Enzyme-linked immunosorbent assays (ELISA) for the detection of antibodies to UK114 and UK150

Doses of UK101, a mammalian liver-extracted protein consisting of UK110, UK114 and UK150, were administered to advanced neoplastic patients to try a specific immunotherapy: Two ELISA immunoassays were developed in order to evaluate the antiUK114 and antiUK150 antibody titre. In both methods, we used the specific protein (UK114 or UK150) bound onto polystyrene microwells as catcher and a purified anti-human IgG (Fc) conjugated with horseradish peroxidase as tracer. The enzymatic activity bound onto solid phase was detected by TMB/H2O2 chromogen /substrate system. A calibration curve was constructed by using a pool of UK101-treated patients' sera, which showed high concentrations of antiUK114 or antiUK150 antibodies. The antibody activity of each pool was expressed in arbitrary unit (U/mL) and a panel of 86 normal human sera drawn from hospital blood bank was used to define the cut-off values of the assays. The evaluation of the antiUK114 antibody titre in 30 breast cancer patients and 31 colon cancer patients submitted to UK101 therapy is here reported. An increase of 63% and 87% was detected after 40 days of UK101 administration in the two groups of terminally ill patients, respectively.