Evaluation of Cell-Mediated Cytotoxic Reactivity Against Tumor Associated Antigens with 125I-Iododeoxyuridine Labeled Target Cells

Abstract An in vitro lymphocyte cytotoxicity tissue culture assay utilizing 125I-iododeoxy-uridine (125IUdR) labeled target cells is described. Because of the labeling characteristics of 125IUdR this isotope appears to offer advantages over previously used labels. Toxicity of the isotope is a factor to be evaluated with each cell line. The method of calculation of cytotoxicity lends some insight into the spontaneous cell death rate of tissue culture systems as used for cytotoxicity. This assay is of value in detecting tumor-associated antigens in both animal and human tumor systems.