Immune Response to Fungal Pathogens

Abstract

Fungi rarely cause disease in individuals with normal immunity. However, fungi present in the normal biota of the skin, mucous membranes, intestinal tract, and fungi in the environment that are normally non-pathogenic, can cause life-threatening infections in individuals with suppressed immunity. In the past decades, the prevalence of opportunistic fungal infections has increased, and these are associated with lowered immunity due to chemotherapy, HIV infection, and aging. The development of traditional antifungal agents has not kept pace with the increasing prevalence of invasive fungal infections, and the resistance to antifungal agents has become a major problem. Fortunately, study of the molecular and cellular mechanisms of the host immune response to fungi is increasing day-by-day. These studies indicate that fungal-specific mechanisms exist in the human body, including maintenance of immunological homeostasis in tissues, destruction of homeostasis by fungal infections, elimination of fungi by the host immune response, and recovery of homeostasis. Research into the mechanisms of fungal infection in humans suggests a new treatment paradigm that goes beyond traditional antifungal agents. Vaccines against fungi and immunotherapy using the host immune mechanism against fungi have recently been developed and are nearing use in the clinic.