Vaccination with recombinant Boophilus annulatus Bm86 ortholog protein, Ba86, protects cattle against B. annulatus and B. microplus infestations.

Mario Canales,José De La Fuente,Consuelo Almazán,Frans Jongejan,Victoria Naranjo

doi:10.1186/1472-6750-9-29

Abstract

BackgroundThe cattle ticks, Boophilus spp., affect cattle production in tropical and subtropical regions of the world. Tick vaccines constitute a cost-effective and environmentally friendly alternative to tick control. The recombinant B. microplus Bm86 protective antigen has been shown to protect cattle against tick infestations. Recently, the gene coding for B. annulatus Bm86 ortholog, Ba86, was cloned and the recombinant protein was secreted and purified from the yeast Pichia pastoris.ResultsRecombinant Ba86 (Israel strain) was used to immunize cattle to test its efficacy for the control of B. annulatus (Mercedes, Texas, USA strain) and B. microplus (Susceptible, Mexico strain) infestations. Bm86 (Gavac and Mozambique strain) and adjuvant/saline were used as positive and negative controls, respectively. Vaccination with Ba86 reduced tick infestations (71% and 40%), weight (8% and 15%), oviposition (22% and 5%) and egg fertility (25% and 50%) for B. annulatus and B. microplus, respectively. The efficacy of both Ba86 and Bm86 was higher for B. annulatus than for B. microplus. The efficacy of Ba86 was higher for B. annulatus (83.0%) than for B. microplus (71.5%). The efficacy of Bm86 (Gavac; 85.2%) but not Bm86 (Mozambique strain; 70.4%) was higher than that of Ba86 (71.5%) on B. microplus. However, the efficacy of Bm86 (both Gavac and Mozambique strain; 99.6%) was higher than that of Ba86 (83.0%) on B. annulatus.ConclusionThese experiments showed the efficacy of recombinant Ba86 for the control of B. annulatus and B. microplus infestations in cattle and suggested that physiological differences between B. microplus and B. annulatus and those encoded in the sequence of Bm86 orthologs may be responsible for the differences in susceptibility of these tick species to Bm86 vaccines.

Highlights

The cattle ticks, Boophilus spp., affect cattle production in tropical and subtropical regions of the world
The vaccination with recombinant Ba86 and Bm86 protected cattle against B. annulatus and B. microplus infestations This is the first report on the protective capacity of recombinant Ba86 for the control of cattle tick infestations
To evaluate the protective capacity of Ba86 against B. microplus and B. annulatus infestations, cattle were vaccinated with the recombinant protein and compared to cattle vaccinated with two Bm86 preparations and adjuvant/saline control

Summary

Introduction

The cattle ticks, Boophilus spp., affect cattle production in tropical and subtropical regions of the world. Use of acaricides has had limited efficacy in reducing tick infestations and is often accompanied by serious drawbacks, including the selection of acaricide-resistant ticks, environmental contamination and contamination of milk and meat products with drug residues [5]. All of these issues reinforce the need for alternative approaches to control tick infestations such as the use of hosts with natural resistance to ticks, pheromone-impregnated decoys for attracting and killing ticks, biological control agents and vaccines [6,7,8]

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Results

Conclusion