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Engineering
a New Way to Study Hepatitis C
Advance
that could allow scientists to develop and test new treatments
for the disease
Cambridge, Mass. -- January 25, 2010 -- Researchers at MIT
and Rockefeller University have successfully grown hepatitis
C virus in otherwise healthy liver cells in the laboratory,
an advance that could allow scientists to develop and test
new treatments for the disease.
About 200 million people worldwide are infected with hepatitis
C, which can lead to liver failure or cancer, and existing
drugs are not always effective. To develop better treatments,
researchers need to test them in laboratory experiments
in liver cells, but it has been difficult to create a suitable
tissue model because healthy liver cells tend to lose their
liver functions when removed from the body.
Previously, researchers have been able to induce cancerous
liver cells to survive and reproduce outside the body, but
those cells are not sufficient for studying hepatitis C
because their responses to infection are different from
those of normal liver cells.
Now, Sangeeta Bhatia, professor in the Harvard-MIT Division
of Health Sciences and Technology, in collaboration with
Charles Rice of the Rockefeller University, has developed
a way to maintain liver cells for four to six weeks by precisely
arranging them on a specially patterned plate. The cells
can be infected with hepatitis C for two to three weeks,
giving researchers the chance to study the cells' responses
to different drugs.
The new model, described in next week's issue of the Proceedings
of the National Academy of Sciences, could allow researchers
to test the effectiveness of various combinations of drugs,
including interferon, a common current treatment, and experimental
antibodies that may block the virus from entering cells.
How they did it: The researchers used healthy liver cells
that had been cryogenically preserved and grew them on special
plates with micropatterns that direct the cells where to
grow. The liver cells were strategically interspersed with
other cells called fibroblasts that support the growth of
liver tissue.
"If you just put cells on a surface in an unorganized
way, they lose their function very quickly," says Bhatia.
"If you specify which cells sit next to each other,
you can extend the lifetime of the cells and help them maintain
their function."
Next steps: The current system may already be suitable to
screen drugs against the strain of hepatitis C used in this
work; however, this strain, which was derived from a Japanese
patient with fulminant hepatitis is the only strain ever
successfully grown in a laboratory environment. The researchers
hope to modify the system so they can grow additional strains,
such as those more common in North America, which would
allow for more thorough drug testing.
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