Preparation of cryopreserved chimeric antigen receptor T cells for the locoreogional delivery to the neural axis.

BACKGROUND AIMS: Intracranial (IC) locoregional delivery of chimeric antigen receptor (CAR) T cells presents an attractive delivery method to central nervous system tumors. Although IC delivery is actively being employed in early-phase clinical studies, no thaw/wash methods have been published to remove the neurotoxic cryoprotectant dimethyl sulfoxide (DMSO) from CAR T-cell products before IC administration. Thus, the aim of this study was to develop and validate a simple thaw/wash procedure. METHODS: We developed a thaw/wash procedure that consist of product thaw at 37°C, equilibration for 5 min in 1 volume of preservative-free normal saline (PFNS), dilution with an additional 8 volumes of PFNS, removal of DMSO through a washing step, resuspension in 2.0 mL of PFNS and storage in a syringe at 20-25°C. Final formulated products (FPs) were assessed for quality and safety attributes and stability over 3 h from the completion of the thaw. Stability parameters included CAR T-cell viability, transgene surface expression and cytolytic activity. RESULTS: The developed procedure reduced the calculated % of DMSO to less than 0.025%. FP cell viability and recovery (versus pre-cryopreservation) were within acceptable specifications (mean viability: 85.3%, range: 83%-88%; total nucleated cell recovery mean: 76.5%, range: 65.4%-82.5%). Other prespecified quality assurance/quality control parameters including appearance/ integrity, sterility and endotoxin level (≤1.0 EU/mL), were also met by all FPs (n = 3). Three hours' post thaw/wash stability was confirmed. All products maintained cell viability greater than 70% (mean, 80.0%; range, 79%-81%), with no significant change in transgene expression or cytolytic activity of B7-H3-CAR T cells compared with thawed not diluted/washed control CAR T cells. CONCLUSIONS: We have developed a simple thaw/wash procedure to prepare B7-H3-CAR T cells for their locoregional delivery to the neural axis. While we focus here on CAR T cells, the methods could be readily adapted to other cryopreserved immune effector cell products.

Optimizing haematopoietic stem and progenitor cell apheresis collection from plerixafor-mobilized patients with sickle cell disease.

We adjusted haematopoietic stem and progenitor cell (HSPC) apheresis collection from patients with sickle cell disease (SCD) by targeting deep buffy coat collection using medium or low collection preference (CP), and by increasing anticoagulant-citrate-dextrose-solution A dosage. In 43 HSPC collections from plerixafor-mobilized adult patients with SCD, we increased the collection efficiency to 35.79% using medium CP and 82.23% using low CP. Deep buffy coat collection increased red blood cell contamination of the HSPC product, the product haematocrit was 4.7% with medium CP and 6.4% with low CP. These adjustments were well-tolerated and allowed efficient HSPC collection from SCD patients.

Standardization of cellular therapy terminology, coding and labeling: a review.

The 1990s saw rapid growth in international activity in hematopoietic cell transplantation. As national donor registries were established and international collaboration increased, a need to transfer cellular therapy products across national borders emerged. A lack of international standards for identification, terminology and labeling resulted in significant challenges for import and export. Twenty years of effort by a large group of experts supported by professional societies and accreditation bodies has today achieved a high degree of standardization. This review highlights the main landmarks in this journey and serves as a reminder of the importance of taking the "long view" when working toward international standardization. It demonstrates the need for continual maintenance and enhancement of standards to meet the changing needs of the cell therapy industry and highlights recent developments in ISBT 128.

ISBT 128 implementation plan for cellular therapy products.

The publication of new standards for terminology and labeling marks an important step in ensuring consistency and traceability of cellular therapies at the global level. However, it is only with the widespread implementation of the standard that the benefits can be truly realized. This paper provides guidance on the practical aspects of adopting these new standards for organizations with differing current levels of computerization. It discusses project management, equipment, licensing, and validation topics.

CD34(+) hematopoietic progenitor cell selection of bone marrow grafts for autologous transplantation in pediatric patients.

CD34(+)-selection of hematopoietic grafts for patients undergoing autologous hematopoietic stem cell transplantation (HSCT) is frequently used to obtain a tumor-free graft. The majority of published experience is with peripheral blood stem cell (PBSC) products; only scant information has been published on bone marrow (BM) grafts. We reviewed our experience using CD34(+) selection of BM grafts in children undergoing autologous BM transplantation. After obtaining institutional approval, we performed a retrospective review of the medical records of patients who underwent autologous stem cell collection at St. Jude. From January 1, 1999, to December 31, 2003, 373 patients underwent autologous HSCT; 131 received marrow grafts, 237 received PBSC grafts, and 5 received a combination. Seventeen patients underwent BM harvests for CD34(+) selection of their stem cell grafts. Sixteen patients received 19 CD34 purified grafts processed on the Isolex 300i Magnetic Cell Selection System device. Four patients were not included in the engraftment analysis as 1 did not receive the collected product, 1 received a tandem product, and 2 received products that were composed of 2 or 3 combined purified products. Following selection, marrow grafts contained a median of 1.4 x 10(6) CD34(+) cells/kg (range: 0.09-8.3 x 10(6)/kg) and a median of 0.014 x10(8) total nucleated cell cells/kg (range: 0.001-0.09 x 10(8)/kg). The median CD34% recovery was 30.9% (range: 9.3%-57.1%), with the median CD34 purity being 95.5% (range: 62.2%-98.8%). All patients engrafted. The median time to absolute neutrophil count > or = 500/mm(3) was 19 days (range: 12-35 days), and to platelet recovery was 28 days (range 18-37 days). No patient died from transplant-related complications. Our study demonstrates that CD34(+)-selection of marrow grafts is feasible, and these grafts are able to successfully reconstitute hematopoiesis in patients undergoing autologous BMT.