Development of an enzyme-linked immunosorbent assay to detect an immunomodulatory alpha-D-glucan-protein complex, MPG-1, in basidiomycete Tricholoma matsutake and related processed foods.
We previously isolated a novel immunomodulatory alpha-(1,4)(1,6)(1,2)- d-glucan-protein complex (MPG-1) from mycelia of Tricholoma matsutake in basidiomycetes. In the present study, we raised a polyclonal antibody by immunizing rabbits with MPG-1 and constructed a sandwich enzyme-linked immunosorbent assay (ELISA) system to examine the distribution of MPG-1 among edible mushrooms and related processed foods. The system detected MPG-1 quantitatively at concentrations of more than 10 ng/mL, with a coefficient of variation of less than 10% by intra-assay and interassay precision. Analysis with the system of chemically modified MPG-1 suggested that the sugar moiety was mainly involved in the detection. The system detected MPG-1 in the extracts of the fruiting bodies of T. matsutake but not in those of 34 other basidiomycete species. Moreover, a significant amount of MPG-1 was detected in the extracts of their cultured mycelia. The antigenic structure of MPG-1 was relatively stable in terms of pH and temperature. MPG-1 was detected in processed foods supplemented with T. matsutake. These results suggest that MPG-1 is distributed predominantly in T. matsutake species and that the ELISA system can detect it in processed foods supplemented with T. matsutake.
Hoshi
Hirotaka
H
Biomedical Research Laboratories, Kureha Corporation, 3-26-2 Hyakunin-cho, Shinjyuku-ku, Tokyo 169-8503, Japan. h-hoshi@kureha.co.jp
Yagi
Yoko
Y
Matsunaga
Kenichi
K
Ishihara
Yoko
Y
Yasuhara
Tadashi
T
D000818:Animals; D001487:Basidiomycota / Q000737:chemistry*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005260:Female; D048690:Fruiting Bodies, Fungal / Q000737:chemistry; D005656:Fungal Proteins / Q000032:analysis* / Q000276:immunology; D005936:Glucans / Q000032:analysis* / Q000276:immunology; D007155:Immunologic Factors / Q000032:analysis*; D025282:Mycelium / Q000737:chemistry; D010455:Peptides; D011817:Rabbits; D012680:Sensitivity and Specificity
D005656:Fungal Proteins; D005936:Glucans; D007155:Immunologic Factors; C516249:MPGalpha peptide; D010455:Peptides