Fatores de patogenicidade e potencial risco à saúde em Campylobacter spp. isolados de carcaças de frangos

Abstract

This study evaluated the incidence of Campylobacter spp. in chicken carcasses in three states in Brazil, antibiotic resistance, the presence of virulence genes and their transcription, the expression and the changes brought about after inoculation in Caco-2 cells and the phylogenetic relationship among species. Were isolated 94/420 Campylobacter spp., being 55 C. jejuni, 19 C. coli and 20 Campylobacter spp. There was resistance to amoxicillin (74.5%), norfloxacin (43.6%) and erythromycin (36.2%) and sensitivity to neomycin (97.9%) and gentamicin (95.7%), and C. coli was the most resistant. Regarding the virulence genes 45/94 (47.9%) had the flaA gene, 42/94 (44.7%) plda, 43/94 (45.7%) cadF, 42/94 (44.7%) ciaB and 37/94 (39.4%) cdtABC with C. jejuni more virulent. The analysis of transcripts included the 56 strains with virulence genes, 32/56 (57.1%) strains positive, with stronger evidence for C. jejuni. Of the 46 C. jejuni strains with virulence genes, 18 (39.1%) did not transcribed ciaB and dnaJ. Thus, 14/18 strains were inoculated into Caco-2 cells, and found that 2/14 (14.3%) expressed ciaB, and all, dnaJ. Five C. jejuni, the most virulents, promoted the loss of intercellular confluency and caused changes in Caco-2 cells. The similarity analysis showed a high diversity in C. jejuni and C. coli. In Campylobacter spp., the genetic proximity indicates that they may belong to the same species. This study highlighted the phenotypic and genotypic characters of Campylobacter spp. and potential role in pathogenesis of human disease, emphasizing the need for tight controls on production to ensure the health of consumers.