[#1990-03] Antitumor Effect of Orally Administered Extracts from Fruit Body of Grifola frondosa (Maitake), Y. Yamada et al.

Antitumor Effect of Orally Administered Extracts from Fruit Body of Grifola frondosa ( Maitake )

Yamada, Y, Nanba, H, Kuroda, H

Laboratory of Microbiology, Kobe Women’s College of Pharmacy

We conducted a footpad swelling test to clarify whether a delayed-type hypersensitivity (DTH) reaction against tumor antigen is potentiated by oral administration of D-fraction extracted and purified from fruit body of Grifola frondosa (maitake) with a ratio of β-glucan to protein of 7:3. When the antigen was injected in D-fraction administered tumor-bearing mice (D-mice), footpad swelling was observed, suggesting that a DTH reaction against the tumor antigen was potentiated by oral administration of D-fraction. Winn assay was carried out with whole spleen cells from D-mice and Lyt-2- spleen cells in which Lyt-2+ cells corresponding to cytotoxic T cells (CTL) were eliminated by treating with anti-Lyt-2 monoclonal antibody and complement. Even after CTL were eliminated, tumor neutralizing activity was at no time impaired, indicating that spleen cells other than CTL play a leading role in tumor cytotoxicity.

We hypothesize from the above results, that a DTH reaction, manifested by the combined action of delayed hypersensitivity T cells (Tdh) and macrophages was potentiated by oral adminstration of D-fraction. Even when CTL are absent, there is a high degree of tumor involution. But D-fraction did not activate gut-associated lymphoid tissue (GALT) and Peyer’s patch (PP) by oral administration.