Changes of enzyme activities recognized in lymphocytes from patients with carcinoma of the gastrointestinal tract.

Adenosine triphosphatase (ATPase) activity and acid phosphatase activity in lymphocytes from patients with carcinoma of the gastrointestinal tract were determined in order to investigate whether or not changes in these enzyme activities has any relation to the immune reactivity of carcinoma-bearing patients. In patients with a performance status of more than 60%, the mean value of the total ATPase activity in lymphocytes differed little from that in controls, but the mean value of the oligomycin-sensitive ATPase activity decreased as compared to that in the controls. On the other hand, the mean values of the activities of both free and total acid phosphatase in lymphocytes increased as compared to those in controls. The mean values of the activities of both ATPase and acid phosphatase in lymphocytes from patients whose performance status was less than 50% decreased as compared to those from controls and patients whose performance status was more than 60%. The change of the activities of both ATPase and acid phosphatase in lymphocytes has relation to that of the immunological parameters of the patients with carcinoma of the gastrointestinal tract. These results indicate that both ATPase and acid phosphatase in lymphocytes may play an important role in the immune mechanism.