Expression of interleukin‐6 and tumor necrosis factor in peritoneal mononuclear cells after gastrectomy

Abstract

As macrophages are found in peritoneal exudates after abdominal surgery, interleukin-6 and tumor necrosis factor-alpha, their messenger RNAs and immune-specific proteins would also be expected to be found in both peritoneal fluid and mononuclear cells under such conditions. The peritoneal fluid and plasma of patients who had undergone gastrectomy were investigated on postoperative days 1, 3, 5, and 7. Evidence of mRNA expression and the intracellular immunocytochemical localization of interleukin-6 and tumor necrosis factor-alpha was determined in cells isolated from peritoneal fluid, and immune-specific protein levels in the peritoneal fluid were measured. Both interleukin-6 and tumor necrosis factor-alpha proteins were identified immunocytochemically in the cytoplasm of peritoneal mononuclear cells, and their mRNAs were detected by the reverse transcriptase-polymerase chain reaction. The concentration of interleukin-6 in the peritoneal fluid was significantly higher than that in the plasma, and a high level of tumor necrosis factor-alpha was found in the peritoneal fluid, despite its absence from plasma. Expression and changing levels of interleukin-6 and tumor necrosis factor-alpha in human peritoneal fluid after gastrectomy were shown, indicating local production of these cytokines, which may play important roles in tissue repair.