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PubMed2006

[Evaluation of two methods for counting residual white blood cells in thrombocytaphoresis concentrates].

To evaluate flow-cytometry and Nageotte method for counting residual WBC in thrombocytaphoresis concentrates, their accuracies were determined by dilution studies separately; the repeatability was determined by measuring the interassay coefficient of variation for 14 replicates of a sample with known leukocyte concentration. 102 samples of leukocyte-depleted thrombocytaphoresis concentrates were detected by the above mentioned two methods, and the results were compared each other. The results showed that no difference was observed between two methods over a range of leukocyte concentrations from 0.8 to 10 WBC/microl (P > 0.05). In conclusion, flow-cytometry and Nageotte methods can be used for quality control of WBC-reduced blood components.

Blood Component Transfusion↗
PubMed2006

Isolation of fetal nucleated red blood cell from maternal blood using immunomagnetic beads for prenatal diagnosis.

The immunomagnetic beads method for isolation of fetal nucleated red blood cells (FNRBCs) from peripheral blood of 78 pregnant women for prenatal diagnosis was developed. The study subjects were classified into 8-10 and 11-14 weeks of gestation (n = 39 each). Peripheral blood cells were divided into two for the FNRBCs isolation using two protocols, one with anti-CD45 depletion followed by anti-CD71 and anti-GPA monoclonal antibodies and another without CD45 depletion. The use of CD45 depletion gave a slightly higher number of sorted cells but not significantly different (p > 0.05). The percentage of CD71+ and GPA+ cells obtained from 8-10 weeks and 11-14 weeks of gestation was not different (p > 0.05). The sensitivity in determining the sorted FNRBCs for male fetal sex by PCR using 8-10 and 11-14 weeks of gestation was generally 50 and 69%, respectively. The method so developed is simple and cost effective and may thus be applied for prenatal diagnosis.

Antigens, CD↗
PubMed2006

Does the inactivation of leukocytes in blood transfusions during and following liver transplantation by gamma-irradiation have an impact on rejection and infection rate?

BACKGROUND: Leukocytes transmitted in blood products exert a variety of immunological side-effects. Experience with bone marrow transplant recipients has shown that these can be induced even by very few cells. In liver transplant recipients, who usually receive large amounts of blood products, the effects of transfused leukocytes with regards to the rates of rejection and infection have not yet been investigated. MATERIAL/METHODS: Twenty liver transplant recipients were prospectively randomized to receive blood products (red blood cells, thrombocytes, fresh frozen plasma) through a leukocyte depletion filter, either irradiated with 40 Gy or not irradiated (10 patients, respectively). During the observation period of 90 days, the incidences of infections and rejections were analyzed. In addition, liver function tests, markers of infection (C reactive protein, lipopolysaccharide binding protein), and subpopulations of lymphocytes (total cell count, CD4/CD8 ratio, CD8CD45RO) were determined. RESULTS: Only one episode of mild rejection occurred (irradiated group). Rates of persistent graft dysfunction and severe infections were similar in both groups. The same applied to liver function tests, parameters of infection, and subpopulations of lymphocytes. CONCLUSIONS: These preliminary results suggest that irradiation of already leukocyte-depleted blood products may not be necessary and beneficial in liver transplant recipients.

Adult↗
PubMed2006

Cytokine generation in stored platelet concentrate: comparison of two methods of preparation.

BACKGROUND & OBJECTIVES: Contaminating white blood cells (WBCs) in stored platelet concentrates (PC) are the main source of pro-inflammatory cytokines including interleukin-6 (IL-6), interleukin- 8 (IL-8) and tumour necrosis factor-alpha (TNF-alpha) that are implicated in transfusion reactions. We compared the levels of these cytokines in stored platelet preparations prepared by two methods. Effect of pre-storage leucofiltration on these cytokine levels was also studied. METHODS: Twelve units of pooled PCs were prepared by platelet rich plasma (PRP) method and buffy-coat (BC) method each and stored for 5 days. IL-6, IL-8 and TNF-alpha levels were measured in platelet supernatants on day 0, 1, 3 and 5 of the storage using commercially available immunoassays. Pre-storage leucofiltration was done in 4-pooled units of PRP-PC and cytokine levels compared with unfiltered PCs. RESULTS: Median IL-6 levels increased from day 0 to day 5 in both PRP-PC and BC-PC. In PRP-PC, IL-8 increased from <3 pg/ml on day 0 to 817 pg/ml on day 5, while in BC-PC the corresponding levels were 10 and 346.5 pg/ml, respectively. No significant increase in levels of TNF-alpha was observed in BC-PC during storage period, while levels increased significantly in PRP-PC on day 1 only. There was no significant change in the levels of all three cytokines in leucofiltered PCs over 5 days of storage. INTERPRETATION & CONCLUSION: Findings of our study showed that method of preparation and WBC content are the critical factors in determining the cytokine levels in stored PCs.

Blood Platelets↗
PubMedDate not supplied

Leukapheresis of a five-year-old girl with chronic granulocytic leukemia.

A therapeutic leukapheresis of a five-year-old girl with adult-type chronic granulocytic leukemia is described, with techniques for minimizing the effects of hypovolemia. The patient's unduly rapid response to chemotherapy suggested that the procedure had effected a substantial reduction in the leukocyte mass.

Blood Transfusion, Autologous↗
PubMed2001

Cytomegalovirus infectivity in whole blood following leukocyte reduction by filtration.

Cytomegalovirus (CMV) may be transmitted by transfusion of whole blood and cellular components processed according to standard processing procedures. A need exists to develop new procedures to remove CMV and other leukocyte-borne viruses from donor blood. Ten patients (AIDS/bone marrow transplants) who were CMV antigenemic (virus subsequently confirmed by isolation), donated 50 mL of venous blood within 24 to 72 hours of the initial antigen detection. Twenty-five-milliliter aliquots of each specimen were passed through Purecell Neo Neonatal Leukocyte Reduction Filters (Pall, East Hills, NY). The remaining 25-mL nonfiltered aliquots, as well as the blood filtrates, were subjected to infectivity endpoint determinations. The Purecell Neo filter effected a 3 to 4 log10 leukocyte reduction. CMV input titers ranged from less than 10 to 7.3 x 10(1) median tissue culture infectious dose (TCID50) per milliliter. CMV was not isolated from any postfiltration effluent (i.e., leukocytes, erythrocytes, or plasma). CMV DNA was not detected by nested polymerase chain reaction in 8 of 10 postfiltrate blood specimens. The Purecell Neo filter was efficacious in eliminating or significantly reducing viral (CMV) load in venous blood.

Adult↗
PubMed1984

Effect of Rhodococcus equi on equine polymorphonuclear leukocyte function.

A procedure was developed for isolating large numbers of purified polymorphonuclear leukocytes (PMNs) from the peripheral blood of horses. Equine PMN function was evaluated by three procedures: 1) Staphylococcus aureus ingestion, 2) nitroblue tetrazolium reduction, and 3) iodination. Four preparations of R. equi were added to polymorphonuclear leukocytes (PMNs) in each test system. Live bacteria, heat-killed bacteria, the washed pellet from heat-killed bacteria, and the supernatant fluid from heat-killed bacteria were evaluated for effects on equine PMN function. None of the R. equi preparations had an effect on S. aureus ingestion by equine PMNs. Nitroblue tetrazolium reduction by PMNs, a measure of oxidative metabolism, was suppressed by pellet and supernatant fractions. Values for the iodination reaction were depressed by all R. equi preparations, indicating decreased activity of the myeloperoxidase-H2O2-halide system of the PMN. Further evaluation of the supernatant from heat-killed R. equi showed that it retained its inhibitory effect on iodination following autoclaving and/or passage through a 10,000 MW filter. R. equi fractions did not alter the enzymatic conversion of 125I to a protein-bound form in a PMN-free assay developed to evaluate this reaction. The presence of a surface component capable of inhibiting bactericidal mechanisms of the PMN may play an important role in intracellular survival of R. equi.

Animals↗
PubMed1985

Acute cytoreduction techniques in the early treatment of hyperleukocytosis associated with childhood hematologic malignancies.

Early and effective cytoreduction for high peripheral white blood cell counts in pediatric patients with acute leukemia may be helpful in preventing complications secondary to hyperviscosity. It also may be a useful adjunct to systemic chemotherapy. As an alternative to automated apheresis for this purpose, manual exchange transfusion is efficacious and does not require hemapheresis instrumentation and disposables and the related special staff. Two patients, a neonate with acute myeloblastic leukemia and a white blood cell count of 422.2 k/microliter as well as a 2 1/2-year-old with an admission diagnosis of acute promyelocytic leukemia and a white blood cell count of 617.4 k/microliter, underwent manual exchange hemotherapy for acute cytoreduction. The procedures were tolerated well, and significant leukocyte removal was achieved, with the respective leukocyte reductions being 81.1 and 68.7%. The techniques available for pediatric cytoreduction are compared, with emphasis on their efficiency and safety and appropriateness for very small children.

Acute Disease↗
PubMed1980

Dihydropteridine reductase deficiency: diagnosis by leukocyte enzyme assay.

An assay procedure for dihydropteridine reductase in peripheral leukocytes is described. The assay utilizes the tetrahydropterin-dependent reduction of ferri-cytochrome C in the presence of NADH and requires a smaller number of cells than assays described for cultured skin fibroblasts. Dihydropteridine reductase activity was not detectable in the peripheral leukocytes nor in the cultured skin fibroblasts from two adolescent patients with malignant hyperphenylalaninemia. The parents of the patients showed approximately 50% of normal dihydropteridine reductase activity in their peripheral leukocytes. Immunochemical experiments using antibodies against bovine liver dihydropteridine reductase suggest that normal leukocytes and skin fibroblasts contain dihydropteridine reductase which is immunologically similar to that of human liver. The present studies indicate that the determination of dihydropteridine reductase activity in peripheral leukocytes can be used to diagnose hyperphenylalaninemia due to a defect in dihydropteridine reductase.

Amino Acid Metabolism, Inborn Errors↗
PubMed1995

Peripheral blood stem cell collection in a patient with chronic myelogenous leukemia and a high circulating nucleated red cell fraction.

A high level of circulating nucleated red blood cells (NRBC) in patients with chronic myeloproliferative syndromes could potentially complicate peripheral blood stem cell (PSC) collection. The mononuclear NRBC might comprise a significant fraction of the total mononuclear cells in the final product. We report a successful PSC collection in a patient with more NRBC than WBC in the peripheral blood. A 27-year-old man with chronic myelogenous leukemia underwent eight PSC collection procedures, seven using the Cobe Spectra (Spectra) and one using the Fenwal CS3000 Plus (CS). PSC product manipulations to remove NRBC were unnecessary. As assessed by post-collection NRBC: WBC ratio as a percent of the initial ratio, Spectra selectively harvested mononuclear leukocytes over NRBC. The collected products had a mean NRBC: WBC ratio that was 3.4% of the peripheral blood ratio. Adequate numbers of mononuclear leukocytes were collected with less than 6% NRBC contamination. The single CS procedure resulted in a comparable NRBC reduction efficiency as the Spectra. We conclude that PSC harvest using automated blood cell separators from patients with a high level of circulating NRBC may result in a product with an acceptable number of NRBC.

Adult↗
PubMedDate not supplied

Filtering out the confusion about leukocyte-poor blood components.

During the past decade, intensive investigation into the adverse clinical potential of leukocytes in red cell and platelet products has been undertaken. Clinical data indicated several benefits associated with the delivery of leukocyte-depleted blood products. These benefits include a reduction in nonhemolytic febrile transfusion reactions, human leukocyte antigen alloimmunization, and viral transmission. In response to such findings, several procedures and devices have been designed to remove leukocytes from blood components.

Blood Component Transfusion↗
PubMed1977

Tuftsin and some analogs: synthesis and interaction with human polymorphonuclear leukocytes.

The phagocytosis-stimulating tetrapeptide tuftsin, L-threonyl-L-lysyl-L-prolyl-L-arginine, was synthesized by both conventional and polymeric-reagent approaches. Using a combination of the two methods several analogs were prepared, including: [Ala1]tuftsin, [Lys1]tuftsin, [Ser1]tuftsin, [Val1]tuftsin, acetyl-tuftsin, p-aminophenylacetyl-tuftsin and tyrosyl-tuftsin. [Des-Thr1]tuftsin and [omega-NO2(4)]tuftsin were synthesized using a conventional procedure. The effects of synthetic peptides on the phagocytosis of heat-killed yeasts and on the reduction of the dye nitroblue tetrazolium by normal human polymorphonuclear leukocytes were investigated. Tuftsin and to a lesser extent [Lys1]tuftsin and [Ser1]tuftsin were found to stimulate phagocytosis, whereas the other analogs synthesized as well as [Ser1]tuftsin exhibited inhibitory effects to tuftsin's action. Tuftsin alone has stimulated nitroblue tetrazolium reduction; [Des-Thr1]tuftsin and [Ala1]tuftsin repressed this stimulation, while the other peptides showed no effect.

Hexosephosphates↗
PubMed1989

The isolation of B lymphocytes from human peripheral blood using antibodies coupled to paramagnetic particles and rosetting techniques.

A method is described for the complete removal of monocytes and a reduction of natural killer cells from a suspension of peripheral blood mononuclear leukocytes. The cells are depleted in a batch procedure employing monoclonal antibodies coupled to paramagnetic particles. The bound cells are removed with the help of a magnet. The resulting cell population, which contains less than 1% esterase positive cells and a fraction of the natural killer cells originally present, can be further depleted of T lymphocytes by erythrocyte-rosetting techniques.

Antibodies, Monoclonal↗
PubMed2007

Sperm quality and pregnancy rate after COX-2 inhibitor therapy of infertile males with abacterial leukocytospermia.

BACKGROUND: Leukocytes are a frequent finding in seminal plasma of infertile males with abacterial inflammation. We evaluated the effects of treatment with rofecoxib, a cyclooxygenase-2 inhibitor, on sperm quality and pregnancy rate after intrauterine insemination (IUI) or monitored intercourse. METHODS: We selected 47 infertile patients referred to our sterility centre for semen analysis. Sperm evaluation was performed by light microscopy with Papanicolau and eosin staining, before and 1 month after therapy. Swim-up selection was carried out in two steps. Starting 6-8 weeks after the end of therapy, couples underwent different procedures of assisted fertilization according to their semen parameters. RESULTS: Semen analysis 30 days after the end of therapy showed a significant reduction in leukocyte concentrations with respect to baseline, an improvement of sperm motility and morphology, particularly the presence and shape of the acrosomal complex and tail structure. After monitored intercourse and IUI, pregnancy rate was 15.8 and 11.3%, respectively. CONCLUSIONS: Our results suggest that a decrease in leukocytospermia after rofecoxib therapy was associated with recovery of all seminal characteristics in basal and swim-up selected samples. This general improvement could justify the positive outcome of ART after anti-inflammatory therapy.

Adult↗
PubMed1989

A direct approach in fibrinolysis diagnostic: mimicry of the leukocyte by attack by oxidants.

Activated leukocytes release large amounts of chloramine like oxidizing agents (see Weiss et al. Science 222, 625-628, 1983) which inactivate protease inhibitors, creating microenvironments of uncontrolled protease activity. The biological result is an increased proteo- and fibrino- lysis. Functional determination of tissue type (t-PA) or urinary type (u-PA) plasminogen activator, the key enzymes of fibrinolysis, is of clinical importance. Assay techniques have been developed but are troublesome due to predilution, acidification or separation steps in order to eliminate the PA and plasmin inhibiting effect of plasmatic inhibitors of anti-PA and of anti-plasmin type, respectively. In this study, evidence is presented that performance of fibrinolytic assays using N-chloroamines offers great advantage: plasmatic plasminogen activator activity both of urinary and of tissue type can be measured precisely within minutes in untreated (direct) plasma samples. Therefore, mimicking the oxidative inflammatory response, for the first time it gets feasible to analyze blood factors involved in the physiological course of fibrinolysis by means of a functional, sensitive, and rapid assay procedure.

Chloramines↗
PubMed1999

Quality and clinical response to transfusion of prestorage white cell-reduced apheresis platelets prepared by use of an in-line white cell-reduction system.

BACKGROUND: This study evaluated the quality and clinical effectiveness of white cell (WBC)-reduced apheresis platelets collected by the use of a new technology, fluidized particle-bed separation. STUDY DESIGN AND METHODS: In phase 1, six suitable donors underwent two separate plateletpheresis procedures on one occasion, each separated by less than 10 minutes. In random order, a control unit was collected with the COBE Spectra and a test unit with the Spectra Leukocyte-Reduction System (LRS). The quality of apheresis platelet components was assessed by an in vitro test panel, and residual WBCs were counted by Nageotte chamber and flow cytometric methods. For the in vivo studies, the test and control units were randomly labeled with either 51Cr or 111In at the end of storage and transfused simultaneously to the donor. Samples were taken for calculation of platelet survival and recovery. In phase II, 109 thrombocytopenic patients were given platelets collected by use of the Spectra LRS. RESULTS: Test platelets had significantly fewer residual WBCs (median 7.6 x 10(4)) than control platelets (median 3.9 x 10(5)), with equivalent in vitro function values. Test and control platelets had similar recovery and survival. Transfused platelets collected by use of the LRS achieved a mean 1-hour corrected-count increment of 19.3. CONCLUSION: The LRS collects platelet components with significantly lower WBC contamination without adverse effects on the function or in vivo survival of the platelets.

Blood Platelets↗