Immunomodulation Induced by Stem Cell Mobilization and Harvesting in Healthy Donors: Increased Systemic Osteopontin Levels after Treatment with Granulocyte Colony-Stimulating Factor

Increased Serum Levels of N-terminal pro-B-type Natriuretic Peptide (NT-proBNP) in Mobilized Healthy Donors with G-CSF: A Cohort Study

Limited data regarding elevation of N-terminal pro-B-type natriuretic peptide (NT-proBNP) in mobilized donors with G-CSF is available. We extended these findings by examining serum NT-proBNP in a cohort study including 35 healthy donors and 69 patients who received G-CSF for CD34+ mobilization as well as 54 patients who did not receive G-CSF but who underwent collection of CD3+ cells for chimeric antigen receptor (CAR) T-cell manufacturing. No donor in the three cohorts experienced significant cardiac adverse events. NT-proBNP levels were measured before and after G-CSF administration and after finishing apheresis procedure. NT-proBNP increase was observed in mobilized healthy donors after G-CSF administration, but was not observed in mobilized or non-mobilized patients. Only in the cohort of healthy donors, pairwise comparisons using Wilcoxon signed ranks test showed a significant increase between the mean serum NT-proBNP level after G-CSF administration and the mean serum NT-proBNP level measured before G-CSF administration (231.09 ± 156.15 pg/mL vs. 58.88 ± 26.84 pg/mL; P < .01). No correlation was observed between NT-proBNP increase and G-CSF dose (rs = 0.09; n = 32; P = .6) and no other variables contributing to predict serum NT-proBNP increase were detected. In conclusion, we observed a statistically, although not clinically, significant increase of NT-proBNP in healthy donors who received G-CSF as CD34+ cell mobilization.

Increased serum pro-B-type natriuretic peptide in hematopoietic progenitor cell donors stimulated with G-CSF

Hematopoietic stem cells (HPCs) donors mobilized by granulocyte-colony-stimulating factor (G-CSF) can develop various signs and symptoms. proBNP (pro-B-type natriuretic peptide) is a serum marker of heart failure. A donor who developed severe adverse reactions after G-CSF mobilization was found to have high serum proBNP levels. We followed additional donors who received identical mobilization regimen to investigate the prevalence of this phenomenon. Eighteen healthy donors underwent a mobilization regimen of 10 μg/Kg G-CSF daily for 5 days prior to allogeneic HPC collection using Spectra Optia between January 2016 and February 2017 were included in this study. Serum proBNP levels were measured before and after G-CSF stimulation and immediately after apheresis. Apheresis collection parameters and other laboratory results were also reviewed. The majority of donors (86.7%) had post-G-CSF elevation of serum proBNP. Seven of those had elevated proBNP above upper normal range (124 pg/ml). The subgroup of donors with normal proBNP is younger (median age of 37 vs 42 years), with majority being male (90.9% vs 28.6%) and with smaller processed blood volume (2.2 vs 3 × total blood volume). This case series demonstrates an increase of serum proBNP can be common in HPC donors stimulated with 5 days of 10 mcg/kg G-CSF. This is an adverse reaction that has not been described before. The temporary elevation of proBNP in these donors is not associated with ventricular dysfunction of the heart. The risk factors for marked elevation of proBNP post-G-CSF should be further investigated.