RESUMO
This study aimed to evaluate the participation of actin and tubulin in the process of internalisation, the interaction of bacterial phagosomes with lysosomes, the morphometric changes and the expression of inflammatory cytokines in Caco-2 cells infected with Campylobacter jejuni. Both actin and tubulin participated in the process of internalisation. Inside the cells, lysosomes fuse with phagosomes, which may lead to bacterial death because after 2 h, the bacteria were not detected by Transmission electron microscopy (TEM). There is increased expression of TGF-ß3 during the early stages, and IL-8 was expressed after 60 min p.i. This work showed that C. jejuni invades and causes major morphometric changes in epithelial cells. In response, the cells increase their expression of cytokines that can lead to inflammation. The mechanisms of invasion are dependent on actin and tubulin, and once internalised, lysosomes fuse with phagosomes.
RESUMO
1. The objective of this study was to evaluate the ability of Campylobacter jejuni to penetrate and colonise eggs from specific-pathogen-free (SPF) and heavy breeder hens, and to determine its effects on the viability of SPF embryos. 2. We detected C. jejuni in 10% of breeder hens and 20% of SPF eggs, which demonstrates the ability of the bacteria to go through the pores of eggs and contaminate the vitellus after 3 h of contact. These results indicate that there is a risk of contamination under commercial production conditions, where, after oviposition, there is contact between the egg and organic material such as faeces and blood. 3. We observed that in 80% of SPF eggs analysed, C. jejuni survived the 21-d incubation period. This positive result suggests that this microorganism was also responsible for early embryonic mortality. 4. The ability of C. jejuni to penetrate the eggs in this study suggests that serious problems may occur under natural field conditions, which may cause significant problems for producers.
