NPM1 and acute myeloid leukemia: On the other hand, Forghieri et al., later documented the emergence of NPM1-mutated-specific IFNγ-secreting T cells in 34 of 52 (65.4%) PB samples obtained from 17 adults with NPM1-mutated AML, by ELISPOT assay after 20 hour antigenic stimulation with a comprehensive mixture of 18 (9–18 mers) peptides spanning the C-terminal of NPM1-mutated protein [19].