Candida fungi can burst immune cells and shape-shift to evade immunity

Candida fungi, microscopic pathogens responsible for lethal infections, are able to kill immune cells and adapt to evade immunity, posing significant global health threats. The World Health Organization has identified these species as among the most concerning, with growing outbreaks in Europe and the United States. New research from Monash University, published in Nature Communications and Nature Microbiology, reveals the mechanisms behind these fungi's survival strategies and offers potential solutions.

The study highlights a crucial amino acid, alanine, that can reverse the process by which Candida fungi evade the immune system. When immune cells engulf a fungal microbe to destroy it, the fungus fights back from within, triggering host proteins to form pores that cause the immune cell to burst and release the fungal cells, allowing the infection to spread. By providing a higher dose of alanine, researchers successfully blocked this process, preventing immune cell rupture and containing the fungal cells.

First author Dr Harshini Weerasinghe explains that keeping the pathogen trapped in a cellular bottleneck would ensure it can be more effectively contained and targeted. This approach may offer a novel treatment strategy in conjunction with antifungals to eradicate the infection. The research also sheds light on Candida auris, a particularly dangerous strain that can change its shape and stick to human tissue, evading detection by immune cells.

In the bloodstream, it consumes glucose and adopts a long, sticky form that allows it to attach and persist undetected.

Understanding how Candida auris modulates its shape and properties according to available nutrients could lead to novel treatment options. By monitoring the types of sugars present in human tissue, the fungus can adapt to its environment, making it difficult to eradicate. Senior author Professor Ana Traven emphasizes the importance of this research in the face of changing environmental and economic conditions.

With few traditional antifungals available and pharmaceutical companies focusing on less profitable drug categories, researchers are exploring nutritional manipulation of the patient's body to strengthen the immune system's ability to fight back against these resilient pathogens.