RESUMEN
ObjectiveThe aim of this study is to investigate change of platelet count in red blood cell （RBC） units at different storage periods and explore the efficiency of platelet removal by leukocyte filter. MethodsA total of 58 RBC units were divided into four groups according to different storage periods： 1 week Group （16）， 2 weeks Group （16）， 3 weeks Group （14） and 4 weeks Group （12）. RBC units in the four groups were filtered through leukocyte filter. The RBC samples before and after filtration were obtained. The platelet count was detected by automatic blood cell counter and the efficiency of platelet removal was calculated. RBC samples before filtration were made into blood cell smears. The blood cell smears were dyed with Wright-Giemsa stain， and the morphology of platelets was observed through a microscope. ResultsThe platelet count in RBC units stored for 1， 2， 3 and 4 weeks was （286.5±62.34）×109/L， （238.0±57.37）×109/L， （193.6±56.21）×109/L and （167.8±24.76）×109/L， respectively. Platelet count in blood stored for 3 weeks （P<0.01） and 4 weeks （P <0.000 1） were significantly lower than those stored for 1 weeks. When observed in the blood smears of RBC units at different storage periods， platelets with normal morphology were distributed in clump and scattered style. The platelet removal rates of the four groups were （80.13±9.06） %， （76.41±10.13） %， （77.78±9.30） % and （70.63±9.39） %， respectively， with no significant difference （P >0.05）. ConclusionsPlatelet count in RBC units decreases gradually as the storage period increases， but most platelets still remain in RBC units of late storage periods （3 weeks and 4 weeks）. The leukocyte filter is able to remove most of the platelets， and the removal efficiency is similar among the groups.
RESUMEN
【Objective】 To investigate the effect of leukocyte filter in removal of tumor cells in blood and the viability of using leukocyte filter in intraoperative cell salvage in tumor patients. 【Methods】 The leucocyte-depleted suspended RBCs prepared from 200 mL human whole blood were spiked with HCT116 cells cultured in vitro to simulate the autologous blood recovered from tumor patients during operation. Conventional filter (group A, n=6), filter with small pore size (group B, n=6) and filter with thicker membrane and small pore size (group C, n=6)) were used. The CD45-EpCAM+ tumor cells were detected by anti-CD45-PE and anti-CD326 (EpCAM)-FITC flow cytometry, and the absolute count of tumor cells were calculated using Flow Count fluorescence microspheres. The activity of tumor cells was detected by cell culture and trypan blue staining. Furthermore, blood biochemical indexes (LDH, K+ ) and red cell recovery rate were detected. 【Results】 Tumor cell counts before and after the application of leukocyte filter A, B, C were(1.52±0.48)×107/mL vs(2.73±1.74)×104/mL, (1.48±0.55)×107/ml vs(2.96±1.85)×104/mL and (1.44±0.46)×107/mL vs(3.08±2.33)×104/mL, respectively (P >0.05), which was significantly reduced after filtration (P < 0.01). No viable cells were found in the filtered blood cultured for 7 days. There were no significant differences in K+ and LDH value before and after filtration among the three groups(P >0.05). The blood recovery rates of group A, B, C were 85.22%, 84.97% and 82.86%, respectively. 【Conclusion】 The conventional filter can significantly reduce the number of circulating tumor cells, and it is feasible for intraoperative cell salvage in tumor patients.