Submitted to: Avian Diseases
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 29, 1998
Publication Date: N/A
Interpretive Summary: One common cause of human food poisoning is the microorganism Campylobacter jejuni. This organism resides in the intestines of chickens, and sometimes finds its way from there into our food. Our research looked at how Campylobacter survives in the intestines of chickens. We found that Campylobacter have a gene, called cadF, which is responsible for the ability of Campylobacter to attach to the surfaces of the intestines. The discovery of this gene is expected to provide new ways to protect chickens from Campylobacter, possibly by vaccination. Our work opens a new approach to preventing Campylobacter from taking up residence within the intestines of chickens. If the organism can be kept out of chickens, it can be kept out of food for human consumption, thus reducing the incidence of human food poisoning.
Technical Abstract: Campylobacter jejuni is a very common cause of human gastrointestinal illness and poultry products are thought to be a frequent source of this foodborne pathogen. The ability of C. jejuni to establish in the gastrointestinal tract of chickens is believed to involve binding of the bacterium to the gastrointestinal surface. A 37 kDa outer membrane protein named CadF has been described which binds Campylobacter to fibronectin. Experiments were conducted to determine if this fibronectin-binding protein has a role in the ability of C. jejuni to colonize the cecum of newly hatched chicks. Day-of-hatch chicks were orally challenged with either C. jejuni F38011, a human clinical isolate, or a derivative isogenic strain in which the cadF gene was disrupted rendering the bacterium incapable of producing CadF. CadF deficient C. jejuni were found to be incapable of successfully colonizing the cecum. CadF deficient C. jejuni were not recovered from any of 60 chicks challenged with the CadF deficient strain. In contrast, the parental C. jejuni F38011 readily colonized and C. jejuni levels sometimes exceeded 10**8 bacteria per gram of cecal contents. These results are very suggestive of the role played by CadF in cecal colonization by C. jejuni and indicate that CadF may be useful as a specific acellular vaccine constituent.