Pathogens: immune cells against stubborn viruses

Virus infections are not only common in times of pandemic. Not all viruses that affect humans actually make us sick. The immune system often reacts quickly and successfully fights off intruders. However, some pathogens can overwhelm the immune system. Researchers are now reporting what may help against stubborn viruses.

as it is at present Message The University of Basel states that viruses such as the pathogens causing HIV or hepatitis C can overwhelm the immune system. One approach to develop vaccines against such chronic infections has so far targeted the immune system’s so-called B memory cells. Researchers at the University of Basel have now discovered that these cells need the help of other memory cells to effectively protect the organism against chronic viruses.

protection against pathogens

A vast arsenal of immune cells defends the organism against pathogens. In the event of virus infection, B cells produce appropriate antibodies that neutralize the pathogen. Some of these B cells die again after infection or vaccination, but some B cells remain in the body as memory cells to produce the correct antibodies more quickly when the same pathogen is reinfected. Vaccines target the formation of these B memory cells, among other things.

But viruses such as HIV or the hepatitis C virus overwhelm the defenses of B memory cells — a barrier to the development of efficient vaccines. To overcome this obstacle, scientists have appointed Prof. Dr. Daniel Pinschever from the Department of Biomedicine at the University of Basel investigates the interaction of immune cells in chronic viral infections.

“One problem is that B memory cells elicit a kind of panic response given the constant presence of the pathogen and the associated inflammation,” Pinschever explains. By a program of reproduction and maturation, they are all changed in the mode of antibody production and are quickly destroyed. The research team is now reporting on potential treatments for this problem in a specialist journal.”PNAS,

stop panic reaction

For their experiments, the researchers studied infection of mice with a mouse virus called lymphocytic choriomeningitis virus (LCMV), which causes chronic infections in animals. They found that B memory cells require the help of other immune cells for an enduring response to the virus: namely T helper memory cells, whose formation can also be triggered by appropriate vaccination strategies.

If the scientists induced the formation of appropriate T helper memory cells in test animals prior to LCMV infection, the latter prevented the panic response of B memory cells after infection.

“Instead of wasting the entire stock of B-cells in the unsuccessful fight against the virus, thanks to the T-helper memory cells, there remains a reserve of B-cells, which continually multiply and mature and enhance the defense against the virus.” maintains”, explains Dr. Kerstin Naar, lead author of the study.

Until now, the role of T helper memory cells in vaccination against chronic viruses has not been adequately taken into account. “The knowledge that these cells can be used to promote a more sustained immune response through B memory cells has direct relevance for strategies to develop new vaccines against HIV and hepatitis C,” Pinschever said. said. (advertisement)