Removal Of White Blood Cells Research Articles

Dynamics of white blood cell retention by white blood cell removal filters.

TransfusionVolume 44, Issue 9 p. 1271-1272 Dynamics of white blood cell retention by white blood cell removal filters Muttuswamy Sivakumaran, Corresponding Author Muttuswamy Sivakumaran From the Department of Haematology, Peterborough District Hospital, Peterborough, United Kingdom.Muttuswamy Sivakumaran, MSc, FRCP, FRCPath, PhD, Department of Haematology, Peterborough District Hospital, Thorpe Rd, Peterborough, United Kingdom; e-mail: m.sivakumaran@pbh-tr.nhs.uk.Search for more papers by this author Muttuswamy Sivakumaran, Corresponding Author Muttuswamy Sivakumaran From the Department of Haematology, Peterborough District Hospital, Peterborough, United Kingdom.Muttuswamy Sivakumaran, MSc, FRCP, FRCPath, PhD, Department of Haematology, Peterborough District Hospital, Thorpe Rd, Peterborough, United Kingdom; e-mail: m.sivakumaran@pbh-tr.nhs.uk.Search for more papers by this author First published: 17 August 2004 https://doi.org/10.1111/j.1537-2995.2004.04031.xCitations: 2 TRANSFUSION 2004;44:1271-1272. Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume44, Issue9September 2004Pages 1271-1272 RelatedInformation

Effectiveness of leucoreduction for removal of infectivity of transmissible spongiform encephalopathies from blood

In 1999, the UK implemented universal leucoreduction as a precaution against transmission of variant Creutzfeldt-Jakob disease by transfusion of domestic blood or red blood cells. We aimed to assess how effectively leucoreduction reduced infectivity of transmissible spongiform encephalopathies (TSEs) in blood. 450 mL of whole blood collected and pooled from scrapie-infected hamsters was leucoreduced with a commercial filter. Blood cell concentrations were quantified, and infectivity titres measured. Blood cell recovery and white blood cell removal complied with American Association of Blood Banks standards. Leucofiltration removed 42% (SD 12) of the total TSE infectivity in endogenously infected blood. Leucoreduction is necessary for the removal of white-cell-associated TSE infectivity from blood; however, it is not, by itself, sufficient to remove all blood-borne TSE infectivity.

One-step concentration of malarial parasite-infected red blood cells and removal of contaminating white blood cells

BackgroundIsolation of a concentrated, living preparation of malarial parasite-infected red blood cells (PRBCs) that have low contamination of white blood cells (WBCs) facilitates research on the molecular, biochemical and immunological aspects of malarial parasites. This is currently carried out by a two-step method, including the concentration of PRBCs using density gradient centrifugation through Percoll or Nycodenz, followed by the removal of host WBCs using a cellulose powder column or a commercially available filtration unit. These two-step methods can help isolate sufficient PRBCs, but they are laborious. In this study, a simplified one-step procedure that takes advantage of the difference between diamagnetic low-spin oxyhaemoglobin and paramagnetic haemozoin (haem polymer) was described. The paramagnetic polymer is deposited in the food vacuoles of the parasite, allowing the use of magnetic separation to efficiently and rapidly concentrate PRBCs while removing contaminating host WBCs.MethodsThe magnetic removal of WBCs using a commercial LD column (MACS) was evaluated as a new method for concentrating and purifying PRBCs. To compare this method with the two density gradient centrifugation methods using Percoll or Nycodenz, we analysed the quantities of enriched PRBCs and contaminating host WBCs as well as the viability of malarial parasites in the final preparations.ResultsThe quantity of PRBCs and the viability of malarial parasites in the isolated PRBCs were similar between magnetic and centrifugation methods. However, 90–99% of the contaminating WBCs were removed from the starting material using a magnetic column, whereas WBC content did not change using the Percoll or Nycodenz methods.ConclusionThe use of a commercially available magnetic LD column is effective, safe and easy for the one-step purification of PRBCs. This simple method does not affect the viability of malarial parasites.

A late increase in free radical activity post myocardial infarction.

Free radicals (FR) are a highly reactive chemical species which have been implicated in the pathogenesis of reperfusion injury. Experimental models of reperfusion injury have demonstrated that FR scavengers improve myocardial salvage and thus it has been postulated that they may be of benefit in acute myocardial infarct (MI) patients treated with thrombolysis. Previous studies of FR activity post MI have focused on the immediate post reperfusion period; the present study investigates FR activity in post MI patients over a longer time span. Free radicals have a very short half-life and in clinical studies their activity is usually assessed indirectly by measuring either the level of FR reaction products such as malondialdehyde (MDA) or FR scavengers such as plasma thiols (PSH). In the presence of increased FR activity MDA levels increase and PSH levels decrease. Twenty-two acute MI patients had blood samples taken on admission, day 7 and day 21 post MI for measurement of MDA and PSH levels. On day 7 post MI a significant increase in MDA was detected P = 0.0001 (Sign test) (median change +2.1 mumol.l) and a significant decrease was detected in PSH P = 0.04 (Sign test) (median change, -38 mumol.l-1). No significant differences were detected between admission and day 21 levels of MDA and PSH. This study demonstrates the presence of enhanced FR activity at a later time point than has previously been recognised. White blood cells utilise FRs during phagocytosis and the late rise in FR activity detected in this study may reflect white blood cell removal of necrotic myocardium.

The role of cytokines in blood transfusion reactions

Recent advance in the understanding of the mechanism of hemolytic transfusion reactions results from the investigation of cytokine generation in in vitro models of incompatible red blood cell transfusion. Cytokines with pyrogenic and pro-inflammatory activities as well as cytokines with activating properties for granulocytes, monocytes and endothelial cells are produced in both ‘intravascial’ and ‘extravascular’ types of hemolytic reactions. It has also been demonstrated that cytokines are generated and accumulated in blood components such as platelet concentrates, during storage. A large part of febrile transfusion reactions results from transfusion of stored platelet concentrates containing high cytokine levels and not from antigen-antibody reaction. Prestorage removal of white blood cells, which generate cytokines during storage, from platelet concentrates reduces strongly the reaction incidence and should be standard practice.

Transfusion-transmitted Yersinia enterocolitica infection. Protection through buffy coat removal and failure of the bacteria to grow in platelet-rich or platelet-poor plasma.

In a previous study, removal of white blood cells (WBC), by filtration 5 h after deliberate contamination of whole blood with a type 0:3 strain of Yersinia enterocolitica, was shown to be an effective way of avoiding bacterial growth in red blood cells (RBC) during storage. In the present study the Opti-System technique was used to remove the buffy coat from whole blood, leaving 10-20% of the original number of WBC in the RBC preparation. In one series of experiments, all of 4 units of RBC suspension, from which buffy coats were removed 2 h after inoculation of 112 colony-forming units (cfu) per ml of Y. enterocolitica, became Yersinia-free, while abundant bacterial growth occurred in all of 4 units where RBC suspension and buffy coat had been recombined. In a second series of 10 experiments, with an inoculum of 80 cfu/ml, no growth was found in platelet-poor plasma stored for 42 days at 4 degrees C. Five out of 10 RBC suspensions in SAGM additive solution remained Yersinia-free throughout a 6-week storage period; 4 of these 10 units showing growth of Yersinia after 4 weeks and 5 after 6 weeks. In the buffy coats bacterial growth was found in 1 out of 10 units after 1 week, 4 after 2 weeks, and in all of 10 units after 4 weeks. In 2 control experiments with WBC-reduced RBC inoculated with the same bacterial dose, growth started within 24 h and was abundant after 1 week.(ABSTRACT TRUNCATED AT 250 WORDS)

Plasma exchange, but not extracorporal recirculation nor removal of white blood cells, depresses plasma levels of IL-1 during severe gram-negative septicemia

The production and secretion of interleukin-1 (IL-1) is a persistent and important event during early gramnegative septicemia. To investigate whether interventions such as plasma exchange, leukapheresis and extracorporal recirculation of autologous blood affected the plasma IL-1 activity, an experimental porcine model of septicemia was employed. 42 anesthetized piglets were divided into three sets each of 14 animals, and observed for 10 h after a sublethal i.v. infusion of live E.coli bacteria. Two animals were studied simultaneously in each set. Starting 135 min after the bacterial infusion, one animal in each pair was submitted to either plasma exchange, extracorporal recirculation or removal of white blood cells (leukapheresis). Induction of septicemia produced a biphasic IL-1-response. A significant increase in IL-1 was seen peaking at 60 min, followed by a subsequent decrease. A second and more pronounced increase in IL-1 levels was seen 10 h after induction of septicemia in all animals, reaching a 100-fold increase compared to basal levels. Plasma exchange significantly lowered plasma IL-1 levels for 4 h after the exchange session. Neither extracorporal recirculation, nor leukapheresis significantly influenced IL-1 activity. A biphasic IL-1 release occurs during early gram-negative septicemia. It is possible to reduce these elevated IL-1 levels by plasma exchange, this is associated with improved cardiovascular status and prolonged survival.

Transfusion-Transmitted Yersinia enterocolitica Infection

In a previous study, removal of white blood cells (WBC), by filtration 5 h after deliberate contamination of whole blood with a type 0:3 strain of Yersinia enterocolitica, was shown to be an effective way of avoiding bacterial growth in red blood cells (RBC) during storage. In the present study the Opti-System technique was used to remove the buffy coat from whole blood, leaving 10- 20% of the original number of WBC in the RBC preparation. In one series of experiments, all of 4 units of RBC suspension, from which buffy coats were removed 2 h after inoculation of 112 colony-forming units (cfu) per ml of Y. enterocolitica, became Yersinia-iree, while abundant bacterial growth occurred in all of 4 units where RBC suspension and buffy coat had been recombined. In a second series of 10 experiments, with an inoculum of 80 cfu/ml, no growth was found in platelet-poor plasma stored for 42 days at 4°C. Five out of 10 RBC suspensions in SAGM additive solution remained Yersinia-free throughout a 6-week storage period; 4 of these 10 units showing growth of Yersinia after 4 weeks and 5 after 6 weeks. In the buffy coats bacterial growth was found in 1 out of 10 units after 1 week, 4 after 2 weeks, and in all of 10 units after 4 weeks. In 2 control experiments with WBC-reduced RBC inoculated with the same bacterial dose, growth started within 24 h and was abundant after 1 week. In platelet-rich plasma (PRP), prepared from 4 units of whole blood that had been inoculated with Y. enterocolitica (106 cfu/ml), no bacterial growth was found during 10 days of storage at 22°C. Also, after Y. enterocolitica inoculation (114 cfu/ml) directly into PRP, bacteria failed to grow. We conclude that removal of the buffy coat from whole blood that had been previously contaminated with a moderate inoculation of Y. enterocolitica partly protects the red cells from bacterial growth during storage. The risk of transmitting Y. enterocolitica with platelet-poor plasma, liquid stored at 4°C, seems minimal. This bacterial species shows very poor capacity to grow in PRP at 22 °C.

Therapeutic leukapheresis

For the majority of leukemic patients, leukapheresis represents emergency treatment aimed at reducing the number of white blood cells and producing an immediate improvement in the clinical picture. We have shown that leukapheresis procedures performed for the therapy of leukocytosis in 4 patients with acute leukemia (2 myelocytic; 1 lymphocytic; 1 monoblastic) resulted in marked reduction in the white blood cell count and a considerable reduction in symptomatology. Repeat removal of white blood cells applied in 20 instances for patients with chronic myelocytic leukemia also produced a significant decrease in the cell count and relief of symptoms such as sweating, malaise, and pain due to splenomegaly. In chronic lymphocytic leukemia (31 patients), intensive and frequent leukapheresis procedures were followed by a marked fall in white blood cell count, regression of splenomegaly/ lymphadenopathy and resolution of many symptoms and signs induced by the large number of cells.

A clinically applicable method for long-term salvage of postischemic skeletal muscle

The clinical significance and applicability of interventions aimed at reducing reperfussion injury in postischemic skeletal muscle remain unproven, since long-term muscle salvage has not been demonstrated by most treatment protocols that attenuate early reperfusion injury. We have shown that reperfusion of ischemic skeletal muscle results in an early and prolonged sequestration of white blood cells and activation of the alternative complement cascade. The purpose of this study was to determine if 40 minutes of reperfusion with blood depleted of white blood cells and complement proteins, followed by 2 days of normal perfusion, would reduce muscle necrosis after 5 hours of ischemia. The isolated paired canine gracilis muscle model was used. The treatment muscle was initially reperfused with arterial blood that had been spun, washed, passed through a leukocyte removal filter, and resuspended in hydroxyethyl starch (>99.9% removal of white blood cells and the complement proteins factor B and C4). The contralateral control muscle was subjected to unaltered reperfusion. Blood flow (ml/min/100 gm) was measured by timed collection of gracilis venous blood. Myeloperoxidase activity (absorbance at 655 nm/min/mg tissue protein) in muscle biopsies was used to monitor white blood cell sequestration. After 48 hours of reperfusion in vivo, necrosis was quantified by nitroblue tetrazolium staining. Initial reperfusion with white blood cell and complement depleted blood significantly reduced muscle necrosis (53% ± 3% vs 29% ± 8%, p < 0.0025, paired t test). Early blood flow was improved, (p = 0.0025, repeated measure-ANOVA), but subsequent white blood cell sequestration was not altered (p = 0.33, repeated measure-ANOVA). This suggests that a significant amount of white blood cell mediated injury occurs during the first 40 minutes of reperfusion. Preventing early complement activation and white blood cell mediated reperfusion injury is an intervention that is feasible during surgery and may result in clinically significant salvage of postischemic skeletal muscle.

A clinically applicable method for long-term salvage of postischemic skeletal muscle

The clinical significance and applicability of interventions aimed at reducing reperfusion injury in postischemic skeletal muscle remain unproven, since long-term muscle salvage has not been demonstrated by most treatment protocols that attenuate early reperfusion injury. We have shown that reperfusion of ischemic skeletal muscle results in an early and prolonged sequestration of white blood cells and activation of the alternative complement cascade. The purpose of this study was to determine if 40 minutes of reperfusion with blood depleted of white blood cells and complement proteins, followed by 2 days of normal perfusion, would reduce muscle necrosis after 5 hours of ischemia. The isolated paired canine gracilis muscle model was used. The treatment muscle was initially reperfused with arterial blood that had been spun, washed, passed through a leukocyte removal filter, and resuspended in hydroxyethyl starch (greater than 99.9% removal of white blood cells and the complement proteins factor B and C4). The contralateral control muscle was subjected to unaltered reperfusion. Blood flow (ml/min/100 gm) was measured by timed collection of gracilis venous blood. Myeloperoxidase activity (absorbance at 655 nm/min/mg tissue protein) in muscle biopsies was used to monitor white blood cell sequestration. After 48 hours of reperfusion in vivo, necrosis was quantified by nitroblue tetrazolium staining. Initial reperfusion with white blood cell and complement depleted blood significantly reduced muscle necrosis (53% +/- 3% vs 29% +/- 8%, p less than 0.0025, paired t test). Early blood flow was improved, (p = 0.0025, repeated measure-ANOVA), but subsequent white blood cell sequestration was not altered (p = 0.33, repeated measure-ANOVA). This suggests that a significant amount of white blood cell mediated injury occurs during the first 40 minutes of reperfusion. Preventing early complement activation and white blood cell mediated reperfusion injury is an intervention that is feasible during surgery and may result in clinically significant salvage of postischemic skeletal muscle.

Use of Imugard IG500 filters for preparation of leukocyte-poor blood for cancer patients.

In order to determine the efficiency of Imugard IG500 filters in producing leukocyte-poor blood (LPB), 109 units of red cell concentrates were processed using cold (4 degrees C) or room temperature saline solution without the application of pressure to the blood bag. The results obtained in terms of red blood cell recovery, white blood cell removal, residual white blood cells, and free hemoglobin in the supernatant of the filtered units are comparable to those processed with the IBM 2991. LPB processed without pressure application to the blood bag and room temperature saline solution can be rapidly, efficiently and safely prepared in any size blood bank/transfusion service. This technique is definitely cost-saving in terms of equipment, software, space and personnel training.

Use of Imugard IG 500 Filters for Preparation of Leukocyte-Poor Blood for Cancer Patients

In order to determine the efficiency of Imugard IG500 filters in producing leukocyte-poor blood (LPB), 109 units of red cell concentrates were processed using cold (4°C) or room temperature saline solution without the application of pressure to the blood bag. The results obtained in terms of red blood cell recovery, white blood cell removal, residual white blood cells, and free hemoglobin in the supernatant of the filtered units are comparable to those processed with the IBM 2991. LPB processed without pressure application to the blood bag and room temperature saline solution can be rapidly, efficiently and safely prepared in any size blood bank/transfusion service. This technique is definitely cost-saving in terms of equipment, software, space and personnel training.

An acid protease in human erythrocytes and its localization in the inner membrane.

The isolation of erythrocytes of high purity from human blood was achieved by a combination of the two well established methods cells in erythrocyte preparations of different purities was studied. The acid protease activity was recovered to a level comparable with the recovery of erythrocytes, while the neutral protease activity as detected by the release of acid-soluble peptides from hemoglobin or casein disappeared in proportion to the removal of white blood cells. An acid protease was solubilized from the membranes of the purified erythrocytes by the extraction with 1-butanol. The enzyme was active in a pH range from 2 to 4, and sensitive to pepstatin. It was named pH-3 protease after its pH optimum. Sealed ghosts with right-side-out membranes and inside-out vesicles with reverted membranes were prepared from the purified erythrocytes and compared with respect to pH-3 protease activity for its latency as well as its inactivation by tryptic digestion. The results obtained indicate that pH-3 protase is localized on the inner surface of erythrocyte membranes. The self-digestion experiments at pH 4 using the sealed ghosts showed higher availability to pH-3 protease of spectrin and IVa protein than the other membrane proteins, also suggesting the localization of an acid protease in the inner membranes of erythrocytes.

Optimal Leukocyte Removal from Refrigerated Blood with the IBM 2991 Blood Cell Processor

One hundred forty-six units of two to five-day-old refrigerated blood were washed with the IBM Blood Cell Processor. The ABO and Rh types of the units varied according to available inventory. This study was designed to select the best protocol from the 42 possible combinations utilizing the machine's variable red blood cell override (RCO). A one liter wash program was used. The two parameters selected for study were the per cent red blood cell recovery and the per cent white blood cell removal. The protocol of choice uses a RCO of four seconds in the first and second steps of the program. This protocol yields a washed unit with a mean red blood cell recovery of 82 per cent and a mean white cell removal of 93 per cent. Our studies indicate that the IBM Blood Cell Processor can be used to wash two to five day old refrigerated blood for the preparation of leukocyte-poor blood that would meet the Standards of the AABB.

Development and use of pediatric frozen red cell packs.

Repeated transfusion of small increments of blood are frequently required for the sick and premature newborn infant to correct endogenous hypovolemia and/or to replace blood obtained for laboratory monitoring purposes. Previously fresh group and type specific whole blood was used. To eliminate waste of fresh whole blood, maintain fresh red blood cell properties, eliminate the hazards of transfusing plasma and to provide a more efficient system, a pediatric frozen red cell pack (PFRCP) has been developed. Units of group O rr red blood cells are glycerolized using a high glycerol method. The glycerolized red blood cells are separated into three equal aliquots and frozen. When needed, the PFRCP are deglycerolized by a modified procedure using the IBM Cell Processor. During a six month period, 71 infants were given 153 separate transfusions of deglycerolized red blood cells using 102 PFRCP prepared from 34 units of red blood cells. Red blood cell recovery, hematocrit, white blood cell removal, residual glycerol, total protein, and supernatant hemoglobin levels were measured. Clinical response was followed and found to be excellent.

Pathogenesis of fever.

Pathogenesis of fever.