Cytokine responses in primary chicken embryo intestinal cells infected with Campylobacter jejuni strains of human and chicken origin and the expression of bacterial virulence-associated genes.
BACKGROUND
Campylobacter jejuni is a major cause of inflammatory diarrhoea in humans and is considered a commensal of the gastroenteric tract of the avian host. However, little is known about the interaction between C. jejuni and the avian host including the cytokine responses and the expression of the bacterial genes. We have investigated the invasiveness of primary chicken embryo intestinal cells (CEICs) by C. jejuni strains of human and chicken origins and the production of pro-inflammatory cytokines as well as the expression of the bacterial virulence-associated genes during co-cultivation.


RESULTS
C. jejuni strains are capable of invading the CEICs and stimulate these cells in a pro-inflammatory manner and during this interaction the expression of the bacterial virulence-associated genes ciaB, dnaJ and racR is increased. Furthermore, incubation of bacteria with conditioned cell- and bacteria-free media from another co-cultivation experiment also increased the expression of the virulence-associated genes in the C. jejuni chicken isolate, indicating that the expression of bacterial genes is regulated by component(s) secreted upon co-cultivation of bacteria and CEICs.


CONCLUSIONS
We show that under in vitro culture condition C. jejuni strains of both human and chicken origins can invade avian host cells with a pro-inflammatory response and that the virulence-associated genes of C. jejuni may play a role in this process.
Li
Yi-Ping
YP
Department of Poultry, Fish and Fur Animals, National Veterinary Institute (VET), Technical University of Denmark (DTU), Hangøvej 2, DK-8200 Aarhus N, Denmark. yiping.li@hotmail.com
Ingmer
Hanne
H
Madsen
Mogens
M
Bang
Dang D
DD
D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002169:Campylobacter Infections / Q000382:microbiology* / Q000662:veterinary*; D016123:Campylobacter jejuni / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification / Q000472:pathogenicity; D002478:Cells, Cultured; D002642:Chick Embryo; D002645:Chickens; D016207:Cytokines / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000276:immunology / Q000382:microbiology; D009569:Nitric Oxide / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D011201:Poultry Diseases / Q000276:immunology* / Q000382:microbiology; D037521:Virulence Factors / Q000235:genetics* / Q000378:metabolism
D001426:Bacterial Proteins; D016207:Cytokines; D037521:Virulence Factors; D009569:Nitric Oxide; D052247:Nitric Oxide Synthase Type II