Prof. Dirk Bumann’s research group at the Biozentrum of the University of Basel has now uncovered how the typhoid pathogen repeatedly manages to evade the host’s immune system. Their findings are published in the scientific journal “Cell Host & Microbe”.
Salmonella-infected cells (macrophages in blue, monocytes in turquoise). Dead Salmonella (only yellow), surviving Salmonella (yellow and red).
Illustration: University of Basel
Typhoid fever is a bacterial infection caused by the pathogen Salmonella. The infected host’s immune system detects Salmonella and activates immune cells such as neutrophils and monocytes. These cells infiltrate the infected tissue and enclose the infection to form an abscess. Although most Salmonella bacteria are readily killed by this immune reaction, Dirk Bumann’s group has demonstrated that some escape from the abscess and thus ensure their survival.
Salmonella uses immune cells
Once outside the abscess, the Salmonella bacteria are attacked by other immune cells, the so-called macrophages that produce a less effective immune response. “Salmonella have developed a range of defense strategies to resist macrophage attacks. Many Salmonella are thus able to survive and even to replicate in macrophages,” explains Neil Burton, one of the two first authors. With time, abscesses form around the new infection foci but again some Salmonella bacteria can manage to escape.
“This drives the whole infection process further and makes typhoid fever particularly insidious,” says Nura Schürmann, also a first author of the publication.
A battle on many fronts
The whole disease process is a race between Salmonella and the immune system of the infected organism, in which the battle is fought on many fronts. In this process many Salmonella bacteria are killed and others survive to spread the infection. It is the net balance of the outcomes of these individual Salmonella and immune cell encounters which in the end determines the course of the illness.
Typhoid fever is a life-threatening infection in countries with poor hygiene. Each year, more than 20 million people are infected with this disease. The illness is transmitted by ingesting food or water contaminated with this bacterium. Once inside the intestine, Salmonella crosses the gut mucosa and spreads to other organs such as the spleen and liver. Growing antibiotic resistance makes this illness increasingly difficult to cure.
Understanding what factors enable Salmonella to win many encounters with host cells might provide new strategies in the treatment of typhoid fever. Similar heterogeneous encounters likely determine the fights between the host and many other pathogens. Findings of this study may thus be relevant for a wide range of infectious diseases.Original Citation
Olivia Poisson | Universität Basel
Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery
20.01.2017 | GSI Helmholtzzentrum für Schwerionenforschung GmbH
Seeking structure with metagenome sequences
20.01.2017 | DOE/Joint Genome Institute
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
20.01.2017 | Awards Funding
20.01.2017 | Materials Sciences
20.01.2017 | Life Sciences