Leukocyte reduction filters as an alternative source of peripheral blood leukocytes for research

ABSTRACT Introduction: Peripheral blood leukocytes are a suitable cell model for science research. However, blood samples from healthy volunteers are limited in volume and difficult to obtain due to the complexity of volunteer recruitment. Objective: Therefore, it is urgent to find an alternative source of peripheral blood leukocytes. Method: One of the possibilities is the use of leukocyte reduction filters (LRFs) in blood banks that is used for preparation of leukoreduced blood products. More than 90% of the leukocytes are trapped in the leukofilters allowing the desired blood product to pass through. Results: It has been reported that the biological function of leukocytes collected from the filters are no different from those isolated from buffy coats, leukapheresis products and whole blood (WB) cells. Moreover, LRFs are waste products that are discarded after leukoreduction. Conclusion: Thus, leukofilters represent an economic source of human cell populations that can be used for a variety of investigative purposes, with no cost. In the present study, we reviewed the different usage of LRFs in the research, clinical and commercial applications.

Effect of modified blood bag catheter transfer on reducing discard rate of leukocyte-depleted blood / 中国输血杂志

【Objective】 To observe the application of the traditional and modified catheter transfer method in leukocyte-depleted blood preparation and the effect of modified method on reducing the blood discard rate due to hot joint leakage. 【Methods】 After leucocyte filtration, the traditional method is to seal the product bag catheter directly and then connect the whole blood catheter, while the modified method is to seal the two sections on the product bag catheter and then connect the whole blood catheter at the distal seal. The blood discard rates of the two methods due to the hot joint leakage in the catheter connection of leukocyte reduction were analyzed. 【Results】 After repeated training for the staff, using the same type of equipment, the blood discard rate due to heat sealing leakage by modified method was 0(0/33 595), significantly lower than that by traditional method(0.11%, 36/32 873, P<0.001). 【Conclusion】 The modified method can significantly reduce the discard rate of blood due to seal leakage and save valuable blood resources. However, there is still a risk of seal leakage, and staff should take preventive measures against occupational exposure

Effects of irradiation and leukoreduction on down-regulation of CXCL-8 and storage lesion in stored canine whole blood

White blood cells (WBCs) and storage period are the main factors of transfusion reactions. In the present study, cytokine/chemokine concentrations after leukoreduction (LR) and irradiation (IR) in stored canine whole blood were measured. Red blood cell storage lesion caused by IR and LR were also compared. Blood samples from 10 healthy Beagles were divided into four groups (no treatment, LR-, IR-, and LR + IR-treated). Leukocytes were removed by filtration in the LR group and gamma radiation (25 Gy) was applied in the IR group. Immunologic factors (WBCs, interleukin-6 [IL-6], C-X-C motif chemokine ligand 8 [CXCL-8], and tumor necrosis factor-alpha) and storage lesion factors (blood pH, potassium, and hemolysis) were evaluated on storage days 0, 7, 14, 21, and 28. Compared to the treated groups, IL-6 and CXCL-8 concentrations during storage were significantly higher in the control (no treatment) group. LR did not show changes in cytokine/chemokine concentrations, and storage lesion presence was relatively mild. IR significantly increased CXCL-8 after 14 days of storage, but IR of leukoreduced blood did not increase CXCL-8 during 28 days of storage. Storage lesions such as hemolysis, increased potassium, and low pH were observed 7 days after IR and storage of blood, regardless of LR. IR of leukoreduced blood is beneficial to avoid immune reactions; however, storage lesions should be considered upon storage.

Effect of caffeic acid on radiotherapy-induced hypocytosis in patients with lung cancer / 中国综合临床

Objective To investigate the clinical effect of caffeic acid tablets on hypocytosis induced by radiotherapy in patients with lung cancer. Methods From January 2017 to October 2015,one hundred and twenty patients with lung cancer treated by radiotherapy in No. 88 Hospital of PLA were selected and randomly divided into the observation group and the control group,60 cases in each group. Patients in the observation group were treated by oral caffeic acid tablets 0. 3 g/time,3 times/d until the end of radiotherapy. The control group was treated with radiotherapy alone and did not take any blood raising drugs. When myelosuppression appeared, recombinant human granulocyte colony-stimulating factor Injection or recombinant human interleukin 11 was given till it turned to normal blood. The incidence rate of bone marrow suppression,number of white blood cells (WBC),platelet (PLT) and the efficacy of radiotherapy were observed. Results The incidence rate of bone marrow suppression of the observation group was 16. 67％( 10/60) ,which was significantly lower than that of the control group ( 63. 33％( 38/60 ) ) . The difference was statistically significant (χ2 = 27. 22, P<0. 05 ); the incidence of bone marrow inhibition in the observation group was 0,while the control group was 15. 00％ (9/60) ,and the difference was statistically significant (χ2=9. 73,P<0. 05) . The number of white blood cells and platelets decreased significantly in the two groups after radiotherapy. The number of leukocytes and platelets in the observation group at 1,2,3 and 4 weeks after radiotherapy were significantly higher than those in the control group,the difference was statistically significant (P<0. 05). The effective rate of radiotherapy was 70. 00％ (42/60) in the observation group and 66. 67％ (40/60) in the control group,with no significant difference (χ2=0. 15,P>0. 05) . Conclusion Caffeic acid tablet is effective in preventing leukocyte and thrombocytopenia caused by bone marrow suppression in patients with lung cancer after radiotherapy.

Survey on the Usage of Leukocyte Reduced and Irradiated Blood Components in Korea (2007~2013) / 대한수혈학회지

BACKGROUND: Leukocyte reduced (LR) and irradiated (IR) blood components are used to prevent immunological transfusion-related adverse reactions. However, so far, reports on the usage of LR or IR blood components in Korea are scarce. METHODS: Data from January, 2007 to December, 2013 provided by the Health Insurance Review and Assessment Service of Korea were analyzed. Disease categories of the patients were classified according to the Korean Standard Classification of Disease. RESULTS: In 2013, 26.7% of total transfused blood components were leukocyte reduced and an increase of 5.3% compared to 2007. The proportion of IR components increased from 21.4% in 2007 to 27.9% in 2013. The percentage of LR (IR) blood components for RBCs, platelets, and SDPs was 15.4% (14.7%), 35.1% (38.8%), and 75.2% (80.1%), respectively, in 2013. In particular, the percentage of IR FFPs units increased gradually over the years, from 11.2% in 2007 to 22.7% in 2013. LR and IR components were used mainly in hemato-oncology patients but the proportion showed a downward trend. Due to aging of the society, transfusion of LR and IR components has inclined trends in the 70's or more. CONCLUSION: Although the transfusion rate of both LR and IR blood component is increasing, it is still remarkably lower than that in developed countries. Therefore, LR and IR blood components should be used more extensively. For this, reimbursement criteria for National Health Insurance for these blood components should be extended and the fee schedule for LR and IR blood components should be adjusted to reflect clinical practice and patient need.

Development and Preliminary Evaluation of a Leukocyte Removal Aptamer Filter / 대한수혈학회지

BACKGROUND: Leukocyte reduction filters are widely used to prevent transfusion reactions caused by leukocytes in blood components. Commercial filters are not sufficient for removal of leukocytes for prevention of transfusion associated graft-versus-host disease; therefore, irradiation of blood components was performed using expensive equipment. Techniques using an aptamer substituted for antibody have been developed and are available in clinical areas. The purpose of this study is to develop the aptamer filter system and to evaluate its efficiency and the possibility of its clinical application. METHODS: Aptamers targeted to CD45 were selected by the Postech Aptamer Initiative. The aptamer filter in which aptamers attached to beads were bound to leukocytes and removed by magnetic field was developed. Filtration of 14 units of leukoreduction-red blood provided by Korean Red Cross Blood Services was performed using aptamer filters. Leukocyte removal rate and red cell recovery rate were evaluated and bacterial culture was performed. RESULTS: After filtration using the aptamer filters, 45.6% of leukocytes were additionally removed and the red cell recovery rate was 92.8%. No growth in the bacterial culture was observed. CONCLUSION: In order to apply the cell depletion technique utilizing an aptamer to blood filter system, we developed and evaluated the aptamer filter system. Through improvement of the binding efficiency of the aptamer and the filtering process, and application of the various aptamers for other different cells, we suggest that this technique can be applied in the clinical area, such as a substitution for the irradiation process for TAGVHD prevention.

The Characteristics of Residual Leukocyte in Sepacell PLS-5A Filtered Platelet Concentrates / 대한혈액학회지

BACKGROUND: We evaluated residual leukocytes characteristics of white cell(WBC) reduction filter in platelet concentrates. Differential count and lymphocyte subset changes were measured before and after leukocyte filtration in platelet concentrates. MATERIAL AND METHODS: Ten units of platelet concentrates were prepared and were filtered with WBC-reduction filter(Sepacell PLS 5A, Japan). After filtration of blood products, WBC and differential leukocyte count and lymphocyte subsets were counted by microscopic examination of Wright-Giemsa stained smear and Facscan(Becton-Dickinson, USA). Monoclonal antibodies used for lymphocyte subset test were CD3(FITC), CD4(FITC), CD8(PE), CDl4(PE), CDl6(PE), CDl9(PE), CD33(PE), CD56(PE), IgGl(FITC), IgG2(PE). RESULTS: The main population of residual leukocytes after filtration was mainly lymphocytes(96.7%), and CD3 positive T lymphocytes showed 23.8% positivity of residual leukocyctes and the next were NK cell(8.7%). B lymphocytes were rarely found(<0.01%) and CD4/ CD8 ratio was within normal limits. CONCLUSION: The leukocyte reduction filters(Sepacell PLS-5A) would be effective for prevention of platelet alloimmunization but not sure about the effect for prevention of TA GVHD.