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Background and Objectives Leukapheresis has become a standard practice to collect CD34+ haematopoietic progenitor cells (HPC) from peripheral blood. Hypocalcemic toxicity (hypocalcaemia) is the most common complication during leukapheresis associated with citrate-based anticoagulation (AC) infusion. This report describes a new approach to limit citrate exposure by increasing the inlet:AC ratio while maintaining original inlet flow rates on the device in order to decrease the AC infusion rate. Materials and Methods A retrospective analysis was performed on 63 autologous and 29 allogeneic HPC collections. Procedures were started at a conservative inlet:AC ratio of 12:1 with gradual ratio ramping (RR) during the procedure, or at an inlet:AC ratio of 13:1 or higher (HIR), with constant inlet flow rates. The clinical decision to change the ratio was based on platelet counts and concomitant medications, such as systemic anticoagulants. Symptoms of citrate toxicity were treated by calcium supplementation. Results Customization of AC management with RR or HIR was performed in 91 of 92 procedures with a final inlet:AC ratio of 13:1-20:1, under careful supervision for platelet clumping episodes. Notably, 33 procedures were completed in individuals chronically treated with aspirin and/or warfarin. Citrate infusion gradually decreased with higher inlet:AC ratios, without affecting procedure time. The HIR strategy resulted in significantly smaller AC infusion volumes compared to RR, and lower frequency of calcium administration. CD34+ collection efficiency was not influenced by increasing inlet:AC ratios. Conclusion Customization of the inlet:AC ratio while maintaining a constant, stable inlet flow rate is effective in limiting citrate exposure during leukapheresis. [ABSTRACT FROM AUTHOR]

Background: Hyperleukocytosis is commonly seen in acute and chronic leukemias. Therapeutic leukocytapheresis using an automatic cell separator can help to achieve prompt leukoreduction to reduce the rate of thrombotic events and early mortality as well as to prevent tumor lysis syndrome., Aim: In this study, we report a single center's experience in managing leukemia patients with therapeutic leukocytapheresis prior to chemotherapy., Materials and Methods: Leukocytapheresis procedures were performed in 192 leukemia patients (including acute myeloid leukemia [AML], acute lymphoblastic leukemia [ALL], and chronic myeloid leukemia [CML]) with hyperleukocytosis between January and December 2016., Results: Median % reduction of white blood cell (WBC) count was 30.5% and median % removal efficiency was 46.7% for 75 procedures where the waste bag was sampled. WBC removal efficiency strongly depended on diagnosis (and was 71%, 66%, and 39% for ALL, AML, and CML, respectively). Procedures were generally well tolerated with only 9 out of 192 patients having mild adverse effects., Discussion and Conclusion: In the absence of specific guidelines for the management of hyperleukocytosis, leukocytapheresis in association with chemotherapy should be considered early in clinical practice., (© 2019 Wiley Periodicals, Inc.)

Background: As COBE Spectra has been replaced in many parts of the world, we describe a new protocol for low-density lipoprotein (LDL)-apheresis performed on familial hypercholesterolemia patients for the Spectra Optia platform., Methods: For all procedures, after administering a bolus of heparin of 2,500 U, 10,000 U of heparin added to a 600 ml ACD-A bag was used as anticoagulant (AC). In a first phase (A), 16 apheresis procedures with COBE Spectra using an inlet:AC ratio of 25:1 were compared to 18 LDL-apheresis treatments with Spectra Optia at split Inlet:AC ratios of 16:1/18:1 or 20:1/25:1. Platelet activation and coagulation markers were assessed. In a follow-up phase (B), 20 procedures on Spectra Optia using an inlet:AC ratio of 20:1 were performed., Results: Although coagulation markers and platelet activation analyzed were similar in both apheresis devices used, COBE Spectra procedures did not show any visual clumping in the sets. Visual analysis of clumping was highest in the Spectra Optia's 20:1/25:1 AC regimen (5/8 procedures). For the lowest Spectra Optia, AC regimen and during the follow-up phase reversible clump formation in the disposable set was similar (1/10 procedures). Clumping was successfully reversed in all cases by temporarily lowering the inlet:AC ratio to 18:1. Blood cell counts (WBC, Plt, Hct) were similar for both COBE Spectra and Spectra Optia procedures. Spectra Optia had a significantly higher plasma removal efficiency versus COBE Spectra (84% vs.75%, P < .05). No serious adverse events were observed., Conclusion: Apheresis procedures on the Spectra Optia system with low-dose heparin-citrate anticoagulation are feasible and safe., (© 2016 Wiley Periodicals, Inc.)

Background: Therapeutic plasma exchange (TPE) is either performed using a highly permeable filter with standard multifunctional renal replacement equipment (mTPE) or a centrifugation device (cTPE). Although both techniques are well established in clinical practice, performance of these two modes of TPE was never compared in a prospective randomized fashion. Thus we aimed to compare two commercially available therapeutic apheresis systems: mTPE (Octonova with Plasmaflo filter) and cTPE (Spectra Optia apheresis system)., Methods: Twenty-one patients (age 51.6 ± 13.5 years; 10 F/11 M; BMI 25.1 ± 5.0 kg/m(2)) were enrolled in this randomized, prospective, paired, crossover study performed in the Hannover Medical School, Germany. First treatment (either mTPE or cTPE) was chosen by an online randomization list. The primary endpoints were plasma removal efficiency with 1.2× of the total plasma volume exchanged. Secondary endpoints were total amount of plasma substances removed, such as IgG and fibrinogen. Further, the treatment effect on platelet count and complications were evaluated., Results: Despite a comparable volume of the processed plasma, mTPE treatment time was 10.5 % longer than cTPE treatment time (p < 0.05), resulting in a 10 % lower plasma removal rate of the mTPE treatment. Both treatments were comparable in terms of decrease in median (IQR) IgG [pre-mTPE 5.34 (3.48-8.37), post-mTPE 1.96 (1.43-2.84) g/L; pre-cTPE 5.88 (3.42-8.84), post-cTPE 1.89 (1.21-3.52) g/L]. Also the median (IQR) amount of IgG removed in mTPE [13.14 (7.42-16.10) g] was not different from the cTPE treatment [9.30 (6.26-15.69) g]. This was also true for IgM removal. Platelet loss during mTPE was nearly twice as much as with cTPE (15 ± 9 versus 7 ± 9 %, p < 0.05)., Conclusion: Although the centrifugal procedures were conducted using flow rates that could easily be obtained using peripheral access, plasma removal efficiency was significantly higher and treatment time was significantly lower in cTPE as compared to mTPE. Despite this lower treatment time, the decline in markers of procedure efficacy was comparable. Especially in centers performing many procedures per year, cTPE in contrast to mTPE can reduce treatment time without compromising treatment efficacy.

Background: This study evaluated the ability of a modified cell separator (Cobe Spectra Apheresis) system to isolate monocytes (MOs) by elutriation. The evaluation was performed in two independent international laboratories. The capacity of collected MOs to differentiate into dendritic cells (DCs) was also assessed., Study Design and Methods: MNCs from platelet apheresis residues were elutriated on a modified cell separator (Cobe Spectra Apheresis system) using a custom disposable set. Cells were separated according to their size and density. Recovery and purity of the collected cell product were evaluated by impedance counting and flow cytometry. DCs were differentiated in culture from the elutriated MOs and characterized by their surface markers and stimulatory capacity in a mixed WBC reaction assay., Results: Six apheresis mononuclear cell products were used by each laboratory. The separation was achieved in less than 1 hour. Collected MOs had the potential to differentiate into DCs., Conclusion: The modified cell separator is an easy and fast device to obtain highly enriched MOs with a DC differentiation potential. The system is closed and employs a single-use disposable set and is more amenable to good tissue practice. This method could become a valuable tool for DC-based active immunotherapy.

We assessed the in vivo effect of six intact anti-human antiplatelet antibodies of two major IgG subclasses on platelet kinetics in baboons. Five of the six antibodies tested caused thrombocytopenia of varying degree when injected at a precalculated threshold value. An agglutinating IgG1 antibody (MA-8L4A12) caused a long-lasting, mild thrombocytopenia with a predominant uptake of radiolabelled platelets in the spleen, while the four IgG2 antibodies tested (MA-13G8E1, MA-2M5A6, MA-21K2E8 and MA-22M10) caused a severe, transient thrombocytopenia with uptake of platelets in the liver. Two of the IgG2 antibodies (MA-13G8E1 and MA-2M5A6) caused platelet activation and aggregation in vitro, whilst the other two did not elicit a platelet aggregation response. The platelet survival time was shortened with all five of the thrombocytopenia-inducing antibodies, while only one antibody (MA-2M5A6) had a significant effect on the bleeding time. This study indicates that the IgG subclasss may be a determining factor in the outcome of platelet sequestration in immune-induced thrombocytopenia.