AI Summary
Researchers at the University of Louisville are studying Yersinia pestis, the bacteria that causes bubonic and pneumonic plague, to better understand its ability to evade the immune system. The bacteria hides from the immune system, allowing it to replicate and overwhelm the host. By understanding this evasion mechanism, researchers hope to control other pathogens.
When the body encounters bacteria, viruses or harmful substances, its innate immune cells, neutrophils, assemble at the site to combat the invader.
Bacteria and viruses have ways to avoid these defenses, however. Yersinia pestis, the bacteria that causes bubonic and pneumonic plague, for example, can hide from the immune system, allowing it to replicate in the body unhindered until it can overwhelm the host. This ability allowed Y. pestis to spread bubonic plague across Europe in the 14th Century, killing a third of the European population.
While plague may not be a serious threat to human health in modern times, researchers at the University of Louisville are studying Y. pestis to better understand its ability to evade the immune system and apply that understanding to control other pathogens.
If you look at human plague, people don’t show symptoms right away even though they have an active infection because the bacteria is hiding from the immune system. Then all of a sudden there is a lot of bacteria, the immune system is overwhelmed and in the case of pneumonic plague, the individual dies from pneumonia.”
Matthew Lawrenz, Professor, UofL Department of Microbiology and Immunology
Neutrophils are the immune system’s first responders, sending out protein molecules to summon other neutrophils to attack and destroy the invader. Among the first molecules sent out by neutrophils to signal an infection are Leukotriene B4 (LTB4) lipid molecules. Y. pestis interferes with the immune response by suppressing the LTB4 signals. Lawrenz has