Automated CD34+ cell isolation of peripheral blood stem cell apheresis product
Gabriele Spohn, Eliza Wiercinska, Darja Karpova, Milica Bunos, Christiane Hümmer, Eva Wingenfeld, Nadine Sorg, Carolin Poppe, Volker Huppert, Juliane Stuth, Kristina Reck, Mike Essl, Erhard Seifried, Halvard Bönig, Gabriele Spohn, Eliza Wiercinska, Darja Karpova, Milica Bunos, Christiane Hümmer, Eva Wingenfeld, Nadine Sorg, Carolin Poppe, Volker Huppert, Juliane Stuth, Kristina Reck, Mike Essl, Erhard Seifried, Halvard Bönig
Abstract
Background aims: Immunomagnetic enrichment of CD34+ hematopoietic "stem" cells (HSCs) using paramagnetic nanobead coupled CD34 antibody and immunomagnetic extraction with the CliniMACS plus system is the standard approach to generating T-cell-depleted stem cell grafts. Their clinical beneficence in selected indications is established. Even though CD34+ selected grafts are typically given in the context of a severely immunosuppressive conditioning with anti-thymocyte globulin or similar, the degree of T-cell depletion appears to affect clinical outcomes and thus in addition to CD34 cell recovery, the degree of T-cell depletion critically describes process quality. An automatic immunomagnetic cell processing system, CliniMACS Prodigy, including a protocol for fully automatic CD34+ cell selection from apheresis products, was recently developed. We performed a formal process validation to support submission of the protocol for CE release, a prerequisite for clinical use of Prodigy CD34+ products.
Methods: Granulocyte-colony stimulating factor-mobilized healthy-donor apheresis products were subjected to CD34+ cell selection using Prodigy with clinical reagents and consumables and advanced beta versions of the CD34 selection software. Target and non-target cells were enumerated using sensitive flow cytometry platforms.
Results: Nine successful clinical-scale CD34+ cell selections were performed. Beyond setup, no operator intervention was required. Prodigy recovered 74 ± 13% of target cells with a viability of 99.9 ± 0.05%. Per 5 × 10E6 CD34+ cells, which we consider a per-kilogram dose of HSCs, products contained 17 ± 3 × 10E3 T cells and 78 ± 22 × 10E3 B cells.
Conclusions: The process for CD34 selection with Prodigy is robust and labor-saving but not time-saving. Compared with clinical CD34+ selected products concurrently generated with the predecessor technology, product properties, importantly including CD34+ cell recovery and T-cell contents, were not significantly different. The automatic system is suitable for routine clinical application.
Keywords: CD34; CliniMACS; Prodigy; allogeneic; automation; cell therapy; clean room; good manufacturing practice; haplo-identical; immunomagnetic; naked haplo; stem cell transplantation.
Copyright © 2015 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.
Source: PubMed