Effects of anti-tick cocktail vaccine against Rhipicephalus appendiculatus

Jpn J Vet Res. 2008 Aug;56(2):85-98.

Abstract

Rhipicephalus appendiculatus serpin-3 (RAS-3), R. appendiculatus serpin-4 (RAS-4) and a 36-kDa immuno-dominant protein of R. appendiculatus (RIM36) were reported as candidate antigens for the anti-tick vaccine to control ixodid ticks. In the present study, we generated recombinant proteins of RAS-3 (rRAS-3), RAS-4 (rRAS-4) and RIM36 (rRIM36), and assessed their potency as an anti-tick cocktail vaccine in cattle model. RT-PCR analysis showed that RAS-3, RAS-4 and RIM36 transcripts were detected in both adult male and female ticks during feeding. Immunization of cattle with the combination of rRAS-3, rRAS-4 and rRIM36 had raised antibodies against all recombinants and anti-sera had reacted with the molecules from the tick salivary gland extract. Tick infestation challenge demonstrated protective immunity against female ticks, resulting in mortality rates of 39.5 and 12.8% for the vaccinated and control groups, respectively. Moreover, the mortality rate of Theileria parva-infected female ticks was 48.5 and 10.8% in the vaccinated and control group, respectively. In order to evaluate the levels of pathogen transmission capacity by T. parva-infected ticks fed on immunized cattle, the occurrence of T. parva in the bovine parotid lymph node and peripheral blood was also determined and quantified by real-time PCR. Although the infection with T. parva could not be protected by the vaccine, the occurrence of pathogen in peripheral blood was delayed 1 to 2 days after the infestation challenge in vaccinated group. These results suggest that this cocktail vaccine plays a role in the prevention of tick infestation.

Publication types

  • Controlled Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cattle
  • DNA, Complementary / isolation & purification
  • Feeding Behavior
  • Female
  • Insect Control
  • Insect Proteins / immunology*
  • Male
  • Protein Denaturation
  • Recombinant Proteins
  • Rhipicephalus / immunology*
  • Serpins / immunology*
  • Theileria parva
  • Tick Infestations / immunology*
  • Vaccines, Synthetic / immunology*

Substances

  • DNA, Complementary
  • Insect Proteins
  • Recombinant Proteins
  • Serpins
  • Vaccines, Synthetic