Researchers at the Weizmann Institute of Science have identified a novel yeast species that could potentially prevent invasive candidiasis, a major cause of death in hospitalized and immunocompromised patients. Their study, published in the Journal of Experimental Medicine, found that the novel yeast, Kazachstania weizmannii, lives harmlessly in the intestines of mice and humans and can displace the yeast responsible for candidiasis, Candida albicans.
Millions of microbial species live within or on the human body, many of them being harmless or even beneficial to human health. C. albicans is commonly found in the intestines and other mucosal surfaces of the body and is usually benign, though occasionally it may overgrow and cause superficial infections. However, under certain circumstances, the yeast may penetrate the intestinal barrier and systemically infect the blood or internal organs, leading to invasive candidiasis, which is commonly seen in healthcare environments, particularly in immunocompromised patients, with mortality rates of up to 25%.
The researchers discovered that K. weizmannii can outcompete C. albicans for its place within the gut, reducing the population of C. albicans in mouse intestines. Moreover, while C. albicans can cross the intestinal barrier and spread to other organs in immunosuppressed mice, the presence of K. weizmannii in the animals’ drinking water significantly delayed the onset of invasive candidiasis. Notably, the researchers also identified K. weizmannii and other, similar species in human gut samples, suggesting that the two species might also compete with each other in human intestines.