[Preoperative immunotherapy in patients with gastric cancer--with special reference to analysis with monoclonal antibodies of T-lymphocyte subsets and interleukin-2 oral administration of OK-432 (Picibanil)].

The effects of oral administration of OK-432 on immune reactivities of gut associated lymphoid tissue (GALT) were studied in patients with gastric cancer. The lymphocytes of peripheral blood, regional lymph nodes and spleen in patients with gastric cancer were measured by using different monoclonal antibodies and flow cytometry. OKT3, OKT4, OKT8, OKM1, OKT4+2H4+, OKT4+2H4-, OKT8+Leu15+ and OKT8+1Leu5- were used as monoclonal antibodies. The NK activity, Interleukin-2 production and Interleukin-2 receptor were also measured. After oral administration of OK432, 1) little change was found in peripheral blood and spleen, 2) the percentages of OKT3, OKT4, OKT4+2H4- and the ratio of OKT4/OKT8 were increased in proximal regional lymph nodes, and 3) the percentages of OKT8 and OKT8+Leu15- in regional lymph nodes were not changed. These results suggest that the helper T cell activity and the antitumor immunity of regional lymph nodes were elevated by oral administration of OK-432.