New mechanism could result in treatment for hepatitis B

A newly discovered mechanism could allow for new avenues for treating hepatitis B that do not damage infected liver cells, according to a study recently published in Science.

While available antiviral medicines are able to control the hepatitis B virus, they are unable to completely eliminate it. HBV persists by depositing DNA in the liver cell's nucleus. The virus is reactivated when treatment is discontinued.

A team of German researchers found a way to selectively attack the viral genetic information in the cell nucleus of liver cells without damaging the host cell.

"The degradation of viral DNA in the cell nucleus that we describe represents an important mechanism in the defense against the virus," Ulrike Protzer, one of the researchers, said. "Moreover, for the first time, the results offer the possibility to develop a treatment that can heal hepatitis B."

The scientists found that activating the lymphotoxin β receptor in the host cell, certain proteins are promoted in such a way that they chemically degrade and change hidden viral DNA known as covalently closed circular DNA. This keeps HBV from reactivating and prevents the disease from breaking out even after the end of treatment.

The researchers said the proteins do not change the genetic information of the host liver cell itself.

"With the activation of the lymphotoxin β receptor, also combined with substances that are already available, we have a very promising new therapy concept available," Mathias Heikenwälder, another researcher on the project, said.

According to the World Health Organization, more than 240 people worldwide are suffering from a chronic hepatitis B infection.