A food pathogen, Listeria monocytogenes, causes a severe illness (listeriosis) that can infect our central nervous system (neurolisteriosis). This infection is fatal in 30% of all cases! The question is: how can Listeria monocytogenes escape from our immune system defense and get into the most protected area of our body, our brain?

This question was investigated in a recent study. The researchers found how Listeria monocytogenes infects the central nervous system and then developed an experimental model using virulent strains of Listeria (isolated from people with neurolisteriosis), and mice that reproduces the different stages of human listeriosis. They discovered an unexpected escape mechanism by which a pathogen increases the life span of the infected cells by specifically blocking an immune system function that is crucial for controlling infection. This escape mechanism allows the infected cells (inflammatory monocytes) to live longer, infect other cells in the blood, and facilitate bacterial spread to different tissues. In case of the brain, the infected cells adhere to the brain vessels’ cells, enabling Listeria to cross a barrier and infect the brain tissue.

Researchers assume that other pathogens such as Toxoplasma gondii and Mycobacterium tuberculosis, might use similar mechanisms to infect the brain.

Curious? HERE is the source