The control of ticks through vaccination offers a sustainable alternative to the use of chemicals that cause contamination and the selection of resistant tick strains. However, only a limited number of anti-tick vaccines have reached commercial realization. In this sense, an antigen effective against different tick species is a desirable target for developing such vaccines. A peptide derived from the tick P0 protein (pP0) conjugated to a carrier protein has been demonstrated to be effective against the Rhipicephalus microplus, Rhipicephalus sanguineus, and Amblyomma mixtum tick species. The aim of this work was to assess the efficacy of this peptide when conjugated to the Bm86 protein against Dermacentor nitens and Ixodes ricinus ticks. An RNAi experiment using P0 dsRNA from I. ricinus showed a dramatic reduction in the feeding of injected female ticks on guinea pigs. In the follow-up vaccination experiments, rabbits were immunized with the pP0-Bm86 conjugate and challenged simultaneously with larvae, nymphs, and the adults of I. ricinus ticks. In the same way, horses were immunized with the pP0-Bm86 conjugate and challenged with D. nitens larva. The pP0-Bm86 conjugate showed efficacies of 63% and 55% against I. ricinus and D. nitens ticks, respectively. These results, combined with previous reports of efficacy for this conjugate, show the promising potential for its development as a broad-spectrum anti-tick vaccine.

• Publikační typ
• časopisecké články MeSH

The class Mollicutes comprises microorganisms that lack a cell wall, highly dependent on their host to survive. Within Mollicutes, the genus Spiroplasma comprises motile helical microorganisms associated with various insects and other arthropods. This study aimed to detect and characterize Mollicutes microorganisms in ticks of different species of veterinary importance, using molecular techniques. These ticks were collected from dogs, cats, cattle, and horses from Rio de Janeiro's metropolitan regions. They were morphologically classified and pooled according to their species for subsequent DNA extraction. These samples were tested by PCR using class Mollicutes-specific primers (16S rRNA) and positive amplicons were sequenced. The obtained DNA sequences were compared with other Mollicutes sequences deposited in GenBank. We found that four out of 745 (0.54%) of the tick pools were positive for members of the class Mollicutes, identified as Spiroplasma spp.; of the positive pools, one comprised Amblyomma sculptum adults and three comprised Dermacentor nitens nymphs. The present study describes Spiroplasma spp. in ticks in Brazil for the first time. Nevertheless, due to few reports on these microorganisms, further studies on epidemiology, virulence, and pathogenicity are needed.

• MeSH
• klíšťata * MeSH
• koně MeSH
• nymfa MeSH
• RNA ribozomální 16S genetika   MeSH
• Spiroplasma * genetika   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Brazílie MeSH