The complex role of mast cells in fungal infections.

In addition to their critical role in allergic disorders, mast cells (MCs) are well recognized for their protective effector functions during bacteria and parasite infections. This review describes recent advancements of our understanding of the complex role of MCs in fungal infections. Specifically, we outline key features of the contribution of MCs to infections with six fungal pathogens, namely Sporothrix, Paracoccidioides, Aspergillus, Malassezia, Candida and Dermatophytes. Evidence from studies of these pathogens suggests that MCs can function as positive regulators that detect and contain fungi at the site of infection. However, it appears that the inflammation induced by MCs following fungal infections may not always and only be beneficial to the host. MC responses during fungal infections may primarily benefit the pathogen by facilitating its spreading and contributing to a greater severity of fungal infections. This review also highlights key drivers of MCs activation and effector mechanisms that have been identified for the multidimensional function of MCs in fungal diseases and in allergic diseases combined with fungal infection.