Immunomodulators: Potential in Treatment of Systemic Fungal Infections

Abstract

Innate immunity mediates strong resistance to fungal pathogens and contributes to host defense against opportunistic fungal infections such as candidiasis, aspergillosis, and other rare infections. Immune factors such as cytokines and effector immune cells work synergistically with antifungal agents to restrict fungal growth. However, in immunocompromised hosts, the defectiveness of immune functions that should cooperate with antifungal drugs to clear the pathogens seems to be a critical factor that impedes the effectiveness of these drugs. The renovation or augmentation of immune responses is now considered as one of the foundations of effective antifungal therapy. Immunomodulation represents a novel approach to antimicrobial therapy that depends on boosting host immunity, rather than direct antimicrobial activity. Immunopotential therapy therefore offers a rational approach to the treatment of fungal infections, because it is intended to enhance immune functions in general. Major advances in the field of experimental immunology have provided insight into the important regulatory role of cytokines in both innate and adaptive immunity to fungal pathogens. Exploration has also begun with immunotherapy, with use of cytokines and immunomodulators alone or in combination with antifungal therapy. The administration of cytokines to patients, together with antifungal agents, offers promising immuno-therapeutic modalities for further research. The diverse array of natural, synthetic, and recombinant immunomodulators discussed in this chapter succinctly demonstrates the potential of these agents to stimulate host defense mechanisms for prophylaxis and treatment of various fungal infections.