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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 × 10 6 CD34-positive cells/kg of the recipient had been collected (range, 3-52 × 10 6 /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., (© 2016 The Authors. Transfusion published by Wiley Periodicals, Inc. on behalf of AABB.)

Background: Cryopreserved hematopoietic progenitor cells collected by apheresis from granulocyte-colony-stimulating factor with or without chemotherapy-mobilized patients have become the preferred type of autograft to support treatment of diseases amenable to high-dose chemotherapy. A novel apheresis system, the Spectra Optia v.5.0 (CaridianBCT), was constructed to meet certain shortcomings of manual apheresis systems such as the COBE Spectra MNC (CaridianBCT), including the need for continuous optical or manual monitoring and readjustment of buffy coat position and sensitivity to inconsistent blood flow. By use of optical sensors, which provide real-time automatic interface (buffy coat) and collection line control, the Spectra Optia promises to automatically guide apheresis procedures, potentially freeing up operator time and reducing variability in collection efficiency (CE2)., Study Design and Methods: In a two-center clinical trial, 35 autologous stem cell donors were subjected to apheresis with the Spectra Optia to validate feasibility and effectiveness of apheresis procedures. Results were compared to data from 80 autologous apheresis procedures with the COBE Spectra MNC., Results: Usability and function of the automatic interface management were excellent. CD34+ cell quality, assessed by viability staining, colony-forming unit-culture frequency, and engraftment kinetics, was equally good with both systems. CE2 of the Spectra Optia, calculated as CD34+ contents in the product divided by the number of CD34+ cells presented to the collection port, exceeded that of the COBE Spectra MNC. Spectra Optia product volumes were significantly smaller. Very high white blood cell and platelet counts modestly reduced CE2 with the Spectra Optia., Conclusion: The Spectra Optia is a novel automatic apheresis system supporting autologous stem cell collection with at least equal efficiency and superior user-friendliness compared to the COBE Spectra MNC., (© 2010 American Association of Blood Banks.)

Background: Cytomegalovirus (CMV) disease constitutes a serious complication after allogeneic stem cell transplantation. For the clearance of CMV, CD8+ T cells are pivotal., Study Design and Methods: Here, the novel streptamer technology was used at good manufacturing practice (GMP) level for adoptive transfer of CMV-specific T cells into acute leukemia patients with recurrent high CMV antigenemia after allogeneic stem cell transplantation., Results: After a single transfusion, the frequency of CMV-specific CD8+CD45RA+CCR7- effector T cells increased dramatically from 0.0% to a maximum of 27.1% of all T cells. These T cells were clearly donor derived and did not stem from intrinsic reconstitution, as demonstrated by analysis of 1) donor chimerism through single-tandem repeats, 2) T-cell receptor excision circles, and 3) Vβ-chain typing by polymerase chain reaction. Clinically, the specific T-cell transfer resulted in a persistent clearance of the CMV antigenemia, which allowed the patients to discontinue toxic antiviral drug therapy without further high-level reactivation of CMV, demonstrating the power of the streptamer technology., Conclusion: Taken together, the streptamer technology offers the advantage of selecting virus-specific CD8+ T cells at GMP level for adoptive T-cell transfer, thus inducing long-lasting specific CD8+ T-cell responses without increasing the risk for graft-versus-host disease., (© 2010 American Association of Blood Banks.)

Background: Dendritic cells (DCs) generated from leukemic blasts constitute a promising tool in immunotherapy for acute myeloid leukemia patients (AML-DCs), because AML-DCs express human leukocyte antigens and costimulatory molecules such as CD40, CD80, and CD86 at a higher level than leukemic blasts. Potentiation of AML-DC vaccine might become feasible by the addition of adjuvants such as lipopolysaccharides (LPS) or CPG-rich oligodeoxyribonucleotides binding to Toll-like receptors (TLR) and inducing a stronger Type 1 T-cell response., Study Design and Methods: mRNA and protein expression of TLR-2, -4, and -9 were analyzed with quantitative real-time polymerase chain reaction, Western blot, and flow cytometry for mature monocyte-derived DCs generated from 14 AML patients versus 14 healthy volunteers (HV-DCs), and the response of the AML- and HV-DCs to different microbial TLR ligands was determined by enzyme-linked immunosorbent assay for the proinflammatory cytokines tumor necrosis factor (TNF)-alpha, inducible protein (Ip)-10, and interleukin (IL)-6., Results: AML-DCs and HV-DCs strongly expressed TLR-2 and TLR-4, while TLR-9 was expressed at a lower level in both groups. There was no significant difference in TLR expression between the two groups of AML-DCs and HV-DCs. In accordance with the TLR expression levels, DCs generated from both AML patients and HVs responded to the known microbial ligands peptidoglycan (PGN) and lipoteichoic acid for TLR-2 and LPS as ligand for TLR-4, by producing TNF-alpha and IL-6. A response to the ODNs 2006 and 2216 binding to TLR-9 was only detected in AML-DCs., Conclusion: Microbial ligands like ODNs and LPS constitute promising adjuvants for enhancing (AML-) DC vaccines.

Background: Mononuclear cells (MNCs) of severely impaired acute myeloid leukemia (AML) patients may be collected by leukapheresis for large-scale generation of dendritic cells (AML-DCs) under good manufacturing practice (GMP) conditions for adoptive immunotherapy., Study Design and Methods: In five end-stage AML patients, a leukapheresis procedure was performed with a cell separator (either COBE Spectra [Gambro BCT] or Amicus [Baxter]). For large-scale AML-DC generation, the MNCs of a single leukapheresis concentrate were isolated by density gradient and plated into a cell factory under GMP conditions. The AML-DCs were harvested on Day 8 of culture, and their viability, the mature morphology, and the phenotype were evaluated. The AML-DCs were injected subcutaneously into five AML patients up to four times at a biweekly interval., Results: All AML patients entered the leukapheresis procedure with a highly pathologic blood count. In a mean separation time of 198 +/- 33 minutes, a mean of 1.3 +/- 0.2-fold the total blood volume was processed with a white blood cell (WBC) yield of 9 x 10(9) to 70 x 10(9) per collection dependent on the precollection WBC count. After density gradient a mean of 2.2 x 10(9) +/- 0.3 x 10(9) MNCs were plated into a cell factory. This resulted in a mean viable and mature DC yield of 0.01 x 10(9) of MNCs., Conclusion: The leukapheresis procedure is a feasible and safe procedure even in patients with hematologic malignancies and highly pathologic blood counts. Sufficient amounts of MNCs can be collected in leukopenic patients and the large-scale generation of AML-DCs in cell factories under GMP conditions yields in an adequate quantity of viable and mature AML-DCs.