Apheresis Methods Research Articles

Storage of platelets in additive solutions: a multicentre study of the in vitro effects of potassium and magnesium.

In a preliminary study, the presence of potassium and magnesium in a modified synthetic medium (PAS-III) was found to have a significant influence on platelet metabolism (using apheresis-derived, as well as buffy-coat-derived platelets) when compared with standard PAS-III. The differences included reduced glycolysis, as evidenced by lower consumption of glucose and lower production of lactate, but also better preservation of pH and hypotonic shock response reactivity. The results suggested that storage in modified PAS-III containing 20% plasma was comparable to storage in standard PAS-III containing 30% plasma. To confirm the preliminary results and to evaluate the effects of different preparation protocols, an international multicentre study, which included 11 different sites, was conducted. Platelets from 30 pools of approximately 20 buffy coat (BC) units each and 24 pooled apheresis platelet units were aliquoted for storage in plasma (reference) or synthetic medium using either a specific additive solution (PAS-III) containing 30% plasma or a modification of PAS-III containing 5.0 mm potassium and 1.5 mm magnesium (PAS-IIIM) and either 30% or 20% plasma. Units were stored at room temperature with agitation for 7 days during which in vitro testing was carried out for biochemical, haematological and functional parameters. Storage of platelets in PAS-IIIM resulted in a reduction in the rate of glycolysis and better retention of pH and hypotonic shock response reactivity. Storage in PAS-IIIM containing 20% plasma appeared to result in the retention of in vitro properties, similar to those observed during storage in standard PAS-III containing 30% plasma. The results of this study confirm the preliminary results. Similar results were seen with platelets prepared by BC and apheresis methods, despite differences in equipment, the preparation technique and in the final platelet contents achieved in the platelet units. Storage of platelets in PAS-IIIM should be considered to improve platelet function and allow plasma reduction to 20%.

Cytokine levels as performance indicators for white blood cell reduction of platelet concentrates.

With the implementation of universal white blood cell (WBC) reduction in the UK, in-process WBC-reduction filters for pooled buffy coat (BC)-derived platelet concentrates (PCs) and apheresis methods are used routinely for the production of WBC-reduced PCs. While these strategies meet the specification for WBC reduction (< 5 x 10(6) WBCs/unit), the products from these processes may differ depending on the process employed and its performance. The aim of this study was therefore to investigate whether PCs prepared using various WBC-reduction processes are sufficiently depleted of WBCs to limit cytokine accumulation during storage and to assess if cytokine levels detected in platelet products can serve as indicators of acceptable platelet activation as a result of the WBC-reduction process. We measured the levels of cytokines predominantly derived from WBCs [e.g. interleukin-8 (IL-8)] and platelets [e.g. regulated on activation, normal, T-cell expressed, and secreted (RANTES) and transforming growth factor-beta(1) (TGF-beta(1))] under the present experimental conditions in different WBC-reduced PCs, i.e. PCs prepared from three different WBC-reduction filters and control non-filtered PCs using pooled BCs from the same donors and three apheresis types. Supernatant plasma was collected at the beginning (day 1) and end (day 5) of the shelf life of each PC, and the cytokine content was determined using appropriate enzyme-linked immunosorbent assays (ELISAs). Process efficiency was assessed by platelet yield and residual WBC count. We found that products from the apheresis process involving a filtration step (Haemonetics MCS+) showed a lower cytokine content on both day 1 and day 5 in comparison with the fluidized bed (COBE Spectra) or elutriation (Amicus) processes. WBC reduction of BC-PCs of the same origin using three different filters showed comparable levels of cytokines on day 1 in all units. After storage for 5 days, the levels of IL-8 remained essentially unchanged in filtered BC-PCs but increased by more than threefold in control non-filtered BC-PCs, suggesting IL-8 release by residual WBCs present in the control PCs. The concentration of platelet-derived cytokines such as RANTES and TGF-beta(1), however, increased significantly in all filtered and control non-filtered PCs during the storage period. These results show that markers of cytokine release from both WBCs and platelets are useful indicators of the performance and efficacy of the WBC-reduction process and of platelet quality.

The current status of therapeutic apheresis devices in the United States.

Over the last 40 years, plasmapheresis technology and its indications for use have been continually evolving. With the growing incidence for autoimmune diseases, unsatisfactory therapeutic options, side effects of drug therapy, and economic relevance, apheresis clinicians have been leaning toward more selective plasmapheresis techniques through the use of plasma fractionators and immunoadsorption columns. Plasma fractionators are mostly used in Asia, and rarely utilized in the U.S. The majority of plasma filters approved by the Food and Drug Administration (FDA) are primary membrane plasma separators, which still require replacement fluid. The secondary plasma fractionators available in the U.S. are limited in used and mostly investigational. Immunoadsorption columns, mostly used in Europe, are gaining popularity in the U.S. Some FDA-approved immunoadsorption columns include the Prosorba protein-A silica column, Immunosorba tryptophan and phenylalanine columns, Immunosorba protein-A sepharose column, and Liposorber dextran sulfate column. In addition, the heparin-induce extracorporeal lipoprotein precipitation (HELP) system is also FDA-approved. However, there are other immunoadsorption technologies used in Europe, such as direct adsorption lipoprotein LDL-hemoperfusion, not yet available in the U.S. While each method of apheresis carries its own risks and benefits, it is the opinion of the authors that these additional apheresis techniques be available to U.S. researchers and clinicians as a therapeutic option. The authors believe that the U.S. need to aggressively investigate more specific plasmapheresis modalities and establish appropriate dialogue with regulatory and reimbursement officials for FDA-approval of these devices.

Novel treatment modalities: new platelet preparations and substitutes.

Keywords: platelets; platelet substitutes; platelet haemostatic function; blood substitutes; platelet function

Large volume apheresis of autologous plasma and preparation of autologous fibrin glue from the plasma.

Autologous blood transfusion (ABT) is useful for prevention of undesirable effects of allogeneic blood transfusion. In our hospital, not only autologous whole blood but also autologous red blood cells, autologous fresh frozen plasma (Auto-FFP), and autologous fibrin glue (Auto-FG) are routinely produced for surgical patients. The Auto-FG is prepared from plasma which is separated from manually collected whole blood. However, when a large volume of Auto-FG is required, the plasma obtained by an apheresis method may be useful. Therefore, a pilot study was conducted to determine whether a collection of 2 U (160 ml) of red blood cells (RBCs) and 400 ml of plasma at 1 apheresis is acceptable. We first performed the apheresis on healthy donors, and then applied for autologous blood donation. The apheresis is safe. The collected plasma is used for the production of Auto-FFP and Auto-FG. The remaining RBCs also are used for ABT. The preparation of Auto-FG is simple, and it is effective for the reduction of allogeneic fibrin glue.

Recent advances of therapeutic apheresis in Guillain-Barré syndrome.

Acute idiopathic demyelinating polyneuritis (AIDP), commonly known as the Guillain-Barré syndrome (GBS), is an immune-mediated demyelinating disease of the peripheral nerve and nerve roots. A number of immunological mechanisms were described, but the exact pathomechanism has not been explained fully. Presumably, a variety of immunological processes lead to a relatively uniform clinical phenotype. Two large multicenter studies showed that plasma exchange (PE) was significantly superior to supportive treatment only. Selective adsorption (SA) also was employed as a method of therapeutic apheresis, and various smaller studies established that both PE and SA are equally effective treatments for GBS. Recently, it was demonstrated that the number of apheresis treatments should be adapted to the severity of disease. A large multicenter controlled study established equal efficacy of PE and intravenous immunoglobulin treatment (IVIg) as well as the combination of PE and IVIg. Since that time, the use of apheresis for the treatment of GBS declined in many countries due to the easier application of IVIg. The number of patients treated in larger hospitals with long-standing experience in the treatment of GBS also has declined.

Intraindividual Comparison of the Impact of two Selective Apheresis Methods (DALI and HELP) on the Coagulation System

We performed an intraindividual comparison of the effect on the coagulation system of two selective apheresis procedures: Direct Adsorption of Lipoproteins (DALI) and Heparin-induced Lipoprotein Fibrinogen Precipitation (HELP). Six patients suffering from heterozygous familial hypercholesterolemia have been treated with 2 sessions of each procedure. Anticoagulation was carried out according to usual recommendations. Blood samples were taken before, immediately after and on the second day after the sessions. We assessed global coagulation tests (prothrombin time, activated partial thromboplastin time), fibrinogen, prothrombin fragment F 1 + 2 and a variety of factors (Factors II, V, VII, XIII, IX, X, XI, XII, XIIa; von Willebrand Factor; collagen-binding activity, prekallikrein, high-molecular weight kininogen) and antagonists (antithrombin III, protein S activity, free protein S). In fact, all parameters measured have been influenced by the apheresis treatment. Fibrinogen is lowered more by HELP which also has a more definite impact on factors belonging to the prothrombin complex (II, VII, X). In contrast, the major effects of the DALI system have been seen on the intrinsic pathway of the coagulation system (IX, XI, prekallikrein, high-molecular-weight kininogen). With both systems, no increases in activated Factor XII or in prothrombin fragment F 1 + 2 have been observed. These data provide a solid basis for individual adaptations of anticoagulant doses.

A Successful and Simplified Filgrastim Primed Single Apheresis Method Without Large Volume Apheresis for Peripheral Blood Stem Cell Collection

There is a tendency to use only one apheresis collection to reduce the morbidity and the cost of peripheral blood stem cell collection. We studied whether rapid and complete engraftment could be achieved by single apheresis by using only Filgrastim without large volume apheresis in previously treated patients. Engraftment of single apheresis in 25 patients was compared with those of multiple apheresis in 26 patients; 52% of patients in the single apheresis group and 62% of patients in the multiple apheresis group were heavily pretreated. All patients received 10-15 microg/kg/day of Filgrastim starting on day 14 after 3-4 cycles of induction chemotherapy. Apheresis was performed using Cobe Spectra on day 4, 5 or 6 in the single apheresis group and every other day in the multiple apheresis group after day 3. The median collection volume was 250 ml (250-300 ml) in the single apheresis group and 750 ml (200-1500 ml) in the multiple apheresis group. The median CD34(+) cell number was not significantly different in the two groups (11.79 vs. 9.38x10(6)/kg). The median times to achieve leukocytes > or =1x10(9)/l and platelets > or =50x10(9)/l counts were 10 days (8-21 days) and 15 days (9-38 days) in the single apheresis group vs 11 days (8-23 days) and 20 days (10-32 days) in the multiple apheresis group, respectively (p<0.05). Antibiotic use was less in the single apheresis group than the multiple apheresis group (9 vs. 12 days, p<0.05). Adequate numbers of peripheral stem cells were harvested by G-CSF in a single apheresis without large volume apheresis even in heavily pretreated patients. Rapid and complete engraftment occurred in all patients and it was faster in single than multiple apheresis.

Low density lipoprotein hemoperfusion by direct adsorption of lipoproteins from whole blood (DALI apheresis): clinical experience from a single center.

The elimination of low density lipoprotein (LDL) and lipoprotein (a) (Lp[a]) by conventional LDL apheresis techniques can only be achieved in a cell-free medium and thus requires the initial separation of plasma from the blood cells. The present paper describes the first LDL hemoperfusion system which is able to adsorb LDL and Lp(a) directly from whole blood. This simplifies the procedure substantially. The adsorber consists of polyacrylate ligands linked to a modified polyacrylamide matrix. These negatively charged polyacrylate ligands interact with the positively charged apoprotein B moiety of LDL and Lp(a), which results in selective adsorption of these lipoproteins onto the column. Three hypercholesterolemic patients suffering from overt atherosclerotic complications were treated weekly by direct adsorption of lipoproteins (DALI) (n = 20 sessions each). All patients were on the highest tolerated dose of cholesterol synthesis enzyme (CSE) inhibitors. About 1.3 patient blood volumes were treated per session. The anticoagulation was performed with acid citrate dextrose (ACD-A). The following acute reductions were achieved: LDL: 66%; Lp(a): 63%; and triglycerides: 29%. High density lipoprotein (HDL) (-13%) and fibrinogen (-16%) were not substantially reduced. The sessions were essentially uneventful. Due to a low ACD-A infusion rate, no hypocalcemic episodes were registered. One patient on enalapril was treated without complications when this angiotensin converting enzyme (ACE) inhibitor was withdrawn 2 days prior to apheresis. In summary, in our hands, DALI apheresis proved to be a simple, safe, and efficient method of lipid apheresis in hypercholesterolemic patients refractory to conservative lipid lowering therapy.

Extracorporeal Antibody Elimination in Neuroimmunological Diseases

Extracorporeal procedures for the elimination of autoantibodies are an important therapeutic option in various neuroimmunological diseases, especially those with neuromuscular involvement. Recent advances with the development of selective apheresis methods have given extracorporeal therapeutic procedures a new perspective. In this article, we review the therapeutic use of plasma exchange and immunoadsorption therapy in different neuroimmunological diseases.

Leukocyte-reduced blood products.

During the past 10 years, methods for blood component preparation have undergone considerable change. Refinements of traditional methodologies were necessary in response to demands for increasingly effective and safe platelet support for the intensive chemotherapy for patients with malignant disease, as well as a response to evidence of the immunological effects of whole blood or unmanipulated erythrocytes. At the center of the issue is concern for the consequences of transfusing contaminant leukocytes. Clearly, for all transfusions the lowest possible leukocyte content is desirable, and their removal should be as early as possible during storage. This review of recent journal articles focuses on reports of investigations of the effects of allogeneic leukocytes in blood transfusions. There is a sense of competition among the advocates for secondary elimination of leukocytes (by filtration) versus those favoring the approach of primary avoidance of leukocyte contamination (by centrifugation). As the following summaries indicate, the relative merits of leukocyte reduction by filtration, either before or after storage, versus leukocyte reduction by specialized apheresis methods remain undefined. The goal of a universal guideline for the use of leukocyte-reduced blood components is not yet achieved.

Two patients with acute Guillain-Barré syndrome treated with different apheresis methods.

We treated 2 patients with severe acute Guillain-Barré syndrome (GBS) with different apheresis methods. Sera from these patients in the acute phase contained a high titer of immunoglobulin (Ig)G anti-GM1 ganglioside antibody. One was a 57-year-old female treated with immunoadsorption (IA). IgG anti-GM1 antibody titer was reduced from 1:102,400 to 1:6,400 measured by ELISA after 1 month. However, her residual deficit was severe. The other patient was a 43-year-old male treated with plasma exchange (PE). IgG anti-GM1 antibody was reduced from 1:3,200 to 1:400 after 1 session of PE. After 1 month, he could walk independently. The better prognosis of the latter was possibly because of the patient's younger age and the plasma exchange that might have reduced such pathogenic factors as antiganglioside antibodies at the early stage of GBS.

The efficacy of plasmapheresis or leukocytapheresis for articular and extraarticular manifestations of rheumatoid arthritis.

The authors investigated the clinical effectiveness of plasmapheresis (PP) or leukocytapheresis (LP) in 21 patients with articular or extraarticular manifestations of rheumatoid arthritis (RA). Salt-amino acid coprecipitation (SAC) or double membrane filtration plasmapheresis (DFPP) were used as PP regimens, and a centrifugation method (CS-3000) and leukocyte removal filter (Cellsorba) were used as LP regimens. The results were as follows. The removal rate of plasma globulin was higher with SAC than with DFPP, and the removal rate of leukocyte was higher with Cellsorba than with CS-3000. Based on a comparison of the present apheresis methods for short-term therapy, the leukocyte removal regimen proved more effective than the PP regimen by DFPP. In patients with extraarticular manifestations of malignant rheumatoid arthritis (MRA), there were rapid and dramatic intractable skin ulcers, rheumatoid nodules, low serum levels of complements, and high levels of immune complex. Cellsorba was the more useful regimen in short-term apheresis therapy as compared with DFPP. In RA or MRA patients receiving the long-term PP or LP regimen obvious improvements in grasping power and C reactive protein (CRP) levels were observed. The PP or LP regimen continuation rate was 88, 79, and 54% at 3, 12, and 20 months, respectively.

5494592 Apheresis apparatus and method

5494592 Apheresis apparatus and method

5494592 Apheresis apparatus and method

5494592 Apheresis apparatus and method

Counterflow centrifugation apheresis for the collection of autologous peripheral blood stem cells from patients with malignancies: A comparison with a standard centrifugation apheresis procedure

Two apheresis methods used to collect hematopoietic stem cells from peripheral blood were compared in eight patients with a variety of malignancies. The standard lymphocyte collection method was alternated with the counterflow centrifugation or lymphocyte surge protocol. The number of clonogenic cells (CFU-GM and BFU-E), the red cell volume, and the number of mononuclear cells in each collection were assessed as well as the changes in circulating leukocytes, platelets, and blood hemoglobin produced by each apheresis procedure. There was no statistically significant difference found in the number of clonogenic cells collected with either method, but the number of mononuclear cells collected with the standard procedure was significantly higher (P = 0.001). The red cell volume collected with the standard procedure was significantly higher, (P = 0.0001), but corrected for the number of mononuclear cells the difference was not significant. The counterflow centrifugation apheresis produced significantly less thrombocytopenia (P = 0.005). The counterflow centrifugation apheresis procedure used collected fewer mononuclear cells than the standard procedure, however, with less red cell contamination but a comparable number of CFU-GM and BFU-E in four hour apheresis procedures. Each collection method resulted in a comparable amount of anaemia and leukopenia but the lymphocyte surge method produced less thrombocytopenia following the collection.

A new low density lipoprotein apheresis system using two dextran sulfate cellulose columns in an automated column regenerating unit (LDL continuous apheresis)

We describe a new low density lipoprotein (LDL) apheresis system using dextran sulfate cellulose column in an automated column regenerating unit (LDL continuous apheresis). Two columns containing 150 ml of dextran sulfate cellulose were used, and the whole extracorporeal circulation was about 400 ml in volume. After 600 ml of plasma was adsorbed into the first column, the second column was used as an adsorbent and meanwhile the first column was regenerated. Thus, the 2 columns were used alternately without losing the potency of the columns. As the apparatus was automatically controlled by a computerized unit, no extra manipulation is necessary compared with the conventional single-column method. By treating 4–5 liters of plasma, non-high density lipoprotein (HDL)-cholesterol levels decreased by 63–71%, and HDL-cholesterol levels remained unchanged. Thus, this new method of LDL apheresis can safely reduce LDL-cholesterol to any desired level and will be applicable for the treatment of child and adult familial hypercholesterolemic patients with severe coronary heart disease.

Comparison of Apheresis and Other Methods for Separation and Purification of Hemopoietic Stem Cells: Initial Experience with a Blood Buffy Coat Model for the use of Autologous Bone Marrow Transplantation

With an increasing number of bone marrow transplantations (BMT) being contemplated in leukemia and cancer patients, it is prudent for blood banks to develop a suitable program within their resources for harvesting, purifying and freezing bone marrow stem cells. In order to do this, initially a prototype has been developed involving buffy coat model (BC) using normal donor blood. Centrifugation, sedimentation and machine apheresis methods were separately evaluated leading to a combined and sequential handling procedure. Blood was passed through a cell separator resulting collection of BC with 90% reduction of the volume showing 80% recovery of total leucocytes and 87% yield of mononuclear cells. Following centrifugation the cells with DMSO were frozen in a controlled freezing system and stored in liquid nitrogen. After thawing 94% cells were recovered with 93% viability. The initial experience gained in the model system could be incorporated in autologous BMT program in patients but requires modifications for improved results; the latter will be described separately.