Abstract

 Background and Objectives

 White blood cells (WBCs) in blood products are the major stimulus for a number of detrirmental biological reactions including febrile nonhemolytic transfusion reactions, alloimmunization against HLA antigens, and cytomegalovirus transmission. In this study, our objective was to study the effect of storage time on the filtration of platelet concentrates (PCs). The total number of white blood cells as well as the distribution of WBC subsets in PC units filtered before and after storage was compared.

 Materials and Methods

 In this experimental study, platelet-rich plasma-derived PCs (5 pooled units) were filtered both fresh and after 5 days of storage then, the total number of WBCs was calculated by flow cytometry and cell counting. WBC subsets were analyzed by flow cytometry with three-color fluorescence. In this study, the third genaration bags and filters were used.

 Results

 Before filtration, the total number of WBC was significantly higher in fresh units compared with stored units, whereas in postfiltration samples the number of white blood cells was significantly lower in the fresh compared with the stored units. Although the absolute number of WBCs significantly reduced, filtration induced significant changes in proportion in subsets in both fresh and stored units the percentage of B cells and monocytes increased after filtration.

 Conclusions

 Both pre- and post-storage WBC filtration affect the proportions of WBCs in the final product but pre-storage WBC filtration of platelet concentrates is superior than post-storage WBC filtration.

 Key words : White blood cells, Platelet concentrates, Blood, Filtration 

  Abstract

 Background and Objectives

 White blood cells (WBCs) are present in all cellular blood components which are prepared by standard techniques. Studies have shown that leucocytes can cause a variety of side effects after transfusion. Clinical reactions may be attributed to specific leucocyte subsets. Leukodepletion filters reduce leucocytes and some of their adverse effects. The aim of this study was to evaluate leucocyte subpopulations in whole blood prior and after Prestorage filter leukodepletion it was performed in Iranian Blood Transfusion Organization.

 Materials and Methods

 In this experimental study, different leukocyte subpopulations in whole blood were identified and quantified before and after filtration in a blood collection system having integral whole blood filtration (Baxter Fenwal, USA) equipped with RZ 2000 (Asahi, Japan) filters. Leucocytes were analysed by flowcytometry with monoclonal antibodies specific for CD45, CD19, CD3, CD14 and CD13. Statistical analysis was performed through SPSS software.

 Results

 Leukodepletion by this type of filter reduced the leukocyte load by 2.8 log 10 on average. The proportion of PMNs (CD13⁺) and monocytes (CD14⁺) to total number of leucocytes (CD45⁺) significantly reduced, but that of CD3⁺ and CD19⁺ cells showed no considerable differences before and after filtration.

 Conclusions

 This type of filter caused difference in leucocyte subset distribution after filtration. It appears that these distributions were cell size dependent. Filtration also reduced the absolute number of WBCs significantly.

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 Key words : Filtration, Flowcytometry, White blood cell