Blood component collection by apheresis

Expanding applications of allogeneic platelets, platelet lysates, and platelet extracellular vesicles in cell therapy, regenerative medicine, and targeted drug delivery

Platelets are small anucleated blood cells primarily known for their vital hemostatic role. Allogeneic platelet concentrates (PCs) collected from healthy donors are an essential cellular product transfused by hospitals to control or prevent bleeding in patients affected by thrombocytopenia or platelet dysfunctions. Platelets fulfill additional essential functions in innate and adaptive immunity and inflammation, as well as in wound-healing and tissue-repair mechanisms. Platelets contain mitochondria, lysosomes, dense granules, and alpha-granules, which collectively are a remarkable reservoir of multiple trophic factors, enzymes, and signaling molecules. In addition, platelets are prone to release in the blood circulation a unique set of extracellular vesicles (p-EVs), which carry a rich biomolecular cargo influential in cell-cell communications. The exceptional functional roles played by platelets and p-EVs explain the recent interest in exploring the use of allogeneic PCs as source material to develop new biotherapies that could address needs in cell therapy, regenerative medicine, and targeted drug delivery. Pooled human platelet lysates (HPLs) can be produced from allogeneic PCs that have reached their expiration date and are no longer suitable for transfusion but remain valuable source materials for other applications. These HPLs can substitute for fetal bovine serum as a clinical grade xeno-free supplement of growth media used in the in vitro expansion of human cells for transplantation purposes. The use of expired allogeneic platelet concentrates has opened the way for small-pool or large-pool allogeneic HPLs and HPL-derived p-EVs as biotherapy for ocular surface disorders, wound care and, potentially, neurodegenerative diseases, osteoarthritis, and others. Additionally, allogeneic platelets are now seen as a readily available source of cells and EVs that can be exploited for targeted drug delivery vehicles. This article aims to offer an in-depth update on emerging translational applications of allogeneic platelet biotherapies while also highlighting their advantages and limitations as a clinical modality in regenerative medicine and cell therapies.

Variation in activation marker expression within the platelet population - a new parameter for evaluation of platelet flow cytometry data

In flow cytometry, individual cells are investigated. Platelet activation is normally reported in form of percentage of platelets expressing the marker (positive platelets) and/or mean/median fluorescence intensity (MFI) for the entire analyzed population. None of these take into account the variance of the marker expression between individual platelets. This can be obtained as data on coefficient of variation (CV). This study explores if CV provides additional information regarding platelet function. Samples from platelet concentrates (PCs) prepared by apheresis- (n = 13) and interim platelet unit (IPU) technique (n = 26) and stored for 6-7 days were included and compared. Spontaneous- and agonist-induced expression of activation markers (fibrinogen binding and exposure of P-selectin, LAMP-1, and CD63) was investigated as percentage positive platelets, MFI and CV. Spontaneous expression of P-selectin as percentage positive platelets and MFI was higher for IPU PCs than apheresis PCs, which in contrast had higher agonist-induced activation. CV for spontaneous fibrinogen binding and P-selectin exposure was larger for apheresis PCs, while IPU PCs generally had larger CV for P-selectin, LAMP-1, and CD63 after agonist stimulation. Our findings show that CV adds additional information when assessing platelet activation by providing data on the variation in activation responses within the platelet population.

Can the administration of platelet lysates to the brain help treat neurological disorders?

Neurodegenerative disorders of the central nervous system (CNS) and brain traumatic insults are characterized by complex overlapping pathophysiological alterations encompassing neuroinflammation, alterations of synaptic functions, oxidative stress, and progressive neurodegeneration that eventually lead to irreversible motor and cognitive dysfunctions. A single pharmacological approach is unlikely to provide a complementary set of molecular therapeutic actions suitable to resolve these complex pathologies. Recent preclinical data are providing evidence-based scientific rationales to support biotherapies based on administering neurotrophic factors and extracellular vesicles present in the lysates of human platelets collected from healthy donors to the brain. Here, we present the most recent findings on the composition of the platelet proteome that can activate complementary signaling pathways in vivo to trigger neuroprotection, synapse protection, anti-inflammation, antioxidation, and neurorestoration. We also report experimental data where the administration of human platelet lysates (HPL) was safe and resulted in beneficial neuroprotective effects in established rodent models of neurodegenerative diseases such as Parkinson's disease, Alzheimer's disease, traumatic brain injury, and stroke. Platelet-based biotherapies, prepared from collected platelet concentrates (PC), are emerging as a novel pragmatic and accessible translational therapeutic strategy for treating neurological diseases. Based on this assumption, we further elaborated on various clinical, manufacturing, and regulatory issues that need to be addressed to ensure the ethical supply, quality, and safety of HPL preparations for treating neurodegenerative and traumatic pathologies of the CNS. HPL made from PC may become a unique approach for scientifically based treatments of neurological disorders readily accessible in low-, middle-, and high-income countries.

Recovery of platelet-rich red blood cells and acquisition of convalescent plasma with a novel gravity-driven blood separation device

Objectives

Our objectives were to determine the separation characteristics and blood product quality of a gravity‐driven microfiltration blood separation system (HemoClear, The Netherlands).

Background

A range of centrifugal blood separation devices, including intraoperative cell salvage devices (cell savers) and apheresis machines, are available to assist in preparing both allogenic and autologous blood products. These devices are expensive to operate and require extensive training.

Methods and Materials

Nine whole blood units were collected under standard conditions and analysed for haematological parameters, thromboelastographic properties, platelet morphology and activation, and red blood cell (RBC) deformability and morphology. Three whole blood units were separated by means of the HemoClear device, into a liquid and cellular component. The cellular component was diluted with SAGM and cold stored for 14 days. To simulate cell salvage six whole blood units were diluted with isotonic saline, followed by multiple HemoClear separation rounds.

Results

The recovery of both RBCs (100 ± 1.6%) and white blood cells (99 ± 4.5%) after undiluted filtration were very high, while platelet recovery was high (83 ± 3.0%). During the filtration, and cold storage after filtration storage both the non‐deformable RBC fraction and the RBC maximum elongation remained stable. Parameters of thromboelastography indicated that platelets remain functional after filtration and after 7 days of cold storage. In the cell salvage simulation the total protein load in the cellular fraction was reduced by 65 ± 4.1% after one washing round and 84 ± 1.9% after two consecutive washing rounds.

Conclusion

The novel blood filter studied effectively separates whole blood into diluted plasma and platelet‐rich RBCs. Moreover, the device effectively washed diluted whole blood, driving over 80% of proteins to the liquid component.

Mass-tag barcoding for multiplexed analysis of human synaptosomes and other anuclear events

Mass-tag cell barcoding has increased the throughput, multiplexing, and robustness of multiple cytometry approaches. Previously, we adapted mass cytometry for cells to analyze synaptosome preparations (mass synaptometry or SynTOF), extending mass cytometry to these smaller, anuclear particles. To improve throughput and individual event resolution, we report here the application of palladium-based barcoding in human synaptosomes. Up to 20 individual samples, each with a unique combinatorial barcode, were pooled for labeling with an antibody cocktail. Our synaptosome protocol used six palladium-based barcoding reagents, and in combination with sequential gating increased the identification of presynaptic events approximately fourfold. These same parameters also efficiently resolved two other anuclear particles: human red blood cells and platelets. The addition of palladium-based mass-tag barcoding to our approach improves mass cytometry of synaptic particles.

Aggregates in blood filter chambers used from the plasma donations of anti-D donors: evaluation for monoclonal antibody discovery using phage display

BACKGROUND

RhD-immunoglobulin (RhIg) prevents anti-D alloimmunisation in D-negative pregnant women when the fetus is D-positive, reducing the incidence of haemolytic disease of the fetus and newborn. Manufacturing RhIg is reliant on the limited supply of plasma donations with anti-D antibodies. Monoclonal antibody (mAb) development platforms such as phage display, require blood samples to be collected from anti-D donors, which may be a complicated process. The blood filter chamber (BFC) discarded after an anti-D donor's donation might provide a source of Ig-encoding RNA. This study aims to evaluate whether used BFCs are a suitable source of Ig-encoding RNA for phage display.

MATERIAL AND METHODS

Haemonetics PCS2 BFCs were obtained from 10 anti-D donors for total RNA extraction, cDNA synthesis and amplification of VH and VL IgG sequences for assembly of single-chain variable fragments (scFvs). A scFv-phage display library was constructed and 3 rounds of biopanning were performed using D-positive and D-negative red blood cells (RBCs). Positive phage clones were isolated, Sanger sequenced and, where possible, reformatted into full-length human IgGs to define specificity. The BFC aggregates from 2 anti-D donors underwent a Wright-Giemsa stain and hematological cell count.

RESULTS

Of 10 BFCs, a sufficient yield of total RNA for library construction was obtained from BFCs containing cellular aggregates (n=5). Aggregate analysis showed lymphocytes were the cellular source of Ig-encoding RNA. From the 5 samples with aggregates, scFvs were assembled from amplified IgG variable regions. The library constructed from 1 of these samples resulted in the isolation of clones binding to D-positive RBCs with IGHV3 gene usage. Of the 4 reformatted IgG, 3 were anti-D and 1 had undefined specificity.

DISCUSSION

BFC aggregates are a new and convenient source of Ig-encoding RNA which can be used to construct Ig gene libraries for mAb isolation and discovery via antibody phage display.

A comparative study of five plateletpheresis machines in a tertiary care center of India: AmiCORE vs COM.TEC vs Haemonetics MCS+ vs Spectra Optia vs Trima Accel

BACKGROUND

Single donor apheresis platelets are superior in quality, but their usage is limited in a developing country due to cost and time constraints. Hence the product obtained must exceed in terms of yield, donor safety and technical convenience. Previous literature available on cell separators is on older versions.

AIMS

Prospective comparison of 5 latest cell separators (AmiCORE, COM.TEC, Haemonetics MCS+, SpectraOptia and TrimaAccel) for product yield, performance variables and donor adverse effects.

MATERIAL & METHODS

From October 2019 - March 2020, 1108 donors were randomly allotted to a cell separator. Post-donation sample was taken from the donor 15-20 minutes after procedure completion. The platelet yield from the product collected was measured twice (day 0 and day 1). Donor demography, pre-and post-procedural donor peripheral blood values, performance and product variables were statistically analyzed.

RESULTS

AmiCORE had an optimal collection efficacy (44.6%) and collection rate (0.037 x 1011/minute). Haemonetics MCS+ had a better collection efficacy (48.4%) and rate (0.038 x 1011/minute). Spectra Optia achieved least procedural time (59.5 minutes), donor adverse effects (6.3%); highest collection efficacy (52.8%) and rate (0.056 x 1011/minute). Trima Accel achieved highest collection rate (0.056 x 1011/minute) and the least product volume (228 ml).

CONCLUSION

Highest collection efficacy was achieved by Trima Accel, highest collection rate by Trima Accel and Spectra Optia, lowest donor adverse effects by Spectra Optia and least number of procedural troubleshooting by COM.TEC. Apart from this, fiscal factors and service availability also need to be considered before choosing a cell separator.

Comparison of the platelet activation status of single-donor platelets obtained with two different cell separator technologies

BACKGROUND

The microparticle content (MP%) of apheresis platelets-a marker of platelet activation-is influenced by donor factors and by external stressors during collection and storage. This study assessed the impact of apheresis technology and other factors on the activation status (MP%) of single-donor apheresis platelets.

STUDY DESIGN AND METHODS

Data from six US hospitals that screened platelets by measuring MP% through dynamic light scattering (ThromboLUX) were retrospectively analyzed. Relative risks (RRs) were derived from univariate and multivariable regression models, with activation rate (MP% ≥15% for plasma-stored platelets; ≥10% for platelet additive solution [PAS]-stored platelets) and MP% as outcomes. Apheresis platform (Trima Accel vs Amicus), storage medium (plasma vs PAS), pathogen reduction, storage time, and testing location were used as predictors.

RESULTS

Data were obtained from 7511 platelet units collected using Trima (from 16 suppliers, all stored in plasma, 20.0% were pathogen-reduced) and 2456 collected using Amicus (from four different collection facilities of one supplier, 65.0% plasma-stored, 35.0% PAS-stored, none pathogen-reduced). Overall, 30.0% of Trima platelets were activated compared to 45.6% of Amicus platelets (P < .0001). Multivariable analysis identified apheresis platform as significantly associated with platelet activation, with a lower activation rate for Trima than Amicus (RR: 0.641, 95% confidence interval [CI]: 0.578; 0.711, P < .0001) and a 6.901% (95% CI: 5.926; 7.876, P < .0001) absolute reduction in MP%, when adjusting for the other variables.

CONCLUSION

Trima-collected platelets were significantly less likely to be activated than Amicus-collected platelets, irrespective of the storage medium, the use of pathogen reduction, storage time, and testing site.

Comparative assessment of single-donor plateletpheresis by Haemonetics® MCS® plus and Trima Accel®

BACKGROUND

Single-donor platelets (SDPs) prepared by sophisticated automated equipment offer several advantages over random-donor platelets and are being increasingly used to support thrombocytopenic patients. Different apheresis machines working on the principle of centrifugation are being used worldwide to collect platelets. This retrospective study was done to compare plateletpheresis on two automated cell seperators - Haemonetics^® MCS^® Plus and Trima Accel^®.

MATERIALS AND METHODS

Data for 100 single-donor plateletpheresis procedures, fifty on each machine, were retrospectively collected and analyzed. Donor characteristics were analyzed by Student's t-test and no significant difference was found between the two groups. The parameters compared between the two machines were yield, collection efficiency, blood volume processed, procedure time, acid-citrate-dextrose (ACD) used, leukodepletion achieved, quality control of the products, and adverse donor reactions.

RESULTS

Platelet yield (3.054 ± 0.14 vs. 3.120 ± 0.25), quality control of the platelets, leukodepletion achieved, and donor safety were comparable in both the machines. The blood volume processed (2230.74 ± 227.01 vs. 2452.90 ± 318.61), ACD used during procedure (265.48 ± 43.21 vs. 298.10 ± 53.32), procedural time (55.92 ± 13.00 vs. 68.86 ± 12.64), and the postprocedural decrease in donor count in Trima Accel^® (183.10 ± 23.99 vs. 161.44 ± 63.47) were significantly less than those in Haemonetics^® MCS^® Plus. The median collection efficiency of Trima Accel^® was found to be greater than Haemonetics^® MCS^® Plus (0.000649 vs. 0.000608, P = 0.020).

CONCLUSION

Both Trima Accel^® and Haemonetics^® MCS^® Plus can collect SDPs safely and efficiently. Trima Accel^® has higher collection efficiency and reduced incidence of citrate-related adverse effects. It also has better potential to optimize productivity due to decreased procedural time.

Analysis of Donor Safety in High Yield Plateletpheresis Procedures: An Experience from Tertiary Care Hospital in South India

The apheresis platelets are the preferred blood components for the thrombocytopenic hemato-oncology patients. The one of the important factors for post transfusion increment is the dose of the platelet product infused. The minimum platelet product yield is defined but the amount of maximum possible platelets collection from a single donor is not universally defined. There is lots of apprehension in our country for apheresis procedures harvesting more than a standard unit. This retrospective observational study was conducted to determine safety of high yield plateletapheresis collection among Indian donors This retrospective observational study was conducted for a period of 15 months including all consecutive plateletapheresis procedures. The informed consent had been obtained from all donors including high yield plateletapheresis (Yield ≥ 5 × 10¹¹). The apheresis product was subjected to platelet count. The donor adverse reactions were recorded along with procedural details. Post procedure complete blood count was done for the donors who consented for post procedure blood sample draw A total 569 procedures were performed during this period including 174 high yield procedure. The 526 procedures were analyzed for adverse donor reactions. The 43 were excluded for adverse donor reaction analysis due to yield less than 3 × 10¹¹ (n = 43). The adverse reactions rate between high yield procedures (18/174, 10.34%) and normal yield (20/352, 5.68%) were not statistically different (p = 0.052). The phlebotomy related complication (3.23%) followed by citrate toxicity (2.28%) were the two most common adverse reaction observed. The adverse reactions associated with high yield plateletapheresis procedures are comparable to normal yield procedures in term of overall adverse reactions observed and post procedural platelet counts. This can be beneficial to patients by providing products of greater yield.

Transfusion-Transmitted Infections Reported to the National Healthcare Safety Network Hemovigilance Module

Transfusion-transmitted infections (TTIs) can be severe and result in death. Transfusion-transmitted viral pathogen transmission has been substantially reduced, whereas sepsis due to bacterial contamination of platelets and transfusion-transmitted babesiosis may occur more frequently. Quantifying the burden of TTI is important to develop targeted interventions. From January 1, 2010, to December 31, 2016, health care facilities participating in the National Healthcare Safety Network Hemovigilance Module monitored transfusion recipients for evidence of TTI and recorded the total number of units transfused. Facilities use standard criteria to report TTIs. Incidence rates of TTIs, including for bacterial contamination of platelets and transfusion-transmitted babesiosis, are presented. One hundred ninety-five facilities reported 111 TTIs and 7.9 million transfused components to the National Healthcare Safety Network Hemovigilance Module. Of these 111 reports, 54 met inclusion criteria. The most frequently reported pathogens were Babesia spp in RBCs (16/23, 70%) and Staphylococcus aureus in platelets (12/30, 40%). There were 1.95 (26 apheresis, 4 whole blood derived) TTIs per 100 000 transfused platelet units and 0.53 TTI per 100 000 transfused RBC components, compared to 0.68 TTI per 100 000 all transfused components. Bacterial contamination of platelets and transfusion-transmitted babesiosis were the most frequently reported TTIs. Interventions that reduce the burden of bacterial contamination of platelets, particularly collected by apheresis, and Babesia transmission through RBC transfusion would reduce transfusion recipient morbidity and mortality. These analyses demonstrate the value and importance of facility participation in national recipient hemovigilance using standard reporting criteria.

An Innovative Standard Operation Procedure for Isolating GMP-Grade CD4+CD25+ T Cells from Non-Mobilized Leukapheresis

This SOP describes a closed system for isolating GMP-grade CD4⁺CD25⁺ T cells from non-mobilized leukapheresis collections (nMLCs), independent of a clean room in a certified GMP premises, by using CliniMACS format GMP grade reagents (CD25-labeled magnetic beads with/without pre-depletion of CD8⁺ T cells and CD19⁺ B cells), a GMP grade-A laminar hood and CliniMACS cell processing system.

Impact of frequent apheresis blood donation on bone density: A prospective, longitudinal, randomized, controlled trial

Background

Blood for transfusion is lifesaving and essential to many elements of modern medical practice. The global blood supply relies on volunteer blood donors. Apheresis is increasingly used to collect blood and requires anticoagulant to prevent extracorporeal coagulation. Citrate, the standard apheresis anticoagulant, chelates ionized calcium with consequent perturbations of serum calcium, parathyroid hormone, vitamin D, and markers of bone remodeling in donors. Cross-sectional studies of bone mineral density (BMD) among apheresis donors exhibit conflicting results.

Methods

The longitudinal, randomized, controlled ALTRUYST trial (NCT02655055) was undertaken to determine whether BMD declined following high frequency apheresis blood donation over 1 year. The study was powered at 80% to detect the primary outcome of a 3% decline in BMD. Subjects new to apheresis agreed to make ≥20 apheresis donations in a one-year period and were randomized to treatment (high frequency apheresis) or control (no apheresis). Dual-energy x-ray absorptiometry was performed before and after participation. Two-sided t-test and multivariable logistic regression were used to assess outcomes.

Findings

Mean lumbar spine BMD did not change during the study among control donors (−0.002 g/cm², 95%CI [−0.020, 0.016], p = 0.78), or among donors in the apheresis arm (mean change = 0.007 g/cm², 95%CI [−0.005, 0.018], p = 0.24). Mean total hip BMD did not change for control donors (mean change = 0.002 g/cm², 95%CI [−0.006, 0.009], p = 0.63) or apheresis donors (−0.004 g/cm², 95%CI [−0.10, 0.002], p = 0.16). Tests for differences in proportions of donors with change in BMD exceeding the least significant change at the lumbar spine in either a positive [8 apheresis (31%), 4 control (27%), p = 0.78] or negative direction [4 apheresis (15%), 5 control (33%)] were statistically non-significant (p = 0.18). Proportional increases [0 apheresis (0%), 1 control (7%), p = 0.18] and decreases [3 apheresis (12%), 1 control (14%)] were also not significantly different at the total hip (p = 0.61).

Interpretation

ALTRUYST is the first longitudinal trial to demonstrate that apheresis blood collection guidelines in the United States adequately protect the skeletal health of male volunteer blood donors.

Funding

Marquette University and the BloodCenter Research Foundation.

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ALTRUYST (NCT02655055) was a prospective RCT.

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It tested if BMD declined following high frequency apheresis blood donation.

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High frequency apheresis blood donation did not affect lumbar spine BMD.

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High frequency apheresis blood donation did not affect total hip BMD.

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High frequency apheresis blood donation did not affect trabecular bone score.

Immature Platelet Count Levels as a Novel Quality Marker in Plateletpheresis

The efficiency of plateletpheresis was improved owing to new developments in automated cell separators in the past decades. Nowadays multiple units of plateletpheresis products can be taken per collection from single donor and new parameters such as immature platelet fraction (IPF), immature platelet count (IPC) can be detected practically by automated hematology analyzers. Our aim is to find out a new quality parameter for evaluation of plateletpheresis by analyzing the platelet indices of donor and also to predict platelet recovery in recipients thereby preventing unnecessary platelet transfusion. In this study 104 platelet apheresis procedures were performed on the Trima Accel cell separator. Complete blood counts of donors and recipients were analyzed by Sysmex XN-1000 automated blood cell counter by means of quality parameters such as platelet count, IPF, IPC, mean platelet volume, platelet distribution width. We analyzed these parameters in the follow up after the transfusion of plateletpheresis and evaluated them as quality markers in the assessment of plateletpheresis effectiveness. For recipients of both single and double unit apheresis platelet transfusions, the pre-apheresis donor IPC correlated significantly with 1st and 24th hour recipient IPC values (p values < 0.05 for all comparisons). A-IPC as well as % change in IPF can be used to determine the quality of plateletpheresis in conjunction with platelet number in terms of evaluation of donors and also in the follow up of recipients undergoing platelet transfusion.

Quantity, quality, and functionality of peripheral blood cells derived from residual blood of different apheresis kits

BACKGROUND

Research with primary human white blood cell (WBC) subpopulations requires high quantity, quality, and functionality of peripheral blood mononuclear cells (PBMCs) as a source to further characterize cellular subpopulations such as T and B lymphocytes, monocytes, or natural killer cells. Apart from buffy coats derived from whole blood, residual blood from preparative hemapheresis kits are used as a source for PBMCs, but knowledge on the yield and functionality of cells from different devices is limited.

STUDY DESIGN AND METHODS

We evaluated quantity and quality of PBMCs isolated from apheresis kits of two apheresis devices (AMICUS, Fenwal; and Trima Accel, Terumo BCT), the latter being our standard source for many years. PBMCs derived from Trima or AMICUS were tested for yield and subtype composition by flow cytometry. Functionality was assessed by cytokine induction of CD4⁺ and CD8⁺ T cells and by degranulation. Moreover, cytotoxic activity of natural killer cells was quantified by a real-time killing assay.

RESULTS

Mean numbers of isolated cells were 5.5 ± 2.4 × 10⁸ for AMICUS, and 10.3 ± 6.4 × 10⁸ for Trima Accel, respectively. The proportion of WBC subtypes corresponded to well-known numbers from whole blood, with minor differences between the two apheresis systems. Likewise, minor differences in cytokine induction were found in stimulated CD4⁺ or CD8⁺ T cells. Finally, PBMCs derived from the two systems showed comparable cytotoxic activity.

CONCLUSION

PBMC derived from residual blood of the AMICUS and Trima Accel apheresis devices serve as an economic and easily accessible source for functional PBMCs with comparable quantity and quality to PBMCs derived from whole blood.

Comparison of Plateletpheresis on the Haemonetics and Trima Accel Cell Separators

The use of apheresis equipment to collect platelets has rapidly increased in recent years. We compared two apheresis instruments (Haemonetics MCS + and Trima Accel) with regard to platelet (PLT) yield and efficiency, and collection rate (CR) in a retrospective study. Overall 120 data obtained by Haemonetics and Trima systems (N = 60 for each) were randomly selected among 400 plateletpheresis procedures performed at the Apheresis Unit of Kayseri Education and Research Hospital between July 2016 and January 2017. The CR was significantly higher with the Haemonetics compared to the Trima (0.076 ± 0.016 vs. 0.065 ± 0.015 (PLT × 10¹¹ /min) respectively; P < 0.001). The PLT yield/unit was higher with the Haemonetics (4.4 ± 0.8 vs. 3.9 ± 0.8 × 10¹¹ , P = 0.001). Haemonetics and Trima Accel instruments collected platelets efficiently. We hope that these data will be a guide in selecting equipment for apheresis units.

Citrate anticoagulation: Are blood donors donating bone?

An estimated 2.4 million volunteer apheresis blood donation procedures were performed in the United States in 2010, and increases in the proportion of transfused blood products derived from apheresis blood collections have been consistently reported. Anticoagulation is required during apheresis and is achieved with citrate. Donor exposure to citrate causes an acute physiological response to maintain serum mineral homeostasis. Some data are available on the sequelae of this acute response in the days and weeks following exposure, raising questions about bone mineral density in regular apheresis donors. New research is emerging that addresses the potential long-term health outcomes of repeated citrate exposure. This article reviews the acute physiological response to citrate anticoagulation in volunteer blood donors, presents contrasting perspectives on the potential effects of citrate exposure on bone density, and identifies key knowledge gaps in our understanding of long-term health outcomes in apheresis donors. J. Clin. Apheresis 31:459-463, 2016. © 2015 Wiley Periodicals, Inc.

Comparison of plateletpheresis on the Fenwal Amicus, Fresenius COM.TEC, and Trima Accel Cell separators

Blood component donations by apheresis have become more common in modern blood transfusion practices. We compared three apheresis instruments (Fenwal Amicus, Fresenius COM.TEC, and Trima Accel) with regard to platelet (PLT) yield, collection efficiency (CE), and collection rate (CR). The single-needle or double-needle plateletpheresis procedures of the three instruments were compared in a retrospective, randomized study in 270 donors. The blood volume processed was higher in the COM.TEC compared with the Amicus and Trima. Also there was a significantly higher median volume of ACD used in collections on the COM.TEC compared with the Amicus and Trima. The PLT yield was significantly lower with the COM.TEC compared with the Amicus and Trima. Additionally, the CE was significantly lower with the COM.TEC compared with the Amicus and Trima. There was no significant difference in median separation time and CR between the three groups. When procedures were compared regarding CE by using Amicus device, it was significantly higher in single-needle than double-needle plateletpheresis. When double-needle Amicus system was compared with double-needle COM.TEC system, CE and PLT yield were significantly higher with Amicus system. When single-needle Amicus system was compared with single-needle Trima system, CE and PLT yield were significantly higher with Trima system. All instruments collected PLTs efficiently. However, the CE was lower with the COM.TEC compared with the Amicus and Trima. Also, we found Amicus single-needle system collected PLTs more efficiently compared with the double-needle system. CE and PLT yields were significantly higher with the single-needle Trima instrument compared with the single-needle Amicus device.

Comparison of double dose plateletpheresis on the Fenwal Amicus, Fresenius COM.TEC and Trima Accel cell separators

BACKGROUND

A variety of apheresis instruments are now available on the market for double dose plateletpheresis. We compared three apheresis devices (Fenwal Amicus, Fresenius COM.TEC and Trima Accel) with regard to processing time, platelet (PLT) yield, collection efficiency (CE) and collection rate (CR).

STUDY DESIGN AND METHODS

The single-needle or double-needle double plateletpheresis procedures of the three instruments were compared in a retrospective, randomized study in 135 donors.

RESULTS

In the pre-apheresis setting, 45 double plateletpheresis procedures performed with each instrument revealed no significant differences in donor's age, sex, weight, hemoglobin, white blood cell and PLT count between three groups. The blood volume processed to reach a target PLT yield of ≥ 6 × 10(11) was higher in the COM.TEC compared with the Amicus and Trima (4394 vs. 3780 and 3340 ml, respectively; p < 0.001). Also there was a significantly higher median volume of ACD used in collections on the COM.TEC compared with the Amicus and Trima (426 vs. 387 and 329 ml, respectively; p < 0.001). There was a significantly higher median time needed for the procedures on the COM.TEC compared with the Amicus and Trima (66 vs. 62 and 63 min, respectively; p = 0.024). The CE was significantly higher with the Trima compared with the Amicus and COM.TEC (83.57 ± 17.19 vs. 66.71 ± 3.47 and 58.79 ± 5.14%, respectively; p < 0.001). Also, there was a significantly higher product volume on the Trima compared with the Amicus and COM.TEC (395.56 vs. 363.11 and 386.4 ml, respectively; p = 0.008). Additionally, the CR was significantly lower with the COM.TEC compared with the Amicus and Trima (0.092 ± 0.011 vs. 0.099 ± 0.013 and 0.097 ± 0.013 plt × 10(11)/min, respectively; p = 0.039). There was no significant differences in PLT yield between the three groups (p = 0.636).

CONCLUSIONS

Trima single-needle device collected double dose platelets more efficiently than Amicus and COM.TEC double-needle devices. Blood volume processed, ACD-A volume, and median separation time was significantly higher with the COM.TEC. Also, the CR was significantly lower with the COM.TEC.

Comparison of double dose plateletpheresis on the Fenwal Amicus, Fresenius COM.TEC and Trima Accel cell separators

BACKGROUND

A variety of apheresis instruments are now available on the market for double dose plateletpheresis. We compared three apheresis devices (Fenwal Amicus, Fresenius COM.TEC and Trima Accel) with regard to processing time, platelet (PLT) yield, collection efficiency (CE) and collection rate (CR).

STUDY DESIGN AND METHODS

The single-needle or double-needle double plateletpheresis procedures of the three instruments were compared in a retrospective, randomized study in 135 donors.

RESULTS

In the pre-apheresis setting, 45 double plateletpheresis procedures performed with each instrument revealed no significant differences in donor's age, sex, weight, hemoglobin, white blood cell and PLT count between three groups. The blood volume processed to reach a target PLT yield of ≥ 6 × 10(11) was higher in the COM.TEC compared with the Amicus and Trima (4394 vs. 3780 and 3340 ml, respectively; p < 0.001). Also there was a significantly higher median volume of ACD used in collections on the COM.TEC compared with the Amicus and Trima (426 vs. 387 and 329 ml, respectively; p < 0.001). There was a significantly higher median time needed for the procedures on the COM.TEC compared with the Amicus and Trima (66 vs. 62 and 63 min, respectively; p = 0.024). The CE was significantly higher with the Trima compared with the Amicus and COM.TEC (83.57 ± 17.19 vs. 66.71 ± 3.47 and 58.79 ± 5.14%, respectively; p < 0.001). Also, there was a significantly higher product volume on the Trima compared with the Amicus and COM.TEC (395.56 vs. 363.11 and 386.4 ml, respectively; p = 0.008). Additionally, the CR was significantly lower with the COM.TEC compared with the Amicus and Trima (0.092 ± 0.011 vs. 0.099 ± 0.013 and 0.097 ± 0.013 plt × 10(11)/min, respectively; p = 0.039). There was no significant differences in PLT yield between the three groups (p = 0.636).

CONCLUSIONS

Trima single-needle device collected double dose platelets more efficiently than Amicus and COM.TEC double-needle devices. Blood volume processed, ACD-A volume, and median separation time was significantly higher with the COM.TEC. Also, the CR was significantly lower with the COM.TEC.

Preparation, quality criteria, and properties of human blood platelet lysate supplements for ex vivo stem cell expansion

Most clinical applications of human multipotent mesenchymal stromal cells (MSCs) for cell therapy, tissue engineering, regenerative medicine, and treatment of immune and inflammatory diseases require a phase of isolation and ex vivo expansion allowing a clinically meaningful cell number to be reached. Conditions used for cell isolation and expansion should meet strict quality and safety requirements. This is particularly true for the growth medium used for MSC isolation and expansion. Basal growth media used for MSC expansion are supplemented with multiple nutrients and growth factors. Fetal bovine serum (FBS) has long been the gold standard medium supplement for laboratory-scale MSC culture. However, FBS has a poorly characterized composition and poses risk factors, as it may be a source of xenogenic antigens and zoonotic infections. FBS has therefore become undesirable as a growth medium supplement for isolating and expanding MSCs for human therapy protocols. In recent years, human blood materials, and most particularly lysates and releasates of platelet concentrates have emerged as efficient medium supplements for isolating and expanding MSCs from various origins. This review analyzes the advantages and limits of using human platelet materials as medium supplements for MSC isolation and expansion. We present the modes of production of allogeneic and autologous platelet concentrates, measures taken to ensure optimal pathogen safety profiles, and methods of preparing PLs for MSC expansion. We also discuss the supply of such blood preparations. Produced under optimal conditions of standardization and safety, human platelet materials can become the future 'gold standard' supplement for ex vivo production of MSCs for translational medicine and cell therapy applications.

Donor Hemovigilance during Preparatory Plasmapheresis

BACKGROUND

Reports on unexpected donor events (UEs) during preparatory plasmapheresis (PPP) are scarce, and rarely consider technical UEs.

METHODS

Defined local and systemic UEs were graded by severity; technical UEs were not graded. On January 1, 2008, E.B.P.S.-Logistics (EBPS) installed the UE module for plasma management software (PMS). Donor room physicians entered UEs daily into the PMS. Medical directors reviewed entries quarterly. EBPS compiled data on donors, donations and UEs from January 1, 2008 to June 30, 2011.

RESULTS

66,822 UEs were observed during 1,107,846 PPPs for a corrected incidence of 6.55% (1.4% local, 0.55% systemic, 4.6% technical UEs). 3.36% of PPPs were accompanied by 1 UE and 1.18% by >1 UE (2-5). 13.7% of donors undergoing PPP for the first time, 9.7% of those having a second PPP and 4.0% of those having a third or more PPPs were associated with UEs. Most common UEs were repeated venipuncture, and broken-off collection due to venous access problems and small hematomas. Severe systemic UEs occurred at a rate of 36 per 100,000 PPPs.

CONCLUSIONS

Technical UEs were common with PPP. UEs accompanied first and second donations significantly more frequently than for subsequent donations.

Exploratory studies of extended storage of apheresis platelets in a platelet additive solution (PAS)

To evaluate the poststorage viability of apheresis platelets stored for up to 18 days in 80% platelet additive solution (PAS)/20% plasma, 117 healthy subjects donated platelets using the Haemonetics MCS+, COBE Spectra (Spectra), or Trima Accel (Trima) systems. Control platelets from the same subjects were compared with their stored test PAS platelets by radiolabeling their stored and control platelets with either (51)chromium or (111)indium. Trima platelets met Food and Drug Administration poststorage platelet viability criteria for only 7 days vs almost 13 days for Haemonetics platelets; ie, platelet recoveries after these storage times averaged 44 ± 3% vs 49 ± 3% and survivals were 5.4 ± 0.3 vs 4.6 ± 0.3 days, respectively. The differences in storage duration are likely related to both the collection system and the storage bag. The Spectra and Trima platelets were hyperconcentrated during collection, and PAS was added, whereas the Haemonetics platelets were elutriated with PAS, which may have resulted in less collection injury. When Spectra and Trima platelets were stored in Haemonetics' bags, poststorage viability was significantly improved. Platelet viability is better maintained in vitro than in vivo, allowing substantial increases in platelet storage times. However, implementation will require resolution of potential bacterial overgrowth during storage.

The post-platelet 100,000 count: effects of platelet collection and future

Currently, the majority of platelets transfused in the United States are collected by apheresis. The recent Food and Drug Administration guidance document published maintains that a postdonation platelet count for a donor remain >100,000/μL. During apheresis procedures, platelets are released from the splenic pool into circulation. This allows for higher postdonation platelet counts than anticipated. Some current plateletpheresis instruments take this into account when determining a safe product to be collected. On other instruments, the software does not allow for this correction. This may impact collections, but is expected to be resolved with a software update.

Preparation, storage and quality control of platelet concentrates

Patients with thrombocytopaenia need transfusions of platelet concentrates to prevent or stop bleeding. A platelet transfusion should provide platelets with good functionality. The quality of platelet concentrates (PCs) is affected by the preparation method and the storage conditions including duration of storage, type of storage container, and storage solution (plasma or an additive solution). Different in vivo and in vitro techniques can be used to analyse PCs. Platelets can be collected by apheresis technique, and from whole blood using either the buffy-coat or the platelet-rich plasma method. PCs can be gamma irradiated to prevent occurrence of graft-versus-host disease in the recipient. Pathogen inactivation procedures have been developed to prevent transmission of bacteraemia.

A feeder-free and efficient production of functional neutrophils from human embryonic stem cells

A novel, feeder-free hematopoietic differentiation protocol was established for highly efficient production of neutrophils from human embryonic stem cells (hESCs). For the induction of differentiation, spheres were generated in the presence of serum and cytokine cocktail and subjected to attachment culture on gelatin-coated plates. After approximately 2 weeks, a sac-like structure filled with abundant round cells emerged at the center of flattened spheres. After cutting off this sac-like structure, round cells actively proliferated, either floating in the supernatant or associated weakly with the adherent cells. Almost all of these round cells were CD45-positive hematopoietic cells with myeloid phagocytic markers (CD33 and CD11b), and approximately 30%-50% of the round cells were mature neutrophils, as judged from morphology, cytochemical characteristics (myeloperoxidase and neutrophil alkaline phosphatase), and neutrophil-specific cell surface markers (CD66b, CD16b, and GPI-80). In addition, hESC-derived neutrophils had chemotactic capacity in response to the bacterial chemotactic peptide formyl-methionyl-leucyl-phenylalanine and neutrophil-specific chemokine interleukin (IL)-8. Using "semipurified" neutrophils migrated to IL-8, both phagocytic and respiratory burst activities were demonstrated. Finally, it was shown that hESC-derived neutrophils had chemotactic activity in vivo in a murine air-pouch inflammatory model. The present results indicate successful induction of functional mature neutrophils from hESCs via highly efficient feeder-free differentiation culture system of human hematopoietic cells.

Successful autologous peripheral blood stem cell transplantation in a Jehovah's Witness with multiple myeloma: review of literature and recommendations for high-dose chemotherapy without support of allogeneic blood products

We present a case report of a successful high-dose melphalan therapy and autologous stem cell transplantation without the use of allogeneic blood product support in a 70-year-old patient suffering from multiple myeloma. Based on the experience in this case and thorough evaluation of the literature, we consider pre-transplant Hb level of 11-12 g/dl, platelet count higher than 70/nl, good WHO performance status of two and lower and informed consent as important eligibility criteria. During cytopenia recommended supportive measures include growth factor support with erythropoietin and G-CSF, p.o. iron treatment as well as prophylactic use of anti-fibrinloytic agents. Furthermore we discuss additional options that might be considered depending on the individual factors as e.g. pre-transplant collection and cryoconservation of autologous platelet concentrates. Moreover, an analysis of socio-economic issues regarding this procedure is presented. We conclude that allogeneic blood product free transplantation is a feasible procedure that can be offered to the patients belonging to distinct religious groups refusing allogeneic blood products as Jehovás Witnesses and patients presenting other contraindications for transfusions.

The quality of platelet concentrates produced by COBE Spectra and Trima Accel cell separators during storage for 7 days as assessed by in vitro methods

BACKGROUND

The quality of platelet (PLT) concentrates (PCs) can be evaluated with various in vitro methods. A new technique, free oscillation rheometry (FOR), can be used to monitor coagulation properties of PCs and gives information on clotting time and coagulum elasticity. This study compared the quality of apheresis PCs produced by the COBE Spectra and Trima Accel cell separators (both Gambro BCT) during storage for 7 days with in vitro tests including FOR.

STUDY DESIGN AND METHODS

Apheresis PCs were collected with the COBE Spectra (n = 10) and Trima Accel (n = 10) cell separators. Swirling, blood gases, and metabolic variables were analyzed on Day 0. Samples taken on Days 1, 5, and 7 were also analyzed for hypotonic shock response (HSR), P-selectin, and glycoprotein (GP)Ib expression and evaluation of coagulation by FOR.

RESULTS

Swirling, HSR, and percent GPIb-expressing PLTs were well maintained for 7 days, whereas glucose decreased and lactate increased significantly during storage for both Spectra and Trima PCs. Percent P-selectin-expressing cells increased to the same extent in both types of PCs during storage. pH increased between Day 0 and Day 1 but then decreased. The clotting time remained constant throughout the storage period whereas the development of elasticity was reduced on Days 5 and 7 compared to Day 1 (p < 0.05) for both types of PCs.

CONCLUSION

The results indicate that the PLT quality after storage for 7 days is well preserved, although activation of PLTs occurs during storage as assessed by in vitro tests. No difference in PLT quality was observed between Spectra- and Trima-produced PCs.

Hematomas in multicomponent apheresis: searching for related factors

BACKGROUND

The objective of this study was to identify donation variables that could be related to the development of hematoma during multicomponent apheresis collections (MACs).

STUDY DESIGN AND METHODS

This is an observational retrospective study where 1375 donors donated 5177 MACs during a 2-year period with two different machines (Amicus Crescendo [AC], Baxter Healthcare Corp.; and Trima Accel [TA], Gambro BCT). Variable data were recorded prospectively. In the multiple logistic regression analysis, generalized estimating equations were used with an exchangeable correlation matrix to take into account the nonindependence of several measurements from the same donor.

RESULTS

During the study period, 170 procedures failed due to hematoma (3.3%). Several variables were related to hematoma development in the adjusted model: operator experience (less than 500 procedures supervised vs. more; odds ratio [OR], 1.66; 95% confidence interval [CI], 1.19-2.31), previous apheresis donations (first time vs. more than 16 donations; OR, 2.87; 95% CI, 1.52-5.45), vein canalized (basilic vs. intermediate antebrachial or cephalic; OR, 1.42; 95% CI, 1.04-1.94), diastolic blood pressure (units divided by 10 mmHg; OR, 0.79; 95% CI, 0.66-0.94), and type of machine used (TA high return limit configuration [RLC] setting configuration vs. AC; OR, 1.94; 95% CI, 1.27-2.96; TA low RLC setting configuration vs. AC; OR, 1.24; 95% CI, 0.83-1.84).

CONCLUSIONS

Our study suggests that hematoma in MAC is not a random event. Appropriate machine configuration in the TA could reduce the hematoma rate to a level comparable with that of the AC. Operator training and donor blood pressure are also interesting variables for study because these could be modified to reduce the hematoma rate.