Apheresis

A method for the fractionation of plasma, allowing albumin, y-globulin, and fibrinogen to become available for clinical use, was developed during World War II (see also Fractionation, blood-plasma fractionation). A stainless steel blood cell separation bowl, developed in the early 1950s, was the earhest blood cell separator. A disposable polycarbonate version of the separation device, now known as the Haemonetics Latham bowl for its inventor, was first used to collect platelets from a blood donor in 1971. Another cell separation rotor was developed to faciUtate white cell collections. This donut-shaped rotor has evolved to the advanced separation chamber of the COBE Spectra apheresis machine. 

Blood components are also collected through apheresis. In apheresis, advanced blood cell separators are used to collect one or more specific blood components from a donor. The cell separators collect blood iato a separation chamber, isolate the desired blood components, and return the blood components not needed to the donor. This procedure is performed on-line within one sterile disposable tubiag set. The two principal components collected through apheresis are plasma and siagle-donor platelets (SDP). 

Primary blood components iaclude plasma, red blood cells (erythrocytes), white blood cells (leukocytes), platelets (thrombocytes), and stem cells. Plasma consists of water dissolved proteias, ie, fibrinogen, albumins, and globulins coagulation factors and nutrients. The principal plasma-derived blood products are siagle-donor plasma (SDP), produced by sedimentation from whole blood donations fresh frozen plasma (FFP), collected both by apheresis and from whole blood collections cryoprecipitate, produced by cryoprecipitation of FFP albumin, collected through apheresis and coagulation factors, produced by fractionation from FFP and by apheresis (see Fractionation, blood-plasma fractionation). 

Transfusion-induced autoimmune disease has been a significant complication in the treatment of patients who require multiple platelet transfusions. Platelets and lymphocytes carry their own blood group system, ie, the human leukocyte antigen (HLA) system, and it can be difficult to find an HLA matched donor. A mismatched platelet transfusion does not induce immediate adverse reactions, but may cause the patient to become refractory to the HLA type of the transfused platelets. The next time platelets with an HLA type similar to that of the transfused platelets are transfused, they are rejected by the patient and thus have no clinical efficacy. Exposure to platelets originating from different donors is minimized by the use of apheresis platelets. One transfusable dose (unit) of apheresis platelets contains 3-5 x 10 platelets. An equal dose of platelets from whole blood donation requires platelets from six to eight units of whole blood. Furthermore, platelets can be donated every 10 days, versus 10 weeks for whole blood donations. 

The two principal appHcations of countercurrent flow are found in the Beckman elutriators and the Haemonetics apheresis equipment. The Beckman elutriators are capable of very specific cell separation of small batches of cells. The Haemonetics surge technique can separate platelets and lymphocytes from four Hters of donor blood in one hour and forty minutes. 

A small (25-kg), portable apheresis system, available in 1993, is designed to meet a wide variety of blood cell separation needs. The role of the apheresis system is to control the behavior, separation, and collection of blood components from the bowl while maintaining maximum donor safety. The system controls the flow rates of blood and components through variable pump speeds. It directs the flow of components out of the bowl, by fully automatic opening and closing of valves based on the output of the system sensors. The system monitors the separation of blood components in the bowl by an optics system that aims at the shoulder of the bowl. A sensor on the effluent line monitors the flow of components out of the bowl. 

Filtration Filtration (qv) is appHed in blood cell separation to remove leukocytes from ted blood cell (RBC) and platelet concentrates. Centtifugational blood cell separators do not reduce white blood cells (WBC) in red cell and platelet products sufficiently to avoid clinical complications such as GvHD and alloimmunization. A post-apheresis filtration step is needed to further reduce the WBC load. Modem filters are capable of a 3-log reduction in white cell contamination of the blood product, eg, apheresis single-donor platelet units having a typical white cell contamination of 5 x 10 white cells in 4 x 10 platelets can be reduced to a 5 x 10 white cell contamination, a sufficiently low number to avoid severe transfusion reactions. 

Leuko-reduction can be performed at the time of collection by apheresis in the blood lab or at the patient s bedside. Economic, quaUty assurance. 

R10. Ritter, M. M., Siihler, K., Richter, W., and Schwandt, P., Short and long-term effects of LDL-apheresis on lipoprotein (a) serum levels. Clin. Chim. Acta 195, 9-16 (1990). 

Scheding S, Ersoez 1, Hartmann U et al. Peripheral blood telomere length measurements indicate that hematopoietic stem cell turnover is not significantly increased in whole blood and apheresis platelets donors. Transfusion 2003 43 1089 1095. 

Homozygous familial hypercholesterolemia - 10 to 80 mg/day. Use atorvastatin as an adjunct to other lipid-lowering treatments (eg, LDL apheresis) in these patients or if such treatments are unavailable. 

Therapy, to provide the missing cells is possible in three ways. Leukocyte transfusions were, for a long time, employed but fell into disfavour. However, with the availability of stimulatory peptides it is quite practical to harvest large numbers from donors by apheresis technology so that this approach is re-emerging, particularly, in children. Lithium carbonate is of value in some patients although generally of doubtful benefit. In recent years the molecules... 

Wood L, Jogessar V, Ward P, Jacobs P. Estimation and predictive use of the corrected count increment -a proposed clinical guideline. Transfus Apheresis Sci 2005 32 117-24. 

Antihistamines may be given for the first few days of therapy to limit allergic reactions, and corticosteroids should be started and doses of diethylcarbamazine lowered or interrupted if severe reactions occur. Cures may require several courses of treatment. For patients with high L loa worm burdens (more than 2500 circulating parasites/mL), strategies to decrease risks of severe toxicity include apheresis, if available, to remove microfilariae before treatment with diethylcarbamazine or therapy with albendazole, which is slower acting and better tolerated, before therapy with diethylcarbamazine or ivermectin. 

Blood apheresis - [FRACTIONATION,BLOOD - CELL SEPARATION] (Vol 11)... 

Atorvastatin calcium is used as an adjunct to diet to reduce the elevated total-cholesterol, LDL, apolipoprotein B (apo B), and triglyceride (TG) levels, and to increase the HDL-C level in patients with primary hypercholesterolemia and mixed dyslipidemia. The drug is also used for the treatment of patients with an elevated serum TG levels, and for the patients with primary dysbetaliproteinemia, which do not respond adequately to diet. Atorvastatin calcium is also indicated to reduce the total-cholesterol and LDL-C in patients with homozygous familial hypercholesterolemia (e.g., LDL apheresis) [6]. 

Recombinant thrombopoietin is still an investigational agent. The primary focus of current clinical trials is for the treatment of chemotherapy-induced thrombocytopenia and thrombocytopenia accompanying hematologic stem cell transplantation. Other trials are looking into the possibility of administering thrombopoietin to normal donors in order to increase the number of cells recovered by platelet apheresis. Approval of the latter application will require that thrombopoietin be shown to have an excellent short- and long-term safety profile. 

Extracorporeal immunoabsorption of plasma over columns containing an inert silica matrix and covalently attached highly purified staphylococcal protein A (Prosorba column) involves apheresis of about 1200 mL plasma weekly for 3 months. 

Today all blood for transfusion is collected in plastic bags, and most of the plasma is immediately separated by the collector. In addition, source plasma collected by apheresis as a licensed product provides approximately 80% of the U.S. plasma supply [12]. The FDA still permits unlicensed recovered plasma without FDA-defined specifications to move interstate under short supply, however. This solution to the supply dilemma requires the final product manufacturers to assume the responsibility for assuring that their source materials are appropriate and effective in their manufacturing process. 

Suzuki, K., The role of immunoadsorption using dextran-sulfate cellulose columns in the treatment of systemic lupus erythematosus. Ther. Apheresis 4, 239-243 (2000). 

Wl. Wallace, D. J., Goldfinger, D., Pepkowitz, S. H., Fichman, M., Metzger, A. L., and Schroeder, J. O., Randomized controlled trial of pulse/synchronization cyclophosphamide/apheresis for proliferative lupus nephritis. J. Clin. Apheresis 13, 163-166 (1998). 

Tamai O, Matsuoka H, Itabe H, Wada Y Kohno K, Imaizumi T. Single LDL apheresis improves endothelium-dependent vasodilatation in hypercholesterolemic humans. Circulation 1997 95 76-82. 

The need to transfuse blood components such as plasma, platelets, factor VIII, in addition to red blood cells (RBC) has generated the development of plasmapheresis (plasma separation from whole blood) and more generally that of apheresis (fractionation of blood components). Plasma collection from donors by centrifugation of blood bags began only in 1944. This technique was extended to therapeutic plasma purification in 1950, but RBCs were fragilized by the centrifugation and the plasma was not completely platelet-free. 

Citrate phosphate Double dextrose/additive solution 3 Anticoagulant citrate phosphate 2X dextrose solution (CP2D) Use only with automated apheresis devices for collecting human blood and blood components 000127 Haemonetics Corp. 400 Wood Road Braintree, MA 02184 January 18, 2002... 

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