Bad Blood Print
Written by Justin Reedy   
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Scientists have not yet created a vaccine for hepatitis C, though recent findings by UW researchers may help pave the way for one. Fausto and his UW colleagues recently created a method for culturing hepatitis C virus in a research-friendly environment—human liver cells, known as hepatocytes. Previous studies have relied on special strains of the virus that can grow in cell culture systems, but could not replicate for long periods of time or produce more virus.

Putting the virus in the old culture system was like putting the seed of a plant in a tiny puddle or piece of soil—it might sprout, but could only grow so far. The new method is more like a pot filled with soil—the seed can keep growing into a fledgling plant. In this case, the virus can keep replicating for months at a time in human liver cells, a venue that is very close to the setting for the real infection.

“We maintained it for three months, which is very helpful when studying chronic infections,” says Jean Campbell, an instructor in pathology and a scientist in Fausto’s lab. “This setting is so much closer to your liver or my liver, that you can now start asking questions about the progression of the virus in a patient. Before you couldn’t even really ask those questions.”

The virus culture system should make significant improvements in the study of hepatitis C virus, Fausto says. He and Campbell are optimistic that this step could one day help lead to the creation of a vaccine, or perhaps the creation of other, better treatments. Similar advancements in HIV research have led to a few promising candidates for a vaccine against that virus.

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Famous people living with hepatitis C include, left to right, actress Pamela Anderson, country singer Naomi Judd and Aerosmith's lead singer Steven Tyler. All photos © Associated Press. Photographers (left to right): Shizuo Kambayashi, James A. Finley, Kevork Djansezian.
“HIV vaccines got such a foothold when Robert Gallo developed a culture system for that virus,” Campbell explains. “This set up a huge response in the pharmaceutical industry.”

Culturing the virus in human liver cells may also help researchers figure out why the combination therapy of interferon and ribavirin only works with certain strains of hepatitis C, and why people with other strains don’t respond as well or at all to that treatment.

Another option would be to create a therapeutic vaccine—a type of vaccine that would be given to people who are already infected—in the hope of eliminating the virus from their body or diminishing its effects. One possible approach for a therapeutic vaccine would be to begin attacking a portion of the virus that doesn’t adapt or mutate well.

“By studying the genetic sequence of the virus, we can learn where it doesn’t like to mutate,” says Gretch. “If we can get the immune system to attack that area, then it may get rid of the virus.”

In the meantime, much research on hepatitis C virus is aimed at increasing the survival rate of the chronic infection and its companion condition, liver disease. Gretch is taking part in a study called HALT-C (Hepatitis C Antiviral Long-term Treatment against Cirrhosis), which is studying whether low-dose interferon can help stave off liver cirrhosis in patients with advanced disease who haven’t responded to other treatments.

Now, such patients who progress to full cirrhosis are left with essentially one option: the chance of a liver transplant. Researchers hope that low-dose interferon can help stave off cirrhosis, even in patients who previously received full interferon treatment but weren’t able to clear the infection.

Projects like this at the UW and other institutions could make a significant impact on a global disease. But hepatitis C carries a bad reputation. Though some who contracted the virus in the United States during the 1970s, ’80s and ’90s were unfortunate victims of infected organs or blood transfusions, others got it through sharing needles during intravenous drug use. The sharing of dirty needles has become the biggest source of hepatitis C transmission around the world, as well.

Supporting research on drug addiction-related diseases can be a political hot-button. Consequently, some researchers have had difficulty receiving funding for their hepatitis C work. Fausto and his colleagues, for example, have no further resources to continue their work on the virus culture system. Though the field of hepatitis C research has done well in recent years, trying to fight or eliminate this deadly virus can be a hard sell in the politicized world of biomedical research funding. • Justin Reedy is a science writer and editor for Health Sciences/UW Medicine News and Community Relations.