Scientists from the Imperial College London have showcased how bacterial persister cells manipulate human cells, possibly opening new ways of clearing these bacterial cells from the human body, thus preventing recurrence of bacterial infection.
The latest findings published in the science journal help understand why few people suffer from repeated bouts of the disease even after taking antibiotics. The scientists studied Salmonella bacteria cells called persisters in their study which got the financial support from the Medical Research Council, the Lister Institute and EMBO (European Molecular Biology Organization). At any time, bacteria such as Salmonella infect the body; a number of bugs enter a type of standby mode in response to body immune attacks—antibiotics do not kill them.
These persistent bacteria cells discontinue their replication and can remain for days, weeks, or even months in this passive sleeper-cell state. When some of these bacterial cells spring back to life when antibiotic treatment is stopped, they may trigger another infection. Persistent cells form when macrophages absorb bacteria, which are human immune cells that contribute a major part in protecting the body from infections by engulfing viruses and bacteria.
Sometimes, the persister may take a state in which antibiotics will not be capable of killing it for weeks or even months inside the macrophage. Persisters were discovered in the early 19th century and were believed to be immobile, inactive bacteria settled low in the body, acting as a relapse time bomb. The scientists reveal in the latest research that the persistents, while hiding in the immune cells of the body, weaken the macrophage’s killing ability.
The researchers carried out work in collaboration with the Vogel laboratory at the Helmholtz Institute for RNA-based Infection Research in Germany, Helmholtz Center for Infection Research site. Although scientists studied mouse macrophage infection with Salmonella in their research, various types of bacteria commonly causing disease are known to form persistents in humans. The scientists are now investigating whether there is any way to turn the tables against the bacteria and whether they can target the mechanism that weakens immune cells in the human body through the persistent ones.