HEPATITIS BREAKTHROUGH AT UW

University of Washington scientists have devised a unique way to grow
the hepatitis C virus in the laboratory -- an important step in the
quest for a vaccine and improved treatment for what has become one of
the most widespread infectious diseases in the world.

The researchers for the first time were able to keep the virus
reproducing for at least two months, enabling it to infect liver
cells, where it does its devastating work.

"We'll be able to better see what damage is done to cells, and it
will provide a way to test antiviral agents ... and help develop a
vaccine," said Dr. Nelson Fausto, chairman of the UW department of
pathology, who directed the research.

Hepatitis C infects about 170 million people worldwide, including
more than 4 million in the U.S. The virus is carried in the blood and
is usually spread by contaminated needles during drug abuse. It is
also spread, rarely, by sex, by an infected mother to her child, or
by other contact with infected blood.

The disease becomes chronic in the majority of patients. After 20 to
30 years, about one-fifth of them have liver scarring that can lead
to cancer. Hepatitis C liver disease is the leading reason for
patients needing a liver transplant.

Fausto and his UW colleagues made headlines last June as the first
scientists to isolate human liver stem cells, which are the ancestors
of all liver cells. The cells were taken from aborted fetuses donated
to research, then grown in the lab and infused in mice, where they
replaced dead liver cells.

The team now has used the liver stem cells in developing the new lab
culture for hepatitis C, which is to be reported in the February
edition of The American Journal of Pathology.

It was a tedious process, taking about four years to perfect, Fausto
said. But the researchers proved in several ways that the culture is
a nourishing home for the virus.

Scientists injected the cells into a culture with genetic material
from the virus. The viruses then reproduced into the culture, the
culture itself was mixed with more cells, and those cells, too,
became infected.

The team also mixed the blood of patients with different strains of
hepatitis C into the culture of liver stem cells. Again, the virus
thrived and reproduced.

"I think we finally have it," said Fausto. "We can grow this virus in
normal [liver cells]."

Other scientists have grown the virus using cancerous liver cells or
using a virus from a patient with a rare case of rapidly escalating
hepatitis. But neither are typical of real-life infections, Fausto said.

Fausto said the next step in the research is to see whether
laboratory animals can be infected with the laboratory-grown viruses.
That would further establish the viability of the culture method as a
way to study the virus.

Universities and pharmaceutical companies alike have "tremendous
interest" in developing a vaccine and more treatments, because
hepatitis C affects so many people, Fausto said.

It is difficult research, he said, but he predicted that a vaccine
could be developed in about five years, and testing of it completed
in a few more years.