As tumour cells cultured in 3D are unfit to serve as targets for 51Cr release assays, because washing steps required after labelling disrupt cell aggregates, we turned to IFN-γ production by antigen-specific T cells following interaction with targets expressing appropriate TAA and restriction determinants, as a classical alternative antigen recognition assay (Butterfield et al, 1999; Pelfrey et al, 2000). This evidence concerns the gene IFNG and neoplasm.