In preclinical experiments, the tumor specificity of MILs, following anti-CD3/CD28 activation, was observed in all patients examined, and one patient in whom a tetramer existed for the HLA-A2+ PR-1 peptide, the precursor frequency of MILs went from 1 to 17.8% following expansion (unpublished data). This evidence concerns the gene CD28 and neoplasm.