The Missing Link between Candida albicans Hyphal Morphogenesis and Host Cell Damage

Fungal pathogens are more commonly associated with morbidity and mortality than generally appreciated. In fact, a significant portion of the world population is infected by fungi, and an estimated 1.5 million people die from life-threatening fungal infections each year [1]. One of the most common fungal pathogens of humans is Candida albicans. The majority of the human population is colonised with this fungus, and superficial infections of mucosal surfaces are extremely common [2].

The morphological plasticity of C. albicans has long been implicated in the virulence of this pathogen [3]. The two most important morphologies, yeast and hyphal cells, are both required for virulence. Neither yeast-locked strains nor hyperfilamentous mutants are fully virulent in experimental systemic infections. However, it is generally accepted that each of the two forms fulfils specific functions during infection. While the yeast form is likely important for dissemination via the blood stream, the formation of filamentous hyphae contributes to adhesion and invasion of host cells.