Mold fungus infections For this reason, mold is so dangerous

This is how a mold breaks down the immune system

Mold fungi often also nest in our domestic living quarters, which brings with it considerable health risks. A research team led by Professor dr. Oliver Werz from the Friedrich-Schiller-University Jena has now found out how the fungus Aspergillus fumigatus thwarts the immune system and can lead to life-threatening fungal infections.

Mold fungi often cause serious illnesses, especially in people who are already weakened, and these are often life-threatening. A particularly common representative of the genus of mold fungi is Aspergillus fumigatus. Why this can easily become a serious danger to people, the international research team led by Professor Werz examined in a recent study. Their results were published in the journal "Cell Chemical Biology".

Molds are practically everywhere

Aspergillus fumigatus can be found almost everywhere and highly dangerous for people with weakened immune systems, the researchers report in a press release from the University of Jena. The fungus "occurs in virtually all habitats of the earth: as a dark gray, wrinkled pad on damp walls or in microscopic spores that fly through the air and adhere to wallpaper, mattresses and floors." For most people, this is not a particular problem because their immune system can successfully ward off or eliminate the spores. However, in individuals with immunodeficiency, the body's immune system is unable to successfully eliminate mold spores invading the organism. It can quickly put the fungus in mortal danger.

Mycotoxin weakens the immune system

The international research team has been able to prove in its investigations that among other things the so-called gliotoxin, a highly potent mycotoxin, has a significant influence on the pathogenicity of the mold. "It was known that this substance is immunosuppressive, that is, weakens the activity of immune system cells"; explains the study leader Prof. Werz ... In the current study, the researchers have now investigated how exactly gliotoxin influences the immune system. They were able to detail the underlying molecular mechanisms.

Effect on immune cells examined

In their study, the researchers have linked immune cells, called neutrophilic granulocytes, with synthetically produced gliotoxin and observed the reaction. These cells form the first immune defenses of the immune system, explain Prof. Werz and colleagues. "Their job is to detect and eliminate pathogens," the study director continued. When neutrophilic granulocytes come into contact with a pathogen such as a fungus, they release certain messenger substances (leukotrienes) into the blood, which attract more immune cells. Thus, a sufficiently large number of immune cells can assemble to render the intruder harmless, reports Prof. Werz.

Communication of the immune cells is prevented

However, the pathogen Aspergillus fumigatus shuts off the protective mechanism by means of gliotoxin. This prevents the production of the messenger substance LTB4 in the neutrophilic granulocytes, whereby the immune cells can not give a signal to other immune cells, explain the researchers. The mycotoxin shuts off a specific enzyme (the LTA4 hydrolase) and "thus the communication between the immune cells is interrupted and the defense mechanism is disturbed," says Professor Werz. In this way, invading germs, in this case the mold fungus, can easily nest in tissues or organs and, under certain circumstances, cause a life-threatening invasive fungal infection. (Fp)