WOOSTER, Ohio - Ohio State University researchers are hoping that a protein in a food-borne pathogen may lead to vaccine development in its common host - chickens.
Qijing Zhang, a researcher with the university's Food Animal Health Research Program, has been awarded a three-year U.S. Department of Agriculture grant to study the "major outer membrane protein" of Campylobacter jejuni, a bacterium that harmlessly resides in birds, including poultry. However, the pathogen can produce campylobacteriosis in humans, a gastrointestinal illness similar to Salmonella and E. coli.
"Campylobacter is the number one food-borne pathogen in the U.S. in terms of number of incidents each year," said Zhang. In addition to its high prevalence in birds, this pathogen has become increasingly resistant to antibiotics used to treat human illnesses, posing another challenge for controlling Campylobacter diseases. Several studies have estimated that 80-100 percent of broiler chicken carcasses are contaminated with Campylobacter.
Last year, OSU researchers discovered the Campylobacter gene encoding the "major outer membrane protein," a protein that maintains the structural integrity of the pathogen and helps it adapt to the gut of its host. Zhang and his associates speculated that the protein could be used to develop vaccines because this protein is produced in large quantities in every Campylobacter strain.
"Also, every strain appears to have a unique protein sequence," said Zhang. "If this is found to be true, we can use the protein sequence as a marker to differentiate various strains of Campylobacter. We can also identify the specific regions of the protein that can induce protective immunity to Campylobacter infections." Researchers are currently testing 150 Campylobacter strains.
According to the Centers for Disease Control, an estimated 2.1 to 2.4 million cases of campylobacteriosis occur in each year, making it the most common food-borne bacterial pathogen in the United States. Symptoms include fever, abdominal cramps and diarrhea. People most commonly contract campylobacteriosis by mishandling raw chicken, eating undercooked chicken, or drinking contaminated water or milk.