Interação de Aeromonascaviae e hydrophila com células intestinais e epiteliais humanas in vitro e epitélio intestinal de coelhos ex vivo

• Autor(a) principal: Santos, Paula Azevedo dos
• Data de Publicação: 2016
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/14367
• topic: Aeromonas spp; Adhesion; Invasion; Intracellular survival; Cytotoxic effects; In vitro organ culture (IVOC); Aeromonas spp; Aderência; Invasão; Persistência intracelular; Citotoxicidade; Cultura de órgão in vitro (IVOC); Aeromonas; Células Interação; Citotoxicidade; Técnicas in vitro; Adesão celular; CNPQ::CIENCIAS BIOLOGICAS::MICROBIOLOGIA::MICROBIOLOGIA APLICADA::MICROBIOLOGIA MEDICA

Aeromonas is an important pathogen for humans and animals and is responsible for the etiology of intestinal and extraintestinal diseases. The presence of Aeromonas spp. in food and water demonstrates that it s an important vehicle of infection in humans. The pathology caused by these bacteria involves several virulence factors, such as the ability to adhere, invade and produce toxins. The properties conferred by these factors have been extensively studied in experiments of interaction between bacterial strains and cell culture. However, there is no animal model established to study Aeromonas spp. pathogenesis. The present study assessed the interaction of eight Aeromonas spp. strains, previously isolated from human faeces, food and water with HEp-2, Caco-2 and T-84 cell lines as to the cytotoxic effects, the pattern of adhesion, invasive capacity and intracellular survival. We also evaluated the interaction of five A. caviae strains isolated from human diarrheic faeces with rabbit ileal and colonic mucosa ex vivo, using in vitro organ culture model (IVOC). The results showed that Aeromonas strains were adherent to three cells lines in 6 h of incubation, displaying the aggregative adherence pattern. Among eight strains studied, 50 % produced cytotoxic effects on HEp-2 cells, while none of the strains produced cytotoxic effects on Caco-2 and T-84 cells at 48 h. This study demonstrated that strains of Aeromonas isolated from different sources were able to invade intestinal (T-84, Caco-2) and epithelial (HEp-2) cell lines cultivated in vitro surviving within intracellular environments up to 72 h. All strains adhered to rabbit ileal and colonic mucosa, with higher degree of adherence on the colonic mucosa. The typical aggregative adherence pattern was observed among all strainsstudied. Through electron microscopy and light microscopy we observed extensive colonization of ileal and colonic mucosa, large mucus production, biofilm formation and morphological alterations such as intense vacuolization, structural disorganization, cell extrusion and destruction of the villi. Our study demonstrated that the in vitro organ culture (IVOC) of rabbit intestinal mucosa may be used to investigate the mechanisms of pathogenesis of Aeromonas spp. Our results also contributed to reinforce the pathogenic potential of Aeromonas strains, confirming its importance inpublic health.