EX VIVO MODEL OF RABBIT INTESTINAL EPITHELIUM APPLIED TO THE STUDY OF COLONIZATION BY ENTEROAGGREGATIVE ESCHERICHIA COLI.
BACKGROUND
The diarrheal syndrome is considered a serious public health problem all over the world and is considered a major cause of morbidity and mortality in developing countries. The high incidence of enteroaggregative Escherichia coli in diarrheal syndromes classified as an emerging pathogen of gastrointestinal infections. After decades of study, your pathogenesis remains uncertain and has been investigated mainly using in vitro models of adhesion in cellular lines.


OBJECTIVE
The present study investigated the interaction of enteroaggregative Escherichia coli strains isolated from childhood diarrhea with rabbit ileal and colonic mucosa ex vivo, using the in vitro organ culture model.


METHODS
The in vitro adhesion assays using cultured tissue were performed with the strains co-incubated with intestinal fragments of ileum and colon over a period of 6 hours. Each strain was tested with three intestinal fragments for each region. The fragments were analysed by scanning electron microscopy.


RESULTS
Through scanning electron microscopy we observed that all strains adhered to rabbit ileal and colonic mucosa, with the typical aggregative adherence pattern of "stacked bricks" on the epithelium. However, the highest degree of adherence was observed on colonic mucosa. Threadlike structures were found in greater numbers in the ileum compared to the colon.


CONCLUSIONS
These data showed that enteroaggregative Escherichia coli may have a high tropism for the human colon, which was ratified by the higher degree of adherence on the rabbit colonic mucosa. Finally, data indicated that in vitro organ culture of intestinal mucosa from rabbit may be used to elucidate the enteroaggregative Escherichia coli pathogenesis.
Departamento de Microbiologia, Imunologia e Parasitologia, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro.
Ricardo Luís Lopes
RLL
Braga
Departamento de Microbiologia, Imunologia e Parasitologia, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro.
Ana Claudia Machado
ACM
Pereira
Departamento de Microbiologia, Imunologia e Parasitologia, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro.
Paula Azevedo Dos
PAD
Santos
Departamento de Microbiologia, Imunologia e Parasitologia, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro.
Angela Corrêa
AC
Freitas-Almeida
Departamento de Microbiologia, Imunologia e Parasitologia, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro.
Ana Cláudia de Paula
ACP
Rosa
D000818:Animals; D001422:Bacterial Adhesion / Q000502:physiology*; D003106:Colon / Q000382:microbiology* / Q000648:ultrastructure; D004926:Escherichia coli / Q000502:physiology*; D004927:Escherichia coli Infections / Q000382:microbiology*; D006801:Humans; D007082:Ileum / Q000382:microbiology* / Q000648:ultrastructure; D007413:Intestinal Mucosa / Q000382:microbiology* / Q000648:ultrastructure; D008297:Male; D008855:Microscopy, Electron, Scanning; D010802:Phylogeny; D011817:Rabbits; D037521:Virulence Factors
D037521:Virulence Factors