Interleukin-2 production in peripheral blood mononuclear cells of patients with gastrointestinal tumors.

Peripheral blood mononuclear cells of patients with different tumors of the gastrointestinal tract (esophagus, stomach, colon, rectum), with Crohn's disease and healthy controls were analyzed for their capacity to produce mitogen induced interleukin-2 (I1-2). Tumor patients could be divided into two groups, one group exhibiting a nearly normal and a second group showing a significantly decreased production of I1-2. Most of the patients with a carcinoma of the colon were found in the low-producer group. Patients with Crohn's disease did not significantly differ from the relevant controls. Tumor patients with proven metastasis produced less I1-2 as compared to those with localized disease although the differences are not significant. When I1-2 containing supernatants of patients with tumors were additionally analyzed for the presence of prostaglandin E2, an inverse relationship could be demonstrated. Supernatants showing a suppressed activity of I1-2 exhibited increased amounts of PGE2, indicating a modulation of I1-2 production by prostaglandin E2.