ABSTRACT
Phage display techniques have been widely employed to map epitope structures which have served as the basis for developing molecular vaccines. We have applied this technique to map specific epitopes of Rhipicephalus (Boophilus) microplus. In the present study, we have identified the potential immunogens using a process in which the selected phage clones were analyzed through bioinformatics, prior to final field tests. The present study demonstrates the feasibility of identifying important R. (B.) microplus phagotopes for vaccine development through screening of phage-displayed random peptide libraries and bioinformatics tools.
Técnicas de phage display têm sido amplamente empregadas para o mapeamento de epítopos os quais tem servido como base para o desenvolvimento de vacinas moleculares. Esta técnica foi aplicada no mapeamento de epítopos do Rhipicephalus (Boophilus) microplus. Neste estudo, potenciais imunógenos foram identificados pela adoção de um processo em que os clones de fagos foram analisados por bioinformática, previamente à realização dos testes. Os resultados demonstraram a possibilidade da identificação de importantes mimetopos do R. (B.) microplus para o desenvolvimento de vacinas através da seleção de bibliotecas de phage display associada à análise de bioinformática.
Subject(s)
Animals , Peptide Library , Ticks/classificationABSTRACT
The cattle tick Boophilus microplus causes great damage in livestock and is considered one of the most important tropical ectoparasites. The traditional method of control is based on the intensive use of pesticides, however the indiscriminate use of these compounds over the years has led to the selection of resistant ticks. Hydrolases, particularly esterases (EST), have been reported to be associated with acaricide resistance in B. microplus. We compared the esterase profile of susceptible and cypermethrin-resistant strains of adult B. microplus and a pyrethroid susceptible reference strain (the Mozzo strain) using polyacrylamide gel electrophoresis and specific staining. The electrophoretic profiles of protein extracts revealed the presence of four regions with esterase activity in the cypermethrin-resistant strain and three of these regions in the susceptible strains. The bands were numbered EST-1 to EST-4 in sequence (starting from the anode) according to their decrease in negative charge. The EST-1A and EST-1B enzymes were detected only in the resistant strain. The inhibition studies with eserine sulfate, copper sulfate, p- p-chloromercuribenzoate (pCMB), malathion and phenylmethylsulfonyl fluoride (PMSF) indicated that the EST-1A and EST-1B enzymes belong to the acetylcholinesterase class and are probably associated with resistance to acaricides in this Brazilian resistant strain of B. microplus.