Blood component collection by apheresis

Apheresis component collection is a rapidly growing area in the blood collection field. Several instruments with varying capabilities are available. This is a brief review of the equipment available for granulocyte and apheresis component collection and indications for their use. In the United States, granulocytes are collected with the Fenwal CS3000, Fenwal CS3000 Plus, COBE (Gambro) Spectra, Haemonetics LN9000, and Fresenius AS 104. The use of hetastarch for sedimenting agent and stimulation with G-CSF and G-CSF plus dexamethasone have substantially increased granulocyte yields. Plateletapheresis is performed in the United States on the Fenwal CS3000, Fenwal CS3000 Plus, Fenwal Amicus, COBE (Gambro) Spectra, Gambro Trima Version 4, Gambro Trima Accel (Version 5), and Haemonetics LN9000. Automated red blood cell (RBC) collections are performed with the Haemonetics MCS+LN8150, Gambro Trima Version 4, Gambro Trima Accel (Version 5), Amicus, and Baxter Alyx. The RBC can be collected concurrently (with other components) in some instruments or separately in others. Plasma is collected concurrently on several instruments. Plasmapheresis for plasma only is performed on the Fenwal Autopheresis C and Haemonetics PCS2. Granulocyte yields range from 0.46 x 10(10) to 1.0 x 10(10) for unstimulated donors and 2.1 x 10(10) to 2.6 x 10(10) for donors stimulated with dexamethasone or prednisone. The use of G-CSF and G-CSF with dexamethasone has substantially increased granulocyte yields with yields of 4.1 x 10(10) to 10.8 x 10(10) reported. Platelet collection rates of 0.045-0.115 x 10(11) plt/min have been reported. Collection efficiencies of 46-85.7% have been reported. Automated (apheresis) component collection has the advantages of controlled volumes or doses of component, efficient use of the donor, multiple components from the same donor, better inventory control, and better quality control due to less manipulation of the individual components. Disadvantages of automated component collection include the use of expensive equipment and disposables, the need for specially trained machine operators, and lower capacity to collect large volumes of blood compared to whole blood donation. The use of apheresis component collection is rapidly growing to provide the best blood components in the most efficient manner.     

Red cell apheresis in autologous preoperative blood donation.

Preoperative autologous blood donation (PAD) is a commonly used technique for elective surgical procedures with a predictable blood loss. The conventional method is to collect one unit whole blood weekly several times within the shelf-life of red cell concentrates. Erythrapheresis with the Haemonetics cell separator MCS-3p or plus makes it possible to collect two units of red cells in one single session and with this option the time interval and operation can be prolonged to three weeks to improve erythropoiesis. 295 patients, who were scheduled for hip replacement or knee endoprothesis were evaluated retrospectively calculating the net profit of red cells after donating two units of red cells by erythrapheresis. The median net profit of red cells was 140 ml red cells but with a wide range. The patients who profit most of PAD were those with a predonation hct below 42% who had net profits up to 300 ml red cells due to an increased erythropoiesis, which compensate for the withdrawal of the red cells. Thus erythrapheresis with the Haemonetics MCS-3p or Haemonetics MCS plus is recommended for patients with a predonation hct lower than 42% and who can be scheduled for PAD at least 3 weeks before operation when two units of red cells are the target for PAD.     

Crude collection efficiency of CD34+ hematopoietic stem cell apheresis

Understanding the apheresis principles for harvesting hematopoietic stem cells (HSCs) is critical for performing efficient procedures. However, despite significant advances in estimating the collection efficiency (CE) of aphereses, many confounding factors still need to be addressed in the classical calculations. The CE values are unrestricted, and many procedures exhibit CEs of a given cell population greater than 100%. This report introduces a simple equation that estimates the “crude” CE, which ranges from 0% to 100% and intrinsically considers the contribution of donor-related variables such as the pre-procedure mobilization and intra-apheresis recruitment of CD34⁺ cells (as a convenient marker for HSCs), as well as the performance of the apheresis system itself.     

Red cell apheresis: new concepts of blood component processing.

Since red cell apheresis procedures were introduced in Europe, more than 6,000 automated blood component collections have been processed. Analyzed were results of different protocols (RBCPS, RBCP, SDP-RBC). Quality of blood components was measured over a storage period of 42 days (red cell concentrates) versus 5 days (platelet concentrates). Processing times were <8 min for RBCPS, <22 min for RBCP, and <90 min for SDP-RBC. All collected blood components fit the standards of the European guidelines. The results for red cell concentrate storage are as good as the results for manual collection (ATP, hemolysis parameters, glucose, lactose) or better (2,3-DPG, rheological parameters). Storage data of platelet concentrates are similar to platelet apheresis. All apheresed blood products are sterile after storage. Red cell apheresis procedures are a challenge for blood component processing and will encourage a revision of national blood and plasma programs for self-sufficiency.     

Implementation of concurrent red blood cell and platelet collection by apheresis in a university haemapheresis unit

The present study analyses the number of concurrently collected red blood cell (RBC) units in plateletpheresis donors and the reasons why donors were deferred from multicomponent collection. Donors undergoing concurrent collection of RBCs and platelets (PLTs) were retrospectively evaluated for haemoglobin values and the reasons for deferral over a period of 1 year. A total of 404 RBC units were concurrently collected with PLTs. An average of 1.8 RBC units per year was collected from each donor. The baseline haemoglobin values were almost equal for the RBC donations. An RBC unit was not collected in 190 aphereses. Most frequent reasons for the noncollection of an RBC product were a donation interval of less than 3 months (20.5%), haematoma and blood flow problems (18.9%) and low pre-haemoglobin values (17.4%). Donor eligibility has to be taken into account to optimize concurrent RBC collection in plateletpheresis.     

Comparison of two double red cell collection settings on Fenwal Alyx apheresis instrument

The Fenwal Alyx for collecting double red cell products has two red cell volume collection settings: fixed collection target of 360 ml (180 ml/unit) and a variable target of collecting either 400 or 360 ml (200 or 180 ml/unit), where the machine aims for the higher possible collection target. We retrospectively compared the two collection targets for the RBC content, donor time, technician time, and collection efficiency. We compared 18 fixed (F) target collections to 40 variable (V) target collections. All collections were performed as per the manufacturer's recommendations on Alyx and donors met the manufacturer's eligibility criteria. There was no significant difference in average whole blood processed (F: 963 ml, V: 1,000 ml); donor time (F: 43 min, V: 45 min) or technician time (F: 64 min, V: 64 min). There was a significant difference in unit volume (F: 283 ml, V: 300 ml); grams Hb/unit (F: 53 g, V: 57 g); ml RBC/unit (F: 157 ml, V: 167 ml); and RBC recovery (F: 87.8%, V: 88.9%). The fixed target had a significantly lower frequency of products with ≥51 g Hb (80.6%) than variable target (96.3%) and ≥153 ml RBC/unit (F: 55.6%, V: 96.3%). In conclusion, the variable target efficiently allows collections of products with higher red cell volume and hemoglobin without a significant increase in collection and processing time.     

Three-hour collection of committed and multipotent hematopoietic progenitor cells by apheresis

Although multipotent progenitor cells have been collected from blood in humans by apheresis in 1- to 2-hour collections, longer-term collections of multipotent progenitor cells have not been reported. To determine whether such collections could be sustained, the authors performed six 3-hour collections on five normal volunteers, processing a mean of 8024 ml of blood. Blood samples were taken at 0, 1.5, and 3 hours, and component samples were taken at 1.5 and 3 hours. Cell counts, differentials, and committed myeloid (CFU-GM), erythroid (BFU-E), and multipotent (CFU-MIX or CFU-GEMM) progenitor cell assays were performed. Collection efficiency for progenitor cells, the number of cells collected divided by the number in the blood processed, did not diminish significantly. The number collected in the second 1.5-hour period resembled the number collected during the first. Circulating numbers did not fall significantly during apheresis. Prolongation of apheresis collections may reliably increase the number of progenitor cells available for eventual hematopoietic reconstitution.     

Heparin-induced thrombocytopenia associated with collection of hematopoietic progenitor cells by apheresis

Heparin-induced thrombocytopenia (HIT) can occur following exposure to heparin and is characterized by thrombocytopenia with increased risk for thrombosis. This condition is mediated by formation of immunoglobulin G antibodies against platelet factor 4/heparin complexes that can subsequently lead to platelet activation. Herein, we detail the clinical and laboratory findings, treatments, and outcomes of two patients who developed HIT and thrombosis after undergoing collection of hematopoietic progenitor cells by apheresis (HPC-A) for autologous HPC transplant. Given that heparin may be used during HPC-A collections, these cases emphasize the importance of prompt consideration of HIT in patients that develop thrombocytopenia and thrombosis following HPC-A collection with heparin anticoagulation.     

Progenitor cell recruitment during individualized high-flow, very-large-volume apheresis for autologous transplantation improves collection efficiency

BACKGROUND: Individual adaptation of processed patient's blood volume (PBV) should reduce number and/or duration of autologous peripheral blood progenitor cell (PBPC) collections. STUDY DESIGN AND METHODS: The durations of leukapheresis procedures were adapted by means of an interim analysis of harvested CD34+ cells to obtain the intended yield of CD34+ within as few and/or short as possible leukapheresis procedures. Absolute efficiency (AE; CD34+/kg body weight) and relative efficiency (RE; total CD34+ yield of single apheresis/total number of preapheresis CD34+) were calculated, assuming an intraapheresis recruitment if RE was greater than 1, and a yield prediction models for adults was generated. RESULTS: A total of 196 adults required a total of 266 PBPC collections. The median AE was 7.99 x 10(6), and the median RE was 1.76. The prediction model for AE showed a satisfactory predictive value for preapheresis CD34+ only. The prediction model for RE also showed a low predictive value (R2 = 0.36). Twenty-eight children underwent 44 PBPC collections. The median AE was 12.13 x 10(6), and the median RE was 1.62. Major complications comprised bleeding episodes related to central venous catheters (n = 4) and severe thrombocytopenia of less than 10 x 10(9) per L (n = 16). CONCLUSION: A CD34+ interim analysis is a suitable tool for individual adaptation of the duration of leukapheresis. During leukapheresis, a substantial recruitment of CD34+ was observed, resulting in a RE of greater than 1 in more than 75 percent of patients. The upper limit of processed PBV showing an intraapheresis CD34+ recruitment is higher than in a standard large-volume leukapheresis. Therefore, a reduction of individually needed PBPC collections by means of a further escalation of the processed PBV seems possible.     

Kinetic studies during peripheral blood stem cell collection show CD34+ cell recruitment intra‐apheresis

A sufficient number of CD34+ cells in the peripheral blood stem cell product is important to achieve a rapid and sustained engraftment. The purpose of the present work was to study CD34+ cell kinetics during leukapheresis. Blood samples before and after leukapheresis were analysed for CD34+ cells in 205 procedures. The number of CD34+ cells after plus the number of CD34+ cells harvested was 1.5‐fold greater than the number available at the beginning of the procedure, indicating recruitment of CD34+ cells during leukapheresis. In a subgroup of 66 procedures, granulocytes and platelets were measured. In contrast to CD34+ cells, these cell fractions were not recruited to the blood stream during leukapheresis. An additional nine patients were studied with serial blood measurements during leukapheresis, showing an initial decline that was followed by an increase in CD34+ cells during leukapheresis. In conclusion, CD34+ cells are recruited to the blood during the leukapheresis procedure in contrast to granulocytes and platelets. J. Clin. Apheresis. 16:114–119, 2001. © 2001 Wiley‐Liss, Inc.     

In vitro variables of red blood cell components collected by apheresis and frozen 6 and 14 days after collection

BACKGROUND: An automated cell processing system (ACP 215, Haemonetics Corp.) can be used for the glycerolization and deglycerolization of RBC components, but the components must be 6 or fewer days old. Depending on the anticoagulant (CP2D)/additive solution (AS) used, deglycerolized RBCs can be stored at 1 to 6 degrees C for up to 14 days. This study evaluated in vitro variables of apheresis RBC stored for 6 and 14 days at 1 to 6 degrees C before glycerolization and 14 days after deglycerolization. STUDY DESIGN AND METHODS: Two units of CP2D/AS-3 leukoreduced RBCs were collected by apheresis from seven donors. One unit was glycerolized and frozen 6 days and the other 14 days after collection. All units were deglycerolized with the ACP 215 and stored at 1 to 6 degrees C for 14 days in AS-3. Several in vitro variables were evaluated during postdeglycerolization storage. RESULTS: All components had postdeglycerolization RBC recoveries greater than 81 percent and osmolalities of less than 400 mOsm per kg. No significant differences were noted in potassium and supernatant hemoglobin after 14 days of postdeglycerolization storage between RBCs frozen at 6 and 14 days after collection. After 14 days of postdeglycerolization storage, however, the pH, lactate, and ATP levels were slightly lower in RBCs frozen after 14 days. CONCLUSION: The ACP 215 can be used to glycerolize and deglycerolize apheresis RBC components that are up to 14 days of age. It is likely that apheresis components glycerolized at 14 days of age or less can be stored up to 14 days in AS-3 after deglycerolization, but this should be confirmed with in vivo survival studies.     

Automatic interface-controlled apheresis collection of stem/progenitor cells: results from an autologous donor validation trial of a novel stem cell apheresis device

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.     

Evaluation of an algorithm based on peripheral blood hematopoietic progenitor cell and CD34+ cell concentrations to optimize peripheral blood progenitor cell collection by apheresis

BACKGROUND: Quantification of peripheral blood (PB) CD34+ cells is commonly used to plan peripheral blood progenitor cell (PBPC) collection but is time-consuming. Sysmex has developed a hematology analyzer that can quickly identify a population of immature hematopoietic cells (HPCs) according to cell size, cell density, and differential lysis resistance, which may indicate the presence of PBPCs in PB. This prospective study has evaluated the potential of such method to predict the PBPC mobilization. STUDY DESIGN AND METHODS: A total of 141 patients underwent PBPC mobilization. PB HPCs and PB CD34+ cells were simultaneously quantified with a hematology analyzer (SE2100, Sysmex) and flow cytometry, respectively. The number of blood volumes processed was then based on PB CD34+ cell concentration. RESULTS: The optimal PB HPC level able to predict a minimal level of 10 x 10(6) PB CD34+ cells per L was 5 x 10(6) per L with positive and negative predictive values of 0.93 and 0.36 percent, respectively. For this cutoff point, sensitivity and specificity were 0.81 and 0.65, respectively. The median number of blood volumes processed according to the PB CD34+ cell count allowed us to perform only one apheresis procedure for a majority of patients. CONCLUSION: PB HPC quantification is very useful to quickly determine the initiation of PBPC apheresis especially for patients with higher concentrations. For patients exhibiting a lower HPC count (<5 x 10(6)/L), other parameters such as a CD34 test may be needed. Such a policy associated with a length of apheresis adapted to the richness in the PB CD34+ cells allows for optimizing the organization of centers with an improvement in patient comfort and economical savings.