Derived hematological indices during peripheral blood stem cell mobilization in the plerixafor era: insightful dynamics but limited predictive value.

INTRODUCTION

Derived hematological indices reflect immune activation, but their dynamics during the plerixafor era and their predictive value for stem cell yield remain unclear.

OBJECTIVES

To assess changes in derived hematological inflammatory markers during peripheral blood stem cell mobilization in autologous patients and allogeneic donors, and to evaluate their correlation with CD34+ stem cell yield. These markers include ratios (neutrophil-to-lymphocyte, platelet-to-lymphocyte and lymphocyte-to-monocyte), and composite indices (systemic immune-inflammation and systemic inflammation response indices).

METHODS

A retrospective analysis was conducted of 127 autologous and 53 allogeneic mobilization events between January 2019 and March 2024. Blood counts and derived indices were analyzed before and after granulocyte colony-stimulating factor administration with and without plerixafor. CD34+ cell enumeration was performed after mobilization. Dynamic changes in inflammatory indices and their correlation with CD34+ counts were assessed.

RESULTS

After mobilization, there was a significant increase in the neutrophil-to-lymphocyte ratio, systemic immune-inflammation index, and systemic inflammation response index, and a decrease in the platelet-to-lymphocyte and lymphocyte-to-monocyte ratios in both groups. While allogeneic donors had higher CD34+ counts (median 110 cells/µL versus 48 cells/µL in autologous), no consistent correlation was found between dynamic inflammatory marker changes and CD34+ yield. Plerixafor use in autologous patients significantly influenced the platelet-to-lymphocyte ratio and systemic immune-inflammation index dynamics, highlighting its role in modulating the acute inflammatory response in the plerixafor era.

CONCLUSIONS

Inflammatory markers change significantly during mobilization with granulocyte colony-stimulating factor, reflecting acute immune activation. However, the studied markers do not predict CD34+ yield and should not replace direct enumeration. Their role may be better suited to complement biological understanding rather than clinical decision-making.