Cultura celular aplicada à detecção e isolamento de vírus e riquétsia presentes em carrapatos

Abstract

This study aims at the standardization of techniques for the implementation of cell culture in the isolation of viruses and Rickettsia from ticks. The experiment was made using cells from the Vero lineage, which were inoculated with tick’s macerates, filtered macerates and saliva, from species: Amblyomma ovale, Amblyomma sculptum e Rhipicephalus sanguineus. Subsequently, the cell plaques were incubated in temperatures 37ºC and 28ºC for the isolation of viruses and Rickettsia, respectively, being observed for a period of up to 10 days for the identification of possible cytopathic effects (CPE) in the plaques incubated at 37ºC and the execution of Gimenez staining method for the plaques incubated at 28ºC. Regarding the samples of inoculated macerate and saliva, alterations in cellular morphology and the presence of Rickettsia were not observed, with the exception of the cells that were inoculated with the Amblyomma ovale macerate, which were possibly infected with Rickettsia bellii, as the utilized tick presented this pathogen in the hemolymph test. Therefore, the ticks utilized for this study, probably, did not contain viruses or Rickettsia or, if they did, the cells had a refractory effect on them, or the viral replication did not cause any CPE. In conclusion, the implementation of cell culture for the inoculation of tick’s macerates and saliva was a success. The filtering of the macerate proved important, as it reduced the formation of cell aggregates and cellular mortality, while the saliva did not produce these alterations, this implementation will be important for the isolation of viruses and Rickettsia from ticks.