Autologous serum deprivation restored IL-1 receptor antagonist production by peripheral blood mononuclear cells in patients with gastric cancer

It has been established that cancer patients have immunosuppressive substances in their sera that depress cellular immunity. Although plasma exchanges have been attempted to remove these substances and to improve immunity to cancer, little is known about its mechanism from the viewpoint of cytokine pattern. The levels of the cytokines, tumour necrosis factor-alpha, interleukin 1 beta, interleukin 6, interferon-gamma and interleukin-1 receptor antagonist (IL-1ra) by peripheral blood mononuclear cells (PBMC) were determined simultaneously by the whole-blood assay and the PBMC assay in 20 patients with gastric cancer and in 10 healthy volunteers. In both assays the cytokine levels were lower in patients with cancer compared with healthy controls, with the exception of IL-1ra. In the PBMC assay, the IL-1ra level in cancer patients was significantly higher than that in controls. No statistical correlation between the cytokine levels determined by the two assays was found. We suggest that autologous serum deprivation restored and enhanced IL-1ra production, and normalized the cytokine cascade in immune response, in patients with gastric cancer.