الفهرس 
Physiology of the noseOnly 14 pages are availabe for public view
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Abstract
Anti fungal host defense is mounted by both innate and adaptive wings of the immune system. Innate immunity appears to play a very important role in effecting anti fungal immune response, and in most cases, is central to the clearance of fungal pathogens in immunocompetent individuals.
Innate immunity comprises the barrier functions of mucosal epithelial surfaces, microbial antagonism by normal flora, complement activation and opsonization of invading pathogens as well as participation of a variety of cells with antigen-presenting and phagocytic activity such as dendritic cells, mononuclear leukocytes (macrophages and monocytes) and neutrophils.
Recognition of fungal structures (conidia, hyphae) by host cells occurs through binding of fungal cell wall components (pathogen-associated molecular patterns) to pattern-recognition receptors (PRRs) on the surface of host cells; PRRs include Toll-like receptors (TLRs) mainly TLR2 and TLR4, C-type lectins.
Antifungal activity of host phagocytic cells is mediated by both oxidative and nonoxidative mechanisms. Oxidative damage occurs through release of reactive oxygen intermediates by NADPH oxidase and nitric oxide synthase. The nonoxidative mechanisms involve the release of defensins and other antimicrobial peptides.
Apart from exerting antifungal activity, innate immunity host cells and particularly dendritic cells serve as major antigen-presenting cells and inducers of adaptive T-cell responses.
The innate immune system is an active participant at the nasal tissue level and changes in its responses and effects to pathogens affects the adaptive immune system.
This complex interplay between the innate and adaptive immune systems is only now being recognized, with further research into innate immune responses required to understand its role in fungal sinusitis.
Adaptive immune responses against fungi start to mediated through differentiation of CD4+ T cells in two pattern, towards a protective T-helper type 1 (Th1) or non protective T-helper type 2 (Th2) phenotype. Th1 responses involve the production of Th1 cytokines resulting in stimulation of phagocytic activity, generation of cytotoxic CD4+ and CD8+ T cells, production of opsonizing antibodies and an overall protective effect against fungal pathogens.
Th2 responses are mediated through Th2 cytokines, which down-regulate the action of Th1 cytokines, resulting in attenuation of protective effects and development of allergic manifestations in response to inhaled conidia of various molds.