Improved culture system for hepatitis C virus infection

July 15, 2008

A University of California, San Diego School of Medicine researcher has developed the first tissue culture of normal, human liver cells that can model infection with the Hepatitis C virus (HCV) and provide a realistic environment to evaluate possible treatments. The novel cell line, described in the July 16 issue of PLoS ONE, will allow pharmaceutical companies to effectively test new drug candidates or possible vaccines for the HCV infection, which afflicts about 170 million people worldwide. Currently, there is no animal model that is effective for testing such therapies.

Assistant Professor of Medicine Martina Buck, Ph.D., researcher at UC San Diego's Department of Medicine and Moores UCSD Cancer Center developed the novel culture system, which mimics the biology of HCV infection in humans.

"This is the first efficient and consistent model system for HCV to be developed," said Buck, adding that it will now enable researchers not only to conduct mechanistic experiments in culture, such as blocking the virus pathways, but also to more effectively screen possible therapies for HCV. "There is a need for new treatments, and for development of a possible vaccine for HCV. Now we have a model system to support work by investigators in this area."

Currently, there is only a single treatment for HCV, PEG- interferon-α. The drug combination has an average response rate of about 50 percent in HCV cases, but it is much lower than that, closer to 20 percent, in individuals with liver cirrhosis. It can also cause severe flu-like side effects. Approximately 10,000 deaths due to cirrhosis of the liver and several thousand more from liver cancer are attributed to HCV infection in the United States each year.

The HCV life cycle is only partially understood because, until now, it has not been possible to efficiently infect normal human hepatocytes, or liver cells, in culture. According to Buck, the valuable Huh-7 system currently in use to test HCV uses cloned, synthetic HCV RNA expressed from liver tumor cells. These cells cannot be infected with naturally occurring HCV obtained from infected patients.

In contrast, the culture developed by the UCSD scientists allows direct infection with HCV genotypes 1, 2, 3 and 4 from the blood of HCV-infected patients. This system will enable researchers to study the complete viral lifecycle in its normal host cell, providing novel scientific opportunities. The study reports that the system has been tested using over 30 virus donors as well as multiple donors of hepatocytes, with the production of infectious HCV for all genotypes tested.
-end-
This work was supported by grants from the National Institutes of Health, the Department of Veterans Affairs (Merit Review) and the Medical Research Foundation at UC San Diego. Buck is a recipient of the Howard Temin Award from the National Cancer Institute.

University of California - San Diego

Related Hepatitis Articles from Brightsurf:

Busting Up the Infection Cycle of Hepatitis B
Researchers at the University of Delaware have gained new understanding of the virus that causes hepatitis B and the ''spiky ball'' that encloses its genetic blueprint.

Liver cancer: Awareness of hepatitis D must be raised
Scientists from the University of Geneva (UNIGE) and the Geneva University Hospitals (HUG) have studied the most serious consequence of chronic hepatitis: hepatocellular carcinoma.

Hepatitis B: New therapeutic approach may help to cure chronic hepatitis B infection
Researchers at Helmholtz Zentrum München, Technical University of Munich (TUM) and the German Center for Infection Research (DZIF) have developed a novel therapeutic approach to cure chronic hepatitis B.

Anti-hepatitis medicine surprises
A new effective treatment of hepatitis C not only combats the virus, but is also effective against potentially fatal complications such as reduced liver functioning and cirrhosis.

Nanotechnology delivers hepatitis B vaccine
X-ray imaging shows that nanostructured silica acts as a protective vehicle to deliver intact antigen to the intestine so that it can trigger an immune response.

Checkmate for hepatitis B viruses in the liver
Researchers at Helmholtz Zentrum München and the Technical University of Munich, working in collaboration with researchers at the University Medical Center Hamburg-Eppendorf and the University Hospital Heidelberg, have for the first time succeeded in conquering a chronic infection with the hepatitis B virus in a mouse model.

How common is Hepatitis C infection in each US state?
Hepatitis C virus infection is a major cause of illness and death in the United States and injection drug use is likely fueling many new cases.

New strains of hepatitis C found in Africa
The largest population study of hepatitis C in Africa has found three new strains of the virus circulating in the general population in sub-Saharan Africa.

High stability of the hepatitis B virus
At room temperature, hepatitis B viruses (HBV) remain contagious for several weeks and they are even able to withstand temperatures of four degrees centigrade over the span of nine months.

Findings could lead to treatment of hepatitis B
Researchers have gained new insights into the virus that causes hepatitis B -- a life-threatening and incurable infection that afflicts more than 250 million people worldwide.

Read More: Hepatitis News and Hepatitis Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.