Mechanism of IFN-γ Induction using Fungal Immunomodulatory Protein Regulated T Helper Cell Differentiation as Healthy Food Application to Alleviate House Dust Mite Induced Asthma

FIP-fve is a protein that is isolated from Flammulina velutipes. Its known immunomodulatory activities are elicitation of the production of type II interferon from human peripheral mononuclear cells (hPBMCs) and hemagglutination. How the target receptors mediate activation of FIP-fve-induced immunomodulatory effects remains to be elucidated. This study postulates the three-dimensional structures to determine whether the carbohydrate binding module family 34 (CBM-34) on FIP-fve is conserved to site N of Thermoactinomyces vulgaris R-47 α-amylase I. Experimental site-directed mutagenesis data as well as ligand-specific binding competition assay are adopted to identify the key residues W24, T28, D34, T90, I91, and W111 of FIP-fve that participate in binding to polysaccharides that are linked to the membrane of immune cells. Treatments of hPBMCs with tunicamycin and deglycosylation enzymes that removed the carbohydrate moieties reduced the secretion of IFN-γ induction from hPBMCs. Furthermore, we used next generation sequencing (NGS) technologies to identify especially the Dermatophagoides Microceras (Der m 2, MW 14,000) allergen which can estimate of the major specificities of allergens which are potent inducers of IgE synthesis favoring Th2 response involved in type I hypersensitivity. Analyzing NO and inflammatory cytokines induced by GST-Der m 2 in alveolar macrophages, we found that FIP-fve could retard NO production but no effects on TNF-α production. In conclusion, this investigation provides a greater rationale of the mechanisms that development of associated FIP-fve to the clinically relevant allergen House Dust Mites provided scientific evidences supported immune modulatory effects in the prevention of allergic diseases and may be as health food products.