SEQUENCE ANALYSIS, TRANSCRIPTIONAL PROFILE AND VACCINE POTENTIAL OF THE RHIPICEPHALUS MICROPLUS PROTEIN BM05
Autor(es): María Fernanda Alzugaray , Gabriela Sabadin, Carolina Acevedo, Luis Fernando Parizi, Lucas Tirloni, Adriana Seixas , Patricia Berasain , Uruguaysito Benavides , Itabajara Da Silva Vas
SEQUENCE ANALYSIS, TRANSCRIPTIONAL PROFILE AND VACCINE POTENTIAL OF THE RHIPICEPHALUS MICROPLUS PROTEIN BM05
» Área de pesquisa: ACAROLOGIA
» Instituição: Centro de Biotecnología, Universidade Federal do Rio Grande Sul
» Agência de fomento e patrocinadores: CAPES, CNPq (Brazil) and UdelaR, INIA (Uruguay).
Rhipicephalus microplus is a cattle tick responsible for mayor losses in livestock due to transmission of disease agents and blood spoliation. Utilization of vaccines for tick control is a promising tool, however the identification of new potential antigen candidates is essential. Hq05 is an antigen that induces immune protection against tick Haemaphysalis qinghaiensis. The objective of the present study was to characterize the R. microplus Hq05-like (Bm05) and evaluate the protective capacity of recombinant Bm05 (rBm05) for use in a multi-antigenic vaccine together with R. microplus Bm86 antigen from a Uruguayan isolate (Bm86uy). By RT-PCR, the Bm05 transcription profile from midgut, ovary, salivary glands and carcass from partially engorged females (PEF) and fully engorged females (FEF) was analyzed. Escherichia coli BL21 (DE3) strain was transformed with the plasmid pET5a-Bm05 for further rBm05 expression and purification. rBm05 plus rBm86uy were used for bovine immunization. Bm05 open reading frame (ORF) codes for a protein of 171 amino acid residues (19.1 kDa). Comparison of Bm05 amino acid sequence with tick genes deposited in GenBank revealed the homology to sequences from Rhipicephalus annulatus (100% similarity), Haemaphysalis longicornis (86% similarity), Ixodes scapularis (72% similarity) and H. qinghaiensis (62% similarity). Bm05 mRNA is transcribed in ovary, salivary glands and carcass from PEF and FEF, and only in midgut from PEF. Experimental R. microplus infestation showed that cattle immunized with rBm05 and rBm86uy developed a humoral immune response that was partially protective. These results show that rBm05 and rBm86uy are potential candidates as a component of an anti-tick vaccine cocktail.
