Immunophenotypic changes in NRBCs of Philadelphia chromosome-negative myeloproliferative neoplasms and its clinical significance

Abstract Purpose: Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs) are challenging to differentiate in the early stages. Chronic inflammation and alterations in stromal and immune cells contribute to the MPN pathophysiology. This study evaluated the clinical significance of immunophenotypic alterations in the bone marrow erythrocytes in patients with MPN. Methods: Flow cytometry was used to assess the CD36, CD71, and CD235a expression in bone marrow-nucleated erythrocytes (NRBCs) in patients with polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). Changes in bone marrow-nucleated erythrocyte immunophenotypes in patients with MPN were also analyzed using multiple prognostic scoring systems and clinical parameters. Results: The bone marrow-nucleated erythrocyte expression of CD71 significantly decreased in patients with PMF, and it was positively correlated with the PMF grade. Patients with PV or PMF had a lower NRBC expression of CD36 than those with ET. CD36+NRBC (%) could be a marker for differentiating ET from PMF or PV. The expression of these surface markers was not significantly correlated with gene mutations in patients with MPN. CD71+CD235a-NRBC (%) was positively correlated with prognostic risk factors such as circulating matrices > 1% and white blood cell count > 25 × 109/L in patients with PMF. Moreover, CD235a+NRBC (%) and CD71+CD235a-NRBC (%) were negatively and positively correlated with the clinical and molecular prognostic model score, respectively, in patients with PMF. Conclusion: Patients with PMF who have a higher myelofibrosis grade have a more severely impaired NRBCs. The decreased CD235a expression in the red lineage may be associated with poor prognosis in PMF.