Abstract
<jats:p>Background aims: The development of next generation therapies for sickle cell disease (SCD) and beta thalassemia (beta thal), including fetal globin inducing small molecules and gene therapy approaches, depends on patient derived CD34+ hematopoietic stem and progenitor cells (HSPCs) for discovery and preclinical validation, but commercial vendors stock only healthy donor material and disease specific banks hold limited inventories. Recent US Food and Drug Administration and National Institutes of Health guidance favoring human cell based methods over animal testing underscores the value of authentic patient cells. Methods: Over 14 months we recovered, purified, and biobanked CD34+ HSPCs from clinical apheresis product waste and mobilized peripheral blood (PB) otherwise discarded after clinical procedures, using immunomagnetic selection adapted for hemoglobinopathy specimens; a microfluidic technology was evaluated separately. We quantified yield and purity for bead selected material and cell number and viability for the microfluidic pilot; engraftment was tested in NBSGW mice. Results: Immunomagnetic selection recovered a median of 4.71 x 106 CD34+ cells from just 1 to 2 mL of apheresis product waste, comparable to the 6.0 x 106 cells from a 10 to 40 fold larger volume of PB waste, with similar purity across sources and diagnoses. Because apheresis product waste is far more concentrated, it reaches equivalent yields without the density gradient steps required for PB waste, approximately halving processing time. Recovered cells engrafted NBSGW mice, confirming preserved repopulating capacity. The microfluidic pilot (two patients, 11 specimens) recovered 2.17 x 106 CD34+ cells per specimen at greater than 90% viability and purity. Conclusions: A center with existing apheresis infrastructure can reproducibly recover, bank, and distribute research rade patient CD34+ HSPCs, addressing a recognized gap in the hemoglobinopathy pipeline.</jats:p>