How does hepatitis E fool the immune system?

An international team led by the Department of Molecular and Medical Virology at the Ruhr-Universität Bochum in Germany investigated factors important to Hepatitis E (HEV) in the context of a recurrence cycle And how to keep infection.

In their work published in the scientific journal PNASThe researchers analyzed the different mutations of the virus and Changes found that could allow the virus to trick the immune system. More than three million people are infected with the hepatitis E virus each year. So far there is no effective treatment against this disease.

Antibodies are an important defense mechanism against viral infections in our bodies. They specifically bind to the surface proteins of viruses to make them harmless. But Viruses have developed strategies to evade this neutralization.

Hepatitis C virus mutations, keys to evading the immune system

During infection with hepatitis E virus, Random mutations often result in different types of virus that can coexist in an infected person. The antiviral agent ribavirin, which many patients with chronic infections receive, can increase the formation of such variants.

research team She closely examined eight different types of capsid protein From samples of patients with chronic infection treated with ribavirin in vitro. The team wanted to know what genetic changes are advantages or disadvantages of the virus and whether they affect the virus’s ability to reproduce or infect.

“While seven of the mutants examined behave exactly like the wild-type virus, We found differences in the mutant,” explains Tony Louise Meister, one of the study leaders.

This mutation affects the capsid protein, which is essential for mobilization of viral particles. “Viruses with this mutation are improperly assembled, and may be smaller than wild-type viruses.The capsid protein does not accumulate in the cell,” commented another author, Daniel Todd.

These particles are not contagious, but They are correctly identified and associated with antibodies to the immune system. Eike Steinmann, the last author speculates: “This could be beneficial to the virus. These defective particles can absorb the antibodies, so that there is no longer enough to neutralize the properly assembled infectious virus particles.”

Hepatitis E, dangerous in immunosuppressed patients

Hepatitis C virus is the main cause of acute viral hepatitis. Every year about 70,000 people die from this disease. After the first documented outbreak of the epidemic between 1955 and 1956, it was more than 50 years before researchers addressed the topic.

acute infections It tends to heal on its own in individuals with a healthy immune system. In patients with weakened or compromised immune systems, such as organ transplant recipients or patients with HIV, HEV can become chronic. HEV is especially dangerous for pregnant women.