Bacteria Wins First Round Against Inflammatory Bowel
By Ann Perry
December 30, 2009
A group of British scientists and
their Agricultural Research Service (ARS)
colleague used a benign bacterium from the human gut to develop a microbe that
someday might help treat inflammatory bowel disease (IBD) and other chronic
IBD erodes the delicate lining of the intestine, and its symptomsoften
severeinclude cramping, abdominal pain and other gastrointestinal
discomfort. IBD cannot be cured, and current treatments can have adverse side
effects. Medical practitioners and patients are anxious for the development of
more effective therapies, particularly protocols that deliver drugs directly to
So ARS microbiologist
Whitehead, who works at the
Center for Agricultural Utilization Research in Peoria, Ill., and his
partners began searching for a solution. Simon Carding, who works at the
Institute of Food Research and the
University of East Anglia in Norwich, Great
Britain, led the research project with Zaed Hamady, who works at the
University of Leeds in Great Britain and
St. James University
Hospital, also in Leeds.
The group focused on the bacterium Bacteroides ovatus (B.
ovatus), which is one of an assortment of intestinal microflora in humans.
B. ovatus thrives in the oxygen-free environment of the large intestine,
where it breaks down xylana fiber found in plantsand other sugars
for energy and growth.
The team created a strain of B. ovatus that used xylan to induce
secretion of human keratinocyte growth factor, a protein that helps repair and
restore the intestines delicate lining. This increased the ability of the
intestine to repair IBD-inflicted damage.
The researchers found that IBD-affected mice treated with oral doses of
xylan and the engineered strain of B. ovatus had intestinal tissues that
healed more rapidly. This group of mice also lost less weight and had lower
levels of rectal bleeding. In addition, dosing mice with B. ovatus
provided protection from induced IBD and limited the development of subsequent
An abstract of this research was published online in the journal Gut.
ARS is the principal intramural scientific research agency of the
U.S. Department of Agriculture.