TORONTO, Jan. 16 /CNW/ - The January 17, 2008 issue of the prestigious
journal, Nature, includes an article by researchers at The Hospital for Sick
Children (SickKids), University of Toronto and Harvard Medical School that
documents new knowledge about one chronic bacterial infection and suggests a
pattern for others.
SickKids scientist Dr. John Brumell and his colleagues studied Listeria
monocytogenes, a type of bacteria that causes food poisoning and has serious,
even lethal, consequences for pregnant women, young infants, the elderly and
people whose immune system is severely weakened. The infection, known as
listeriosis, can be acute as well as chronic, and the researchers have found
new evidence of how the bacteria sustain a chronic infection.
The discovery could lead to greater understanding of other chronic
infections such as tuberculosis and some forms of urinary tract infections and
Brumell's team normally works on Salmonella typhimurium, a different
bacterial species. Two years ago they wanted to do a comparison with another
bacterium that causes food poisoning. They chose Listeria monocytogenes, which
is found in unpasteurized cheese, and this led to a series of questions at the
intra-cellular level and conclusions about the toxin, listeriolysin O, that is
produced by the bacteria.
Their discovery responds to the long-standing question of how bacteria
can cause either acute or chronic infections. "We found that the same toxin,
which the bacteria are using to grow rapidly inside one part of the cell and
cause a serious and life threatening infection, apparently also allows the
bacteria to grow slowly inside another part of the cell and cause a chronic
infection," says Brumell.
While scientists have known for years that the listeriolysin O toxin
causes acute infection, Brumell's study of its role in chronic infections
illustrates how central this toxin is for causing disease. He and his team
will analyze their findings further and hope eventually to test their thesis
Infectious diseases are an important area of research at SickKids. Dr.
Upton Allen, Head of the Division of Infectious Diseases, says Brumell's work
will increase understanding of chronic infectious diseases. "I think this area
of research gives us a better understanding of the how's and the why's as they
relate to the genesis of some types of infection and will help us in our work
to control and prevent these kinds of infections."
The research was supported by grants from the Burroughs Wellcome Fund,
the Boehringer Ingelheim (Canada) Young Investigator Award in Biological
Sciences, the Canada Foundation for Innovation, the Ontario Innovation Trust,
the Ontario Ministry of Economic Development and Trade, the Natural Sciences
and Engineering Research Council of Canada, the Canadian Association of
Gastroenterology, and the Canadian Institutes of Health Research.
SickKids, affiliated with the University of Toronto, is Canada's most
research-intensive children's hospital and the largest centre dedicated to
improving children's health in the country. As an innovator in child health,
SickKids improves the health of children by integrating care, research and
teaching. The mission of SickKids is to provide the best in complex and
specialized care by creating scientific and clinical advancements, sharing our
knowledge and expertise and championing the development of an accessible,
comprehensive and sustainable child health system. For more information,
please visit www.sickkids.ca. SickKids is committed to healthier children for
a better world.
For further information:
For further information: Janice Nicholson, The Hospital for Sick
Children, (416) 813-6684, firstname.lastname@example.org