[Oral administration of OK-432 (picibanil). (8th report) clinical application: its immunomodulatory effects on the patients with gastrointestinal cancers].

A streptococcal preparation, OK-432 at a dose of 5 KE was orally administered to the patients with gastric or colorectal cancer for 7 approximately 14 days before operation, and its immunomodulatory effects on peripheral blood lymphocytes (PBL), regional lymph node lymphocytes (RLNL) and tumor infiltrating lymphocytes (TIL) were assessed. OK-432 treated group included 5 gastric and 6 colorectal cancers, and control group included 6 gastric and 8 colorectal cancers. After oral administration of OK-432 the proportion of Leu 7+ and Leu 11+ cells in PBL increased, and NK cell activity of PBL also was augmented. The proportion of OKT8+ cells increased in PBL and those of OKT3+ cells and OKT8+ cells decreased in RLNL after oral administration of OK-432. The responsiveness of TIL to autologous tumor extracts in the presence of interleukin-2 was enhanced in oral OK-432 group. These results indicate that oral OK-432 affects on NK and T cells and augments the antitumor immunity of the patients with gastrointestinal cancer.