Sunday, 6 March 2016

Molecular switch lets salmonella fight or evade immune system


Researchers at the University of Illinois at Chicago have discovered a molecular regulator that allows salmonella bacteria to switch from actively causing disease to lurking in a chronic but asymptomatic state called a biofilm.

Biofilms cling to surfaces in the body, such as the bronchial tubes or artificial joints, often without causing illness. But they can be a reservoir of bacteria that detach and cause disease or infect new hosts. The biofilms are resistant to host defenses and antibiotics because their tightly-packed structure exposes little surface area for drugs to reach. Many pathogenic bacteria are able to switch from an infectious to a dormant state as a strategy for survival inside their hosts.

Linda Kenney, professor of microbiology and immunology at the UIC College of Medicine and lead author of the study, had been studying how salmonella survive inside immune system cells called macrophages. These white blood cells patrol the body and engulf viruses and bacteria they encounter. They encase their prey in a bubble called a vacuole that protects them from the invader until it can be destroyed.

For more on this story, see Phys.org



 Posted by Dr. Tim Sandle