Enhancement of immune reactivities of regional lymphnodes by oral administration of OK-432 in colon cancer patients

Abstract

Effect of oral administration of OK-432 on the immune reactivities of regional lymphnode (RNLs) and peripheral blood lymphocytes (PBLs) in colon cancer patients were investigated. Twenty KE of OK-432 was given orally on 7 days prior to the operation, and peripheral blood and regional lymphnodes were collected at the time of operation. As for the immune reactivities of PBLs such as lymphocyte proliferative response to phytohemagglutinin (PHA), natural killer (NK) cell activity and Concanavalin A (Con-A) induced suppressor cell activity, there were no significant differences between patients with oral OK-432 (OK-432 (+) group) and those without OK-432 (OK-432 (-) group). NK cell activity of RLNs was significantly higher in OK-432 (+) group than in OK-432 (-) group. Furthermore, the decline of Con-A induced suppressor cell acivity was found in OK-432 (+) group. T cell subsets in regional lymphnode tissues were identified with the use of monoclonal antibodies and immuneperoxidase technique. Both of Leu-2 a and Leu-7 positive cells distributed more frequently in lymphnodes from OK-432 (+) group than in those from OK-432 (-) group. Thus, these results suggested that immune reactivities of regional lymphnodes were en-hanced by oral administration of OK-432 in colon cancer patients.