Leucocyte adherence inhibition assay for cell-mediated immunity and immunodiagnosis of pancreatic cancer.

The present study was conducted to determine whether the leucocyte adherence inhibition (LAI) assay was dependent on cell-mediated immunity and whether it was of potential use in diagnosis of pancreatic cancer. The LAI response was significantly positive in 15 PPD skin-test positive individuals but it was abated by pretreatment of sensitized mononuclear cells with anti-T cell antibody (OKT3) or by depletion of monocytes. Therefore, the LAI assay is probably related to cell-mediated immunity. The LAI assay was positive in 13 of 16 patients with pancreatic cancer using pancreatic cancer extract; however, a positive reaction was not found in 11 cases of chronic pancreatitis and 10 cases of hepatocellular carcinoma. Thus, the LAI assay appears rather specific. Mononuclear cells of pancreatic and gastric cancer patients showed LAI reactivity to autologous tumor extracts.