HLA-A2neg TdTpos malignancies failed to activate T1 and T3 cells, even in the presence of exogenously loaded peptide, while TdTneg HLA-A2pos primary follicular lymphoma and T-ALL cells activated T1 and T3 cells only when loaded with TdT peptides (Extended Data Fig. 7b). Here, DNTT is linked to acute lymphoblastic leukemia.