Throughout evolution, our immune system has developed many ways to cope with invading harmful organisms. Recently, scientists have discovered another unusual way to stop the spread of a harmful fungus.
Our bodies have their own army to protect us from invaders and it seems that our white blood cells have a particularly clever way of fighting some fungi. A recent study conducted at Umeå University has provided a better understanding of this amazing defense mechanism, Tech Explorist writes.
The most common fungal pathogen is a fungus known as C. albicans. When it becomes too predominant, it can lead to nasty infections that can develop into sepsis in severe cases. White blood cells, in particular neutrophils, are our line of defense against this fungus. But sometimes simply killing fungi is not enough. Then a special trick of our white blood cells comes into play.
Neutrophils can secrete so-called neutrophil extracellular traps (NETs). Imagine a web created to catch and hold these fungi. In fact, this is an ETP, but with an additional effect. They contain sticky proteins that fight bacteria, which not only trap fungi but also actively fight them.
The study showed that when leukocytes come into contact with a certain toxin secreted by C. albicans, called candalisin, they begin to produce these NPs. But it is not just the toxin itself that causes this reaction. The cells have to recognize the fungus, then be exposed to the toxin – only then do they start releasing their nets in full force. Konstantin Urban, one of the researchers, expressed surprise at how effective these white blood cells were even after encountering the toxin.
But the scientists went even further in their study of this unique mechanism. They altered the shape of the C. albicans fungus and created a version that does not secrete the toxin candalisin. As a result of this manipulation, leukocytes did not secrete their special NPs. This shows how well tuned our body’s defense system is – it only uses its weapons when it reliably recognizes a serious threat.
So, how does this complex defense mechanism work? When candalisin interacts with white blood cells, it causes a reaction involving calcium. This reaction triggers a chain of events inside the cell. Eventually, this chain leads to the release of these NK cells, ready to capture and fight the invading fungus.
This study is the culmination of work by teams from Sweden, the UK and Germany. It offers valuable insights into our body’s defense mechanisms, which may lead to a better understanding and treatment of fungal infections in the future.
