Allogeneic donor peripheral blood “stem cell” apheresis: prospective comparison of two apheresis systems

Apheresis collection of mononuclear cells for chimeric-antigen receptor therapies

Collections of lymphocytes to be genetically modified to treat hematologic malignancies have seen a dramatic increase over the last few years as commercial products have been approved. Reports of new products in development that can possibly treat solid organ malignancies represent a massive change in the field. Apheresis is at the center of the collection of cells for the manufacture of these chimeric-antigen receptor therapy products. The expansion of these collections represents one of the areas of apheresis procedures growth. This review will summarize concepts important to this type of collection and variables that need to be optimized to obtain desired cell yields while increasing patients' safety.

Evaluating the efficiency and safety of large-volume leukapheresis using the Spectra Optia continuous mononuclear cell collection protocol for peripheral blood stem cell collection from healthy donors: A retrospective study

BACKGROUND

Large-volume leukapheresis (LVL) refers to processing of more than three volumes of blood in a single session for peripheral blood stem cell collection. Recently, continuous mononuclear cell collection (cMNC) protocol has been developed using the Spectra Optia system, which is a widely used apheresis device. LVL using the novel protocol has been investigated in patients. However, the efficiency and safety of LVL in healthy donors using this protocol has not been characterized. Therefore, this study aimed to evaluate the efficiency and tolerability of CD34+ collection of LVL with the cMNC protocol in healthy donors.

STUDY DESIGN AND METHODS

We retrospectively collected data on LVL (>3 total blood volume) and normal-volume leukapheresis (NVL) performed in healthy donors between October 2019 and December 2021. All procedures were performed using the cMNC protocol.

RESULTS

Although pre-apheresis CD34+ cell count was lesser in LVL (23.5 vs. 58.0/μL, p < .001), CD34+ collection efficiency was comparable between LVL and NVL (61.2% vs. 61.4%, p = .966). Platelet loss was significantly higher in LVL compared to NVL (38.0% vs. 29.4%, p < .001), with no correlation between attrition of platelet and processing blood volume. Moreover, the incidence of citrate toxicity during procedures was comparable between the two groups (31.6% vs. 21.4%, p = .322). All LVL procedures could be completed without any adverse events.

CONCLUSION

Allogeneic LVL procedure using Spectra Optia cMNC protocol was well tolerated by the donors and resulted in efficient collection of CD34+ cells, which was comparable to that of NVL.

Impact of Mobilization Strategies on Peripheral Blood Stem Cell Collection Efficiency and Product Quality: A Retrospective Single-Center Study

Autologous stem cell transplantation is routinely used in the management of several hematological diseases, solid tumors, and immune disorders. Peripheral blood stem cell (PBSC) collection performed by apheresis is the preferred source of stem cells. In this study, the potential impact of mobilization regimens on the performance of the Spectra Optia^® continuous mononuclear cell collection system was evaluated. We performed a retrospective data analysis for patients undergoing autologous PBSC collection at the Medical University Vienna, Vienna General Hospital between September 2016 and June 2018. Collections were divided into two main groups according to the mobilization regimen received: without (210 collections) or with (99 collections) plerixafor. Assessed variables included product characteristics and collection efficiency (CE). Overall, product characteristics were similar between the groups. Median CD34+ CE2 was 50.1% versus 53.0%, and CE1 was 66.9% versus 69.9% following mobilization without and with plerixafor, respectively; the difference was not statistically significant. Simple linear regression showed a very weak positive correlation between the mobilization method and CE1 or CE2 (mobilization with plerixafor increased CE2 by 4.106%). In conclusion, the Spectra Optia^® apheresis system led to high CE and a good quality of PBSC products when mobilization regimens with or without plerixafor were used.

A clinically applicable prediction model to improve T-cell collection in CAR-T cell therapy

As chimeric antigen receptor T (CAR-T) cell therapy targeting CD19 has shown favorable outcomes in patients with relapsed or refractory (r/r) mature B-cell lymphomas and B-cell acute lymphoblastic leukemia (B-ALL), the number of patients who are waiting to receive these treatments is increasing. Optimized protocols for T-cell collection by lymphapheresis for chimeric antigen receptor (CAR) -T cell therapy must be urgently established to provide CAR-T cell therapy for patients with refractory and progressive disease, and/or a low number of lymphocytes due to prior chemotherapies. Predicted collection efficiency of CD3⁺ cells in apheresis can guide protocols for apheresis, but a clinically applicable model to produce reliable estimates has not been established yet. Therefore, we prospectively analyzed lymphapheresis procedures for tisagenlecleucel therapy at two centers. A total of 108 apheresis procedures included 20 procedures for patients with B-cell acute lymphoblastic leukemia, and 88 for patients with diffuse large B-cell lymphoma, with a median age at apheresis of 58 years (1-71). After lymphapheresis with a median processing blood volume of 10 L (3-16), a median of 3.2 × 10⁹ (0.1-15.0) CD3⁺ cells were harvested. Collection efficiency 2 (CE2) for CD3⁺ cells was highly variable (median, 59.3%; range 11.0-199.8). Multivariate analyses revealed that lower Hgb levels, higher circulating CD3⁺ cell counts, and higher platelet counts before apheresis significantly decreased apheresis CE2. Based on multivariate analyses, we developed a novel formula that estimates CE2 from pre-collection parameters with high accuracy (r = 0.56, p < 0.01), which also suggests the necessary processing blood volume. Our strategy in lymphapheresis should be helpful to reduce collection failure, as well as to achieve efficient utilization of medical resources in clinical practice, thereby delivering CAR-T cell therapy to more patients in a timely manner.

Retrospective comparison between COBE SPECTRA and SPECTRA OPTIA apheresis systems for hematopoietic progenitor cells collection for autologous and allogeneic transplantation in a single center

INTRODUCTION

COBE SPECTRA [COBE] (Terumo, BCT Lakewood CO) apheresis system has been the most used device for hematopoietic progenitor cells (HPC) collection. Recently, it has been replaced by the SPECTRA OPTIA [OPTIA] (Terumo, BCT Lakewood CO) apheresis system. The aim of our study is to compare both methods for HPC collection.

MATERIAL AND METHODS

We retrospectively compared 302 HPC collection apheresis procedures (115 allogeneic donors and 187 autologous). The study cohort was divided according to the apheresis system used to analyze the differences between COBE and OPTIA, specifically efficacy of apheresis procedure and product characteristics.

RESULTS

OPTIA collections result in a higher CD34⁺ collection efficiency in both groups (autologous 45.3% vs 41%, P < .006; allogeneic 54.9% vs 45%, P < .0001). The total of CD34⁺ cells ×10⁶ /kg recipient collected in the product were comparable in both groups (autologous 2.9 in OPTIA group vs 2.8 in COBE group, P = .344; allogeneic 6.2 in OPTIA group vs 5.8 in COBE group, P = .186). The percentage of platelet loss in autologous donors was significantly lower (35.7% vs 40.8%, P < .01). Regarding quality of the product, we observed a significantly lower hematocrit in products collected with OPTIA in both groups (1.8% vs 4%, P < .0001) as well as significantly lower amount of leukocytes (median 153.4 vs 237.2 × 10⁹ /L in autologous, P < .0001; 239.5 vs 340.2 × 10⁹ /L in allogeneic P < .0001).

CONCLUSION

Both apheresis systems are comparable in collection of hematopoietic progenitor cells, with significantly higher collection efficiency with the OPTIA system. Collection products obtained with OPTIA contain significantly lower hematocrit and leukocytes.

Unstimulated apheresis for chimeric antigen receptor manufacturing in pediatric/adolescent acute lymphoblastic leukemia patients

Autologous unstimulated leukapheresis product serves as starting material for a variety of innovative cell therapy products, including chimeric antigen receptor (CAR)-modified T-cells. Although it may be reasonable to assume feasibility and efficiency of apheresis for CAR-T cell manufacture, several idiosyncrasies of these patients warrant their separate analysis: target cells (mononuclear cells [MNC] and T-cells) are relatively few which may instruct the selection of apheresis technology, low body weight, and, hence, low total blood volume (TBV) can restrict process and product volume, and patients may be in compromised health. We here report outcome data from 46 consecutive leukaphereses in 33 unique pediatric patients performed for the purpose of CD19-CAR-T-cell manufacturing. Apheresis targets of 2×10⁹ MNC/1×10⁹ T-cells were defined by marketing authorization holder specification. Patient weight was 8 to 84 kg; TBV was 0.6 to 5.1 L. Spectra Optia apheresis technology was used. For 23 patients, a single apheresis sufficed to generate enough cells and manufacture CAR-T-cells, the remainder required two aphereses to meet target dose and/or two apheresis series because of production failure. Aphereses were technically feasible and clinically tolerable without serious adverse effects. The median collection efficiencies for MNC and T-cells were 53% and 56%, respectively. In summary, CAR apheresis in pediatric patients, including the very young, is feasible, safe and efficient, but the specified cell dose targets can be challenging in smaller children. Continuous monitoring of apheresis outcomes is advocated in order to maintain quality.

Mobilization and collection of cells in the hematologic compartment for cellular therapies: Stem cell collection with G-CSF/plerixafor, collecting lymphocytes/monocytes

An essential and influential first step in all cellular therapies is collecting donor or patient cells. In hematopoietic progenitor cell transplantation, autologous or allogeneic hematopoietic progenitor cells (HPCs) are collected from either the bone marrow or the peripheral blood. Peripheral blood collection by apheresis requires mobilization with chemotherapy, granulocyte colony stimulating factor (G-CSF), plerixafor, or a combination. The modalities of mobilization and collection each carry a unique set of risks and benefits for both the donor and the recipient. In other types of cell therapy, most notably chimeric antigen receptor T cells, lymphocytes or monocytes are collected from the peripheral blood. The risks of collecting these cells by apheresis are similar to HPCs, but less is known about the composition, timing and qualitative cell characteristics which contribute to an optimal collection. Here, we review the mobilization and collection of HPCs and the collection of lymphocytes and monocytes. Donor safety is of primary importance when collecting material for any type of cell therapy. Every aspect of mobilization and collection can be studied and potentially optimized to improve patient outcomes.

Mobilized peripheral blood stem cell apheresis via Hickman catheter in pediatric patients

BACKGROUND

Autologous stem cell transplantation remains an integral treatment tool for certain childhood malignancies. In children, a central venous catheter is typically necessary to provide adequate flow rates for preparative apheresis. In this study, the feasibility and efficiency of collecting CD34+ cells via an indwelling Hickman catheter, preimplanted for chemotherapy, instead of placing an additional temporary central venous catheter was evaluated.

STUDY DESIGN AND METHODS

Forty-eight pediatric leukaphereses for autologous hematopoietic stem cell transplantation using Spectra Optia MNC, Version 3.0 were reviewed. We compared preimplanted Hickman catheters with a temporary Shaldon catheter, inserted for apheresis. Apheresis was considered successful if a dose of 2 × 10⁶ CD34+ peripheral blood stem cells/kg BW was achieved.

RESULTS

In 43 (89.6%) of the 48 patients, a Hickman catheter was used for leukapheresis. Only 5 patients (10.4%) received a temporary Shaldon catheter. In both groups, apheresis was performed without apparent adverse reactions. The dose of collected CD34+ peripheral blood stem cells was 12.7 × 10⁶ (range, 2.3-70.7 × 10⁶ ) cells/kg BW in the Hickman group and 16.2 × 10⁶ (range, 3.8-48.4 × 10⁶ ) cells/kg BW in the Shaldon group, showing no statistically significant difference (p = 0.58). In both groups, the primary endpoint of a minimal CD34+ cell concentration of 2 × 10⁶ cells/kg BW was achieved at a maximum of two leukapheresis sessions. Apheresis efficacy was further confirmed by the collection efficiency of 40.2% in the Hickman group and 27.8% in the Shaldon group (p = 0.32).

CONCLUSION

These data indicate the reliable feasibility and efficacy of mobilized apheresis via an indwelling Hickman catheter. In light of this, the routine insertion of a dialysis catheter for the purpose of leukapheresis should be critically reconsidered.

Mobilization and Collection of Peripheral Blood Stem Cells in Adults: Focus on Timing and Benchmarking

Peripheral blood stem cells (PBSCs) are preferentially used as a hematopoietic stem cell source for autologous blood stem cell transplantation (ABSCT) upon high-dose chemotherapy (HDT) in a variety of hemato-oncologic diseases. As a prerequisite, hematopoietic stem cells have to be mobilized into the peripheral blood (PB) and collected by leukapheresis (LP). Despite continuous improvements, e.g., the introduction of plerixafor, current challenges are the further optimization regarding the leukapheresis procedure, preventing collection failures, as well as benchmarking and harmonization of mobilization approaches between institutions.This chapter summarizes the current PBSC mobilization and collection approaches and is focusing on timely orchestration of mobilization therapy, granulocyte colony-stimulating factor (G-CSF) application, and peripheral blood (PB) CD34⁺ cell assessment. Moreover, strategies for prediction and performance assessment of the PBSC collection yield are discussed.

Impact of good and poor mobilizers on hematopoietic progenitor cell collection efficiency and product quality

BACKGROUND

Mobilization regimen choice is a significant contributing factor for successful hematopoietic progenitor cell (HPC) collection by leukocytapheresis and reaching the target CD34+ cell dose. How mobilization regimen affects collection efficiency and the quality of products collected using the Spectra Optia apheresis instrument is not fully known.

METHODS

We evaluated the impact of granulocyte-colony stimulating factor (GCSF) and GCSF/plerixafor mobilization regimens on CE and product composition. We studied 373 leukocytapheresis HPC collections for 147 autologous transplants from January 1, 2010 to December 31, 2014. Patients were categorized in two groups; good mobilizers, mobilized with GCSF only (GM) and poor mobilizers, mobilized with GCSF and Plerixafor (PM).

RESULTS

Overall, compared with PM group, total nucleated cell (TNC) yield was significantly lower in GM group (P = <.001). In contrast, median percent mononuclear cell (MNC) collected from GM (86.5%) was significantly higher than products collected from PM group (79.5%; P < .001). Compared with GM group, CD34+ cell CE was about 10% lower in PM group (P < .008). In addition, daily CD34+ cell/Kg yield was significantly higher in GM (2.08 × 10/Kg) compared with PM group (1.64 x 10/Kg, P = .019). Overall, the median number of collections per patient was two for GM and three for PM (P = .004).

CONCLUSION

Products collected from PM group contained higher TNC content relative to GM group but had lower MNC enrichment, CD34+ cell CE and daily CD34+ cell yield per Kg.

A Comparison of Fresenius Com.Tec Cell and Spectra Optia Cell Separators for Autologous and Allogeneic Stem Cell Collections: Single Center Experience

Peripheral blood is the prefered source for hematopoietic stem cells for hematopoietic stem cell transplantation. The efficiency of peripheral blood stem cell (PBSC) collection can vary among devices. In this study we aimed to compare feasibility and effectivity of apheresis procedures of the different systems. Two apheresis systems [Com.Tec (Fresenius Healthcare) and Spectra Optia (Caridian BCT)] were used in our center for the collection of PBSCs for autologous and allogeneic transplantation. We retrospectively analysed 190 apheresis procedures performed in healthy donors and patients between June 2012 and November 2014 in Department of Hematology, Dokuz Eylul University. PBSCS were collected by Fresenius cell separator (64 procedure) or Spectra Optia cell separator (126 procedure). Mobilization treatments were G-CSF (26.8%), cyclophosphamide plus G-CSF (48.4%), prelixafor plus G-CSF (14.7%), ESHAP (10%) and others. Patient and donor characteristics (age, weight, volume processed, disease, mobilization regimes) were similar in Fresenius and Spectra Optia apheresis groups. Altough both collected PBSCs efficiently, the amount of CD34+ cell in product collected by Spectra Optia device was significantly higher (p < 0.05) and product volume was lower than Fresenius Com.Tec significantly (p < 0.05). "CD34+ collection efficiency" with Spectra Optia was significantly higher than Fresenius Com.Tec (CE2: 87%, 70%, p = 0.033) regarding all procedures. High collection efficiency and low product volume may be a significant characteristic of Spectra Optia device (mean 187 mL, product CD34+ cell: 1576 µL).

The healthy donor profile of immunoregulatory soluble mediators is altered by stem cell mobilization and apheresis

BACKGROUND

Peripheral blood stem cells from healthy donors mobilized by granulocyte colony-stimulating factor (G-CSF) and thereafter harvested by leukapheresis are commonly used for allogeneic stem cell transplantation.

METHODS

Plasma levels of 38 soluble mediators (cytokines, soluble adhesion molecules, proteases, protease inhibitors) were analyzed in samples derived from healthy stem cell donors before G-CSF treatment and after 4 days, both immediately before and after leukapheresis.

RESULTS

Donors could be classified into two main subsets based on their plasma mediator profile before G-CSF treatment. Seventeen of 36 detectable mediators were significantly altered by G-CSF; generally an increase in mediator levels was seen, including pro-inflammatory cytokines, soluble adhesion molecules and proteases. Several leukocyte- and platelet-released mediators were increased during apheresis. Both plasma and graft mediator profiles were thus altered and showed correlations to graft concentrations of leukocytes and platelets; these concentrations were influenced by the apheresis device used. Finally, the mediator profile of the allotransplant recipients was altered by graft infusion, and based on their day +1 post-transplantation plasma profile our recipients could be divided into two major subsets that differed in overall survival.

DISCUSSION

G-CSF alters the short-term plasma mediator profile of healthy stem cell donors. These effects together with the leukocyte and platelet levels in the graft determine the mediator profile of the stem cell grafts. Graft infusion also alters the systemic mediator profile of the recipients, but further studies are required to clarify whether such graft-induced alterations have a prognostic impact.

Change of apheresis device decreased the incidence of severe acute graft-versus-host disease among patients after allogeneic stem cell transplantation with sibling donors

BACKGROUND

The composition of the graft used for allogeneic hematopoietic stem cell transplantation (HSCT) is important for the treatment outcome. Different apheresis devices may yield significant differences in peripheral blood stem cell graft cellular composition. We compared stem cell grafts produced by Cobe Spectra (Cobe) and Spectra Optia (Optia) with use of the mononuclear cell (MNC) protocol, and evaluated clinical outcome parameters such as graft-versus-host disease (GvHD), transplant-related mortality (TRM), relapse, and overall survival.

STUDY DESIGN AND METHODS

During 5 years, 31 Cobe Spectra and 40 Spectra Optia grafts were analyzed for CD34, CD3, CD4, CD8, CD19, and CD56 cell content. Clinical outcome parameters were correlated and compared between the two patient groups using different apheresis devices.

RESULTS

Optia grafts contained fewer lymphocytes compared to Cobe (p < 0.001). Optia grafts had a significantly lower incidence of acute GvHD Grades II through IV (Cobe 45% vs. Optia 23%; p = 0.039) and TRM (16% vs. 2.5%; p < 0.05) but higher chronic GvHD (32% vs. 67%; p = 0.005) compared to Cobe grafts. Finally, the multivariate analysis showed a significant correlation among the different apheresis devices and both acute GvHD II through IV and severe chronic GvHD. The multivariate analysis also showed a significant correlation between the CD3+ cell dose and the incidence of severe acute GvHD.

CONCLUSION

Optia-obtained grafts yielded a lower acute GvHD Grades II-IV and TRM risk, but had no impact on relapse or overall survival in this study. Understanding and further improvement of peripheral blood stem cell (PBSC) apheresis techniques may be used in the future to personalize HSCT by, for example, fine-tuning the GvHD incidence.

Comparison of Two Apheresis Systems of COBE and Optia for Autologous Peripheral Blood Stem Cell Collection

Peripheral blood stem cell (PBSC) transplantation following myeloablative therapy is a mainstay of treatment for various types of malignancies. This study aimed to evaluate the differences between the Optia MNC and COBE Spectra MNC systems (Terumo BCT, Japan) according to apheresis procedures and the parameters of apheresis, products, and collection. The clinical data of 74 patients who underwent autologous PBSC collection from July 2012 to July 2015 were reviewed retrospectively. The patients comprised 48 (65%) men and 26 (35%) women with a median age of 56 yr (range, 23–66 yr). Of 216 procedures, 111 (51%) and 105 (49%) were processed by using COBE and Optia MNC, respectively. PBSC collection rates, throughput, numbers of stem cells retrieved, collection efficacy, and platelet loss were compared. There were no significant differences in the median CD34+ cell counts of collected products (0.61×10⁸ vs 0.94×10⁸), CD34 collection efficiency (43.5% vs 42.1%), and loss of platelets (40.1% vs 44.7%). The Spectra Optia MNC apheresis system was comparable to the COBE Spectra system in collecting autologous CD34+ hematopoietic stem cells and retention of platelets.

Activation of Notch1 signaling alleviates dysfunction of bone marrow-derived mesenchymal stem cells induced by cigarette smoke extract

Bone marrow-derived mesenchymal stem cells (BM-MSCs) are considered attractive therapeutic agents for the treatment of COPD. However, little is known about the impact of Notch on the proliferation, migration, and survival of MSCs in a cigarette smoke (CS) microenvironment. Here, we used CS extract to mimic the CS microenvironment in vitro, with the intention to investigate the effect of Notch in regulating proliferation, migration, and survival of BM-MSCs. Rat bone marrow mesenchymal stem cells were infected with lentivirus vector containing the intracellular domain of Notch1 (N1ICD) and challenged with CS extract. Cell proliferation was detected by Ki67 staining and expression of cell cycle-related proteins. A transwell assay was used to measure cell migration and the expression of apoptotic proteins was examined. The proliferation of BM-MSCs overexpressing N1ICD significantly increased. Consistently, levels of cyclin D1, p-Rb, and E2F-1 increased in N1ICD overexpressing cells. N1ICD overexpression also increased cell migration compared with the control group. N1ICD overexpression equilibrated the expression of Bax and Bcl-2, and blocked caspase-3 cleavage, contributing to the inhibition of apoptosis. Moreover, blockade of the PI3K/Akt pathway suppressed the aforementioned cytoprotective effects of N1ICD. In conclusion, activation of Notch signaling improved proliferation, migration, and survival of BM-MSCs in a CS microenvironment partly through the PI3K/Akt pathway.

A roadmap for cost-of-goods planning to guide economic production of cell therapy products

Cell therapy products are frequently developed and produced without incorporating cost considerations into process development, contributing to prohibitively costly products. Herein we contextualize individual process development decisions within a broad framework for cost-efficient therapeutic manufacturing. This roadmap guides the analysis of cost of goods (COG) arising from tissue procurement, material acquisition, facility operation, production, and storage. We present the specific COG considerations related to each of these elements as identified through a 2013 International Society for Cellular Therapy COG survey, highlighting the differences between autologous and allogeneic products. Planning and accounting for COG at each step in the production process could reduce costs, allowing for more affordable market pricing to improve the long-term viability of the cell therapy product and facilitate broader patient access to novel and transformative cell therapies.

Erythrocyte depletion from bone marrow: performance evaluation after 50 clinical-scale depletions with Spectra Optia BMC

BACKGROUND

Red blood cell (RBC) depletion is a standard graft manipulation technique for ABO-incompatible bone marrow (BM) transplants. The BM processing module for Spectra Optia, "BMC", was previously introduced. We here report the largest series to date of routine quality data after performing 50 clinical-scale RBC-depletions.

METHODS

Fifty successive RBC-depletions from autologous (n = 5) and allogeneic (n = 45) BM transplants were performed with the Spectra Optia BMC apheresis suite. Product quality was assessed before and after processing for volume, RBC and leukocyte content; RBC-depletion and stem cell (CD34+ cells) recovery was calculated there from. Clinical engraftment data were collected from 26/45 allogeneic recipients.

RESULTS

Median RBC removal was 98.2% (range 90.8-99.1%), median CD34+ cell recovery was 93.6%, minimum recovery being 72%, total product volume was reduced to 7.5% (range 4.7-23.0%). Products engrafted with expected probability and kinetics. Performance indicators were stable over time.

DISCUSSION

Spectra Optia BMC is a robust and efficient technology for RBC-depletion and volume reduction of BM, providing near-complete RBC removal and excellent CD34+ cell recovery.

Donor Safety in Haemapheresis: Development of an Internet-Based Registry for Comprehensive Assessment of Adverse Events from Healthy Donors

BACKGROUND

Currently, there is an extensive but highly inconsistent body of literature regarding donor adverse events (AEs) in haemapheresis. As the reports diverge with respect to types and grading of AEs, apheresis procedures and machines, the range of haemapheresis-related AEs varies widely from about 0.03% to 6.6%.

METHODS

The German Society for Transfusion Medicine and Immunohaematology (DGTI) formed a 'Haemapheresis Vigilance Working Party' (Arbeitsgemeinschaft Hämapheresevigilanz; AGHV) to create an on-line registry for comprehensive and comparable AE assessment with all available apheresis devices in all types of preparative haemapheresis: plasmapheresis (PLS), plateletpheresis (PLT), red blood cell apheresis, all kind of leukaphereses (autologous/allogeneic blood stem cell apheresis, granulocyte apheresis, lymphocyte/monocyte apheresis) and all possible types of multi-component apheresis. To ensure the comparability of the data, the AGHV adopted the 'Standard for Surveillance of Complications Related to Blood Donation' from the International Society for Blood Transfusion in cooperation with the International Haemovigilance Network (IHN) and the American Association of Blood Banks for AE acquisition and automated evaluation. The registry is embedded in a prospective observational multi-centre study with a study period of 7 years.

RESULTS

A preliminary evaluation encompassed the time period from January, 2012 to December, 2015. During this time, the system proved to be safe and stable. Out of approximately 345,000 haemaphereses 16,477 AEs were reported (4.9%) from 20 participating centres. The majority of AEs occurred in PLSs (63%), followed by PLT (34.5%) and SC (2.2%). Blood access injuries (BAI) accounted for about 55% of the supplied AEs, whereas citrate toxicity symptoms, vasovagal reactions and technical events (e.g. disposable leakages, software failures) rather equally affected haemaphereses at 8-15%. Out of 12,348 finalized AEs, 8,759 (70.1%) were associated with a procedure-related break-off, with BAI being the prevailing cause (5,463/8,759; 62.4%). An automated centre- and procedure-specific AE evaluation according to the latest IHN standard and AGHV pre-settings is available within a few minutes.

CONCLUSIONS

An on-line electronic platform for comprehensive assessment and centre-specific automated evaluation of AEs in haemaphereses has been developed and proved to be stable and safe over a period of 4 years.

Autologous Stem Cell Mobilization and Collection

Peripheral blood stem cell collection is an effective approach to obtain a hematopoietic graft for stem cell transplantation. Developing hematopoietic stem/progenitor cell (HSPC) mobilization methods and collection algorithms have improved efficiency, clinical outcomes, and cost effectiveness. Differences in mobilization mechanisms may change the HSPC content harvested and result in different engraftment kinetics and complications. Patient-specific factors can affect mobilization. Incorporating these factors in collection algorithms and improving assays for evaluating mobilization further extend the ability to obtain sufficient HSPCs for hematopoietic repopulation. Technological advance and innovations in leukapheresis have improved collection efficiency and reduced adverse effects.

Genetic Engineering and Manufacturing of Hematopoietic Stem Cells

The marketing approval of genetically engineered hematopoietic stem cells (HSCs) as the first-line therapy for the treatment of severe combined immunodeficiency due to adenosine deaminase deficiency (ADA-SCID) is a tribute to the substantial progress that has been made regarding HSC engineering in the past decade. Reproducible manufacturing of high-quality, clinical-grade, genetically engineered HSCs is the foundation for broadening the application of this technology. Herein, the current state-of-the-art manufacturing platforms to genetically engineer HSCs as well as the challenges pertaining to production standardization and product characterization are addressed in the context of primary immunodeficiency diseases (PIDs) and other monogenic disorders.

Efficiency of autologous stem cell collection: Comparison of three different cell separators

Peripheral blood progenitor cells (PBPC) infusion allows rapid haematological recovery after high dose chemotherapy. Efficient PBPC collection is therefore essential as rescue therapy for transplantation. In order to validate a new equipment (ComTec^®, Fresenius Kabi), we compared the efficiency of three cell separators for PBPC collection in patients with haematological malignant diseases. From June 2014 to December 2015, 83 PBPC were collected in 48 patients. Three aphaeresis machines were used: Cobe Spectra^® (Terumo BCT, 11), Amicus^® (Fenwall, 30), and ComTec^® (Fresenius Kabi, 42). The median collection efficiency was similar between the three separators. The evaluation of cell contamination in the final product revealed a lower red cell contamination with Spectra^® and ComTec^®, whereas the platelet contamination was lower with Amicus^®. The new equipment has been validated and can be further used in routine, with a total running cost that turned out to be quite lower. Each separator has its own characteristics and advantages. Further study is needed to suggest that the choice of separator could be guided following the patient's blood characteristics.

Comparison of two apheresis systems for autologous stem cell collections in pediatric oncology patients

BACKGROUND

Peripheral stem cell collections can be challenging in the pediatric population and respective experience is limited. Since February 2015 our institution is utilizing the new Spectra Optia (Optia) apheresis device, which has replaced the former COBE Spectra (COBE) device. As a quality initiative we collected and compared collection efficiency (CE2) and other collection variables between the two devices.

STUDY DESIGN AND METHODS

In this retrospective study we collected and compared clinical, laboratory, and technical collection data from stem cell collection procedures done with the Optia and COBE devices. The collected data included patient demographics, precollection peripheral CD34+ cell counts, total CD34+ cells collected, complete blood count, electrolytes before and after collection, side effects attributed to the collection, total blood volumes processed (TBVs), collection times, and calculated CE2 and collection ratios.

RESULTS

Forty-one collection procedures performed on 29 pediatric patients with the Optia device were compared to 41 collections performed on 27 patients with the COBE device. The TBVs through the Optia device were significantly smaller than the COBE (3.9 ± 0.2 × TBV vs. 5.5 ± 0.1 × TBV, respectively; p < 0.001), requiring significantly less anticoagulant and providing similar amounts of stem cells while collection times were significantly shorter (mean, 238 ± 9 min vs. 264 ± 9 min, respectively; p < 0.05). Collections on the Optia caused significantly smaller reductions of plasma calcium and magnesium. No significant side effects attributed to the procedure were noted.

CONCLUSION

Stem cell apheresis with the Optia device in children is safe and feasible with smaller blood volumes with shorter collection times.

Healthy donor hematopoietic stem cell mobilization with biosimilar granulocyte-colony-stimulating factor: safety, efficacy, and graft performance

BACKGROUND

Biosimilar granulocyte-colony-stimulating factors (G-CSFs) have been available in the European Union since 2008, and Sandoz' biosimilar filgrastim was approved in the United States in March 2015 for all of the reference product's indications except acute radiation syndrome. Biosimilar G-CSFs have been largely embraced by the medical community, except for some reservations about healthy-donor stem cell mobilization, for which use outside of clinical studies was cautioned against by some members of the scientific community.

STUDY DESIGN AND METHODS

In a two-center safety surveillance study (National Clinical Trial NCT01766934), 245 healthy volunteer stem cell donors were enrolled. Of 244 donors who began mobilization with twice-daily Sandoz biosimilar filgrastim, 242 received a full (n = 241) or partial (n = 1) course of G-CSF and underwent apheresis. Efficacy and safety were assessed and are reported here.

RESULTS

Biosimilar filgrastim was accompanied by the typical G-CSF class-related adverse effects of expected frequency and severity. Median mobilization for CD34-positive stem cells was 97/µL (range, 20-347/µL); after one apheresis (91%) or two aphereses (9%) from all but three donors (1.2%), cell doses in excess of the typical 4 × 10⁶ CD34-positive cells/kg of the recipient had been collected (range, 3-52 × 10⁶ /kg). Biochemical and hematologic alterations were consistent with previous reports; all had normalized by the first follow-up 1 month after mobilization. Stem cell products engrafted with typical probability and kinetics for G-CSF-mobilized stem cell products.

CONCLUSION

These data support the use of biosimilar filgrastim for healthy-donor stem cell mobilization as safe and effective.

Prospective randomized and crossover comparison of two apheresis machines for peripheral blood stem cell collection: a multicenter study

BACKGROUND

Improving apheresis technology may lead to an efficient and safe peripheral blood stem cell (PBSC) collection. Recently, the Spectra Optia (Optia, Terumo BCT) was introduced as an automated apheresis instrument, but comparisons with other instruments have been few. This is the first randomized multicenter and crossover comparison of the Optia with the automated program of the established apheresis instrument, the Spectra (Spectra-Auto, Terumo BCT).

STUDY DESIGN AND METHODS

A total of 233 apheresis procedures performed in 46 autologous patients and 108 allogeneic donors were investigated. Apheresis performed in the first day for all subjects using the Spectra-Auto (n = 79) and the Optia (n = 75) were evaluated as first-day analysis. Seventy-nine subjects, who required another session on the second day, underwent apheresis using the other instrument than the first-day instrument and were compared with each other in a paired crossover analysis.

RESULTS

The two instruments processed similar volumes with comparable run times and volumes of acid-citrate-dextrose used. The volumes of collected products were greater in the Optia. Yields of mononuclear cells and CD34+ cells were not different, but collection efficiencies were higher in the Optia (p = 0.008 in CE1 of crossover analysis). Spectra-Auto-collected products contained more contaminating red blood cells (RBCs), whereas there was a trend of more contaminating platelets (PLTs) in the Optia-collected products. Slight reductions were noted in the RBC or PLT counts of subjects who underwent apheresis with the Spectra-Auto or the Optia, respectively.

CONCLUSION

The Optia is safe and more efficient in the PBSC collection compared with the Spectra-Auto.

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

Peripheral blood stem cells from healthy donors mobilized by granulocyte colony-stimulating factor (G-CSF) and harvested by leukapheresis are commonly used for allogeneic stem cell transplantation. The frequency of severe graft versus host disease is similar for patients receiving peripheral blood and bone marrow allografts, even though the blood grafts contain more T cells, indicating mobilization-related immunoregulatory effects. The regulatory phosphoprotein osteopontin was quantified in plasma samples from healthy donors before G-CSF treatment, after four days of treatment immediately before and after leukapheresis, and 18–24 h after apheresis. Myeloma patients received chemotherapy, combined with G-CSF, for stem cell mobilization and plasma samples were prepared immediately before, immediately after, and 18–24 h after leukapheresis. G-CSF treatment of healthy stem cell donors increased plasma osteopontin levels, and a further increase was seen immediately after leukapheresis. The pre-apheresis levels were also increased in myeloma patients compared to healthy individuals. Finally, in vivo G-CSF exposure did not alter T cell expression of osteopontin ligand CD44, and in vitro osteopontin exposure induced only small increases in anti-CD3- and anti-CD28-stimulated T cell proliferation. G-CSF treatment, followed by leukapheresis, can increase systemic osteopontin levels, and this effect may contribute to the immunomodulatory effects of G-CSF treatment.

Comparison between intermittent and continuous spectra optia leukapheresis systems for autologous peripheral blood stem cell collection

Terumo BCT recently introduced a new system for mononuclear cell (MNC) collection that uses a Spectra Optia apheresis machine equipped with a redesigned disposable kit and software program (version 11.2). It allows for the continuous collection of MNCs, unlike the original Spectra Optia system (version 7.2), which included a chamber for two-step cell separation. The aim of this study was to compare the two apheresis systems in regard to specific performance parameters. A retrospective data analysis of 150 patients who had undergone peripheral blood stem cell collection between March of 2014 and May of 2015 at our institution was performed. For the matched comparison, patients were divided into two groups by diagnosis and by previous forms of therapy received: a homogeneous group of patients with multiple myeloma (MM) that had received first line therapy ("MM" group, n = 88) and a heterogeneous group that included all of the other patients ("other" group, n = 62). No significant differences in CD34+ collection yields between both collection regimens were found (p_MM  = 0.19, p_other  = 0.74) in either group. Moreover, similar performance ratios (collected/predicted CD34+ cell number in %) were observed (p_MM  = 0.89, p_other  = 0.1). No relevant variations in platelet or hemoglobin loss were found between the two systems. We conclude that the new continuous Spectra Optia MNC system is equally efficient in collecting CD34+ cells and can be used without sacrificing collection efficiency levels when treating a broad variety of autologous patients. J. Clin. Apheresis 32:27-34, 2017. © 2016 Wiley Periodicals, Inc.

CAR-T Cell Therapies From the Transfusion Medicine Perspective

The use of chimeric antigen receptor (CAR)-T cell therapy for the treatment of hematologic malignancies has generated significant excitement over the last several years. From a transfusion medicine perspective, the implementation of CAR-T therapy as a potential mainstay treatment for not only hematologic but also solid-organ malignancies represents a significant opportunity for growth and expansion. In this review, we will describe the rationale for the development of genetically redirected T cells as a cancer therapeutic, the different elements that are required to engineer these cells, as well as an overview of the process by which patient cells are harvested and processed to create and subsequently validate CAR-T cells. Finally, we will briefly describe some of the toxicities and clinical efficacy of CAR-T cells in the setting of patients with advanced malignancy.

An innovative method to generate a Good Manufacturing Practice-ready regulatory T-cell product from non-mobilized leukapheresis donors

BACKGROUND AIMS

There is real and sustained interest in preparing T-regulatory cells from leukapheresis collections for cellular therapy through the use of simple, effective and reliable methods conforming to Good Manufacturing Practice (GMP). We describe a GMP-ready isolation procedure for CD25(+) products with the use of a sterile docking device, pigtail sampling, a laminar flow hood and the CliniMACS system that uses leukapheresis collections made by two apheresis machines.

METHODS

We used CD8/CD19 depletion followed by CD25-positive selection. The median number of CD4(+) cells recovered was 72.5 ± 32.6 × 10(6), of which 60.5% ± 17.8% were CD25(+)FOXP3(+) cells. Suppression of autologous CD25(-) cell proliferation by the cryopreserved CD25(+) products was 51.3% ± 4.4%, 49.0% ± 3.7% and 39.0% ± 3.6% at CD25(+):CD25(-) ratios of 1:1, 1:2 and 1:4 (n = 6), respectively, comparable to suppression by fresh CD25(+) products (53% ± 6.2%, 51% ± 3.3% and 39% ± 7.1%).

RESULTS

We found Leukapheresis collections by Cobe Spectra contained more lymphocytes and platelets than collections by Spectra Optia apheresis machine (median, 9.2 × 10(9) versus 6.7 × 10(9); P = 0.04) and platelets (median, 610 × 10(9) versus 170 × 10(9); P = 0.04). The frequency of CD4(+)CD25(+)FOXP3(+) was significantly higher in the leukapheresis (4.85%; 95% confidence interval, 1.95% to 5.38%) than in peripheral blood (3.9%; 95% confidence interval, 2.63% to 6.45%) (P = 0.02). The CD8- and CD19-negative depletion step was associated with significant loss of total CD4(+) T cells (P = 0.001).

CONCLUSIONS

Results suggest that functional CD25(+) products can be isolated with a GMP-ready method, and good recovery can be obtained with the use of an optimized cryopreservation protocol. These data and methods show the potential, possibilities and future work needed to isolate target cell populations in a reproducible, time-efficient and cost-efficient manner for clinical applications.

Automation of cellular therapy product manufacturing: results of a split validation comparing CD34 selection of peripheral blood stem cell apheresis product with a semi-manual vs. an automatic procedure

Background

Automation of cell therapy manufacturing promises higher productivity of cell factories, more economical use of highly-trained (and costly) manufacturing staff, facilitation of processes requiring manufacturing steps at inconvenient hours, improved consistency of processing steps and other benefits. One of the most broadly disseminated engineered cell therapy products is immunomagnetically selected CD34+ hematopoietic “stem” cells (HSCs).

Methods

As the clinical GMP-compliant automat CliniMACS Prodigy is being programmed to perform ever more complex sequential manufacturing steps, we developed a CD34+ selection module for comparison with the standard semi-automatic CD34 “normal scale” selection process on CliniMACS Plus, applicable for 600 × 10⁶ target cells out of 60 × 10⁹ total cells. Three split-validation processings with healthy donor G-CSF-mobilized apheresis products were performed; feasibility, time consumption and product quality were assessed.

Results

All processes proceeded uneventfully. Prodigy runs took about 1 h longer than CliniMACS Plus runs, albeit with markedly less hands-on operator time and therefore also suitable for less experienced operators. Recovery of target cells was the same for both technologies. Although impurities, specifically T- and B-cells, were 5 ± 1.6-fold and 4 ± 0.4-fold higher in the Prodigy products (p = ns and p = 0.013 for T and B cell depletion, respectively), T cell contents per kg of a virtual recipient receiving 4 × 10⁶ CD34+ cells/kg was below 10 × 10³/kg even in the worst Prodigy product and thus more than fivefold below the specification of CD34+ selected mismatched-donor stem cell products. The products’ theoretical clinical usability is thus confirmed.

Conclusions

This split validation exercise of a relatively short and simple process exemplifies the potential of automatic cell manufacturing. Automation will further gain in attractiveness when applied to more complex processes, requiring frequent interventions or handling at unfavourable working hours, such as re-targeting of T-cells.

Automated CD34+ cell isolation of peripheral blood stem cell apheresis product

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.

Hematopoietic stem and progenitor cell harvesting: technical advances and clinical utility

Hematopoietic stem and progenitor cell (HSPC) transplantations require prior harvesting of allogeneic or autologous HSPCs. HSPCs are usually present in bone marrow (BM) during the entire life, in cord blood (CB) at birth, or in peripheral blood (PB) under particular circumstances. HSPCs were first harvested in BM and later in CB and PB, as studies showed interesting features of such grafts. All harvesting methods were in use throughout the years, except BM harvesting for HSPC autologous transplantation, which was replaced by PB harvesting. BM, CB, and PB harvesting methods have been developed, and materials and devices technically improved to increase the number of HSPCs harvested. In parallel, knowing the features of the donors or patients associated with successful numbers of HSPCs allows the adaptation of appropriate harvesting methods. Moreover, it is important to ensure the safety of donors or patients while harvesting. This review describes the methods used for harvesting based on recent studies or developments around these methods, and more particularly, the means developed to increase the numbers of HSPCs harvested in each method. It also explains briefly the influence of technical improvements in HSPC harvesting on potential changes in HSPC graft composition.

Red blood cell depletion from bone marrow and peripheral blood buffy coat: a comparison of two new and three established technologies

BACKGROUND

Red blood cell (RBC) depletion is a standard technique for preparation of ABO-incompatible bone marrow transplants (BMTs). Density centrifugation or apheresis are used successfully at clinical scale. The advent of a bone marrow (BM) processing module for the Spectra Optia (Terumo BCT) provided the initiative to formally compare our standard technology, the COBE2991 (Ficoll, manual, "C") with the Spectra Optia BMP (apheresis, semiautomatic, "O"), the Sepax II NeatCell (Ficoll, automatic, "S"), the Miltenyi CliniMACS Prodigy density gradient separation system (Ficoll, automatic, "P"), and manual Ficoll ("M"). C and O handle larger product volumes than S, P, and M.

STUDY DESIGN AND METHODS

Technologies were assessed for RBC depletion, target cell (mononuclear cells [MNCs] for buffy coats [BCs], CD34+ cells for BM) recovery, and cost/labor. BC pools were simultaneously purged with C, O, S, and P; five to 18 BM samples were sequentially processed with C, O, S, and M.

RESULTS

Mean RBC removal with C was 97% (BCs) or 92% (BM). From both products, O removed 97%, and P, S, and M removed 99% of RBCs. MNC recovery from BC (98% C, 97% O, 65% P, 74% S) or CD34+ cell recovery from BM (92% C, 90% O, 67% S, 70% M) were best with C and O. Polymorphonuclear cells (PMNs) were depleted from BCs by P, S, and C, while O recovered 50% of PMNs. Time savings compared to C or M for all tested technologies are considerable.

CONCLUSION

All methods are in principle suitable and can be selected based on sample volume, available technology, and desired product specifications beyond RBC depletion and MNC and/or CD34+ cell recovery.