimeric protein composed of three salivary antigens is suitable for anti-tick vaccine development. (AU)

• FAPESP's process: 20/02433-5 - Library construction of cDNA fragments of R. microplus proteolytic enzymes (peptidases) and serpins on the surface of filamentous phages
• Grantee: Gabriel Cerqueira Alves Costa
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 12/03657-8 - Inhibitor and proteases of ectoparasites: relationship of structure-function and identification of the role of these molecules in the interaction of diseases vector e their etiological agents
• Grantee: Aparecida Sadae Tanaka
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 19/03779-5 - Use of phage display as a tool in the diagnosis and control of diseases transmitted by hematophagous vectors
• Grantee: Aparecida Sadae Tanaka
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 12/20597-9 - Interaction of proteases from Babesia bovis, the etiological agent of cattle babebiosis, with protease inhibitors from vector tick Rhiphicephallus (Boophilus) microplus, and its potential for vaccination.
• Grantee: Yamile Gonzalez Gonzalez
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 15/09268-1 - Characterization of two proteases from Babesia bovis parasite: Importance in the host infections.
• Grantee: Stephen Lu
• Support Opportunities: Scholarships in Brazil - Doctorate