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New way to study
hepatitis C
February 1, 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.
Liver cells in a
micropatterned co-culture form tube-like structures (shown here in
green) that resemble bile capillaries found in a human liver.
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.
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.”
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.
Funding: Greenberg Medical Research Institute, Ellison Medical
Foundation, Starr Foundation, Ronald A. Shellow Memorial Fund, Richard
Salomon Family Foundation, Howard Hughes Medical Institute, and the
National Institutes of Health through the NIH Roadmap for Medical
Research, Grant 1 R01 DK085713-01. |