http://dailynews.yahoo.com/h/nm/20010522/hl/ecoli_1.html

 

 

Cattle-Feed Vaccine Could Lower E. Coli Risk

By E. J. Mundell

ORLANDO (Reuters Health) - Scientists say they are busy developing an edible vaccine that could stop the E. coli bacteria (news - web sites) where it starts—in cattle and other livestock.

The best way to deliver such a vaccine would be to add it to the animals’ feed, explained researcher Nicole Roup, a graduate student at the Uniformed Services University of the Health Sciences in Bethesda, Maryland.

“We’re looking specifically at corn,” Roup said. She presented her findings here Tuesday at the annual meeting of the American Society for Microbiology.

The E. coli 0157:H7 strain is the most common cause of infectious bloody diarrhea in the United States, linked to nearly 73,000 cases every year. These types of illness can be especially harmful—even deadly—in the elderly, the very young or those with compromised immune systems, such as people with HIV (news - web sites).  Individuals usually contract the illness via contaminated food or water.

Because cattle are a main reservoir for E. coli, it made sense to try to combat the problem there, Roup told Reuters Health. Previous research had demonstrated that plants make cheap, safe vehicles for the transmission of vaccines, so Roup set about finding a suitable E.  coli vaccine for introduction into plant cells.

She settled on a protein called intimin, found on the outer coat of the E. coli organism. Intimin “helps the bacteria adhere to the intestinal surface,” Roup explained. It also wreaks havoc on the intestinal wall, causing the bleeding that characterizes E. coli-linked diarrhea.

Priming the cattle’s immune system to recognize intimin could serve as a potent vaccine to reducing E. coli infection rates, Roup theorized. Her studies in tobacco plant cells showed that plants can be genetically engineered to carry genes expressing intimin. And in experiments in mice, animals fed genetically-altered plant cells displayed an “intimin-specific immune antibody response,” Roup said.

The next step is testing the vaccine in cattle feed. Of course, the genetic manipulation of cattle feed could raise worries in a public already wary of genetically-modified crops. But the Maryland researcher believes the potential benefits of a corn-based cattle vaccine are “so promising, that with education as to its capacity to prevent human disease, people will be more receptive.”

 

 

 

ALL INFORMATION, DATA, AND MATERIAL CONTAINED, PRESENTED, OR PROVIDED HERE IS FOR GENERAL INFORMATION PURPOSES ONLY AND IS NOT TO BE CONSTRUED AS REFLECTING THE KNOWLEDGE OR OPINIONS OF THE PUBLISHER, AND IS NOT TO BE CONSTRUED OR INTENDED AS PROVIDING MEDICAL OR LEGAL ADVICE.  THE DECISION WHETHER OR NOT TO VACCINATE IS AN IMPORTANT AND COMPLEX ISSUE AND SHOULD BE MADE BY YOU, AND YOU ALONE, IN CONSULTATION WITH YOUR HEALTH CARE PROVIDER.