We breathe in 10 billion fungal spores every day, but we don't die. How it works?

The humid and warm environment inside the human lungs is great for the reproduction of fungi, and they have long learned to settle there. Every day, a person inhales between 1, 000 and 10 billion spores, but instead of waging a merciless war with them, our immune system gracefully forces the spores to commit suicide. Alas, this unique mechanism has become increasingly malfunctioning and scientists are trying to figure out what can be done about it.

When spores enter the body, they are attacked by neutrophils - highly mobile immune cells, the first line of defense. However, they do not fight spores directly, but trigger apoptosis or programmed cell death in them. The basic mechanism that allows a hopelessly damaged, unable to reproduce cell, die "with honor", making room for the rest. But the disputes are still quite alive and well?

To test the hypothesis, scientists added a special coding protein "Survivin" to the DNA of the spores, which blocks the mechanism of programmed death in human cells. The test mice infected by them died in agony - in their lungs the spores survived, germinated and caused severe tissue destruction. To consolidate the success, scientists injected mice with a drug to block the already protein Survivin and everything returned to normal - neutrophils again successfully provoked suicide in disputes.

After studying how spores with Survivin resisted neutrophils, the scientists drew attention to the release of the enzyme NADP, a common catalyst for oxidative reactions. Spore cells think they are in a stressful environment, on the verge of death, and self-destruct. But the trouble is, the production of this enzyme by the human body is unstable and is increasingly weakened by genetic defects, the effects of drugs, and the consequences of past infections. Such patients are at risk - today scientists are struggling to create an alternative way to destroy spores in the lungs of people.