Hepatitis-B-virus-protect yourself with a cloak of invisibility from immune response

Hepatitis B is widespread. Around 250 million people worldwide are chronically infected with the Virus. An infection increases the risk for the development of liver cirrhosis and liver cancer. The Transmission is via body fluids (for example, through sexual intercourse). A German research team explained why our immune system has great difficulty in fighting the Virus.

Researchers from the Paul-Ehrlich-Institut have studied, in collaboration with other research groups, such as Hepatitis B virus (HBV) evade the defense by the immune system. This showed that the Virus is a true specialist of the camouflage. The results of the research were recently presented in the journal “Viruses”.

How the body responds to pathogens

Our immune system is a body’s own defense system against invading disease represents pathogens. In this case, the immune system reacts to the so-called pathogen-associated molecular pattern (PAMP) that are typical for pathogens. Such patterns are recognized by specific receptors (pathogen recognition receptors), which trigger signaling pathways and the immune response set in motion.

Cops and robbers

For most viruses the molecular pattern that is recognized by the receptors, the genetic Information of the Virus, i.e., the ribonucleic acid (RNA) or deoxyribonucleic acid (DNA). One possible defense mechanism of the virus, inter alia, to inhibit the triggered signalling pathways or the genetic information to be shielded, so that they will not be recognized by the immune system.

Hepatitis-B-virus are not sufficiently researched

The Team criticized the treatment of chronic HBV infection is limited as before to keep long-term use of Antivirals, the viral load is low and the health effects as low as possible, although the disease has been known for a long time. A fundamentally curative therapy is not available. This was mainly due to the fact that still not enough is understood about how the Virus eludes so successful in the defense of the immune system.

The camouflage is busted

The research group of Dr. Renate König is the solution to this puzzle is now one step closer. The researchers showed in experiments that the immune system is theoretically capable of a strong reaction as soon as it detects the DNA of the virus. At the same time, the Team found that this pathway is not activated in the case of an actual HBV infection, although the Virus seems to him to actively suppress.

The results suggest that the shell of the virus, called capsid, that protects the DNA before detection. A possible approach to treatment is therefore, the capsid of the virus attack, in order to make it visible, so that it can be eliminated by the immune system, says the research team. (vb)

Authors and source of information