OBJECTIVETo screen serum biomarkers for minimal residual disease (MRD) monitoring according to differential peptidomics profile in the serum from the patients with acute leukemia (AL) and healthy controls.

METHODSSerum polypeptides from 90 AL patients, 60 healthy controls and 20 patients with benign hematological disorders were enriched by copper chelate magnetic beads, and the peptidomics profile was obtained by matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS) analysis. And the intensities of differential peptides were calculated to assess MRD level.

RESULTSThe diagnostic models by using support vector machine (SVM) algorithm according to differential peptides between AL patients and healthy controls with P<0.01 by t-test were established. The sensitivity and specificity of distinguishing AL patients from healthy controls were 98% and 99%, respectively. The model obtained a sensitivity of 98% and a specificity of 96% for distinguishing newly-diagnosed AL patients from AL patients with hematological complete remission (AL-HCR). Then a sensitivity of 92% and a specificity of 93% were obtained for distinguishing patients with AL-CR from AL patients with molecular complete remission (AL- MR). The intensity of peptide with m/z (mass-to-charge ratio) 4468 was significantly higher in newly- diagnosed AL patients compared to healthy controls, and gradually decreased with the increase of remission degree, and it was not found increase in patients with benign hematological disorders.

CONCLUSIONThe SVM diagnostic model established by differential serum peptide profile could be used to discriminate AL patients with different stages of remission and to evaluate the treatment efficacy. The peptide of m/z 4468 could be used for MRD assessment, and continuous monitoring of its expression level will play an important role in the individual treatment and recurrence prediction.