Resposta celular à infecção por Campylobacter. jejuni em embriões e explants de íleo de aves e participação do citoesqueleto e lisossomos no processo de invasão em células CACO-2

Abstract

The host-pathogen interactions of C. jejuni is a little explored subject in birds and humans. Thus, this study aimed to evaluate the passage and the effects of virulent strain of C. jejuni IAL 2383 in SPF embryos of birds, the expression of cytokines and morphological changes in SPF birds explants ileum infected with C. jejuni and verify the cytoskeleton and lysosomes participation in the processes of invasion and internalization of C. jejuni in Caco-2 cells and the cellular response by quantifying the expression of inflammatory cytokines. The experiment with eggs and embryos indicated that C. jejuni passes through the pores of the eggs, colonizes the vitellus and lead to high early embryonic mortality and increase the embryos enterocytes dimensions. In avian explants, the bacteria invades, increases the size of enterocytes and induces the expression of TGF-β3 and early IL-1β with 4hours of infection. The invasion process in Caco-2 cells is dependent on actin microfilaments and tubulin and to internalize the bacteria fused with lysosomes. The cellular response is the distention and cell expression of IL-8, a potent pro-inflammatory cytokine. These results indicate that C. jejuni is not just a commensal in birds. In addition, this microorganism invasion in Caco-2 cells is dependent on actin and tubulin and internalization leads to fusion with lysosomes, which causes bacterial degradation by inducing the production of inflammatory cytokines and cell strain.