Differential expression of exosomal microRNAs in fresh and senescent apheresis platelet concentrates.

Patients have a high risk of suffering adverse reactions after receiving platelet products stored for 5 days. Bioactive exosomes in platelet products can be accumulated during storage, which is associated with adverse reactions. MicroRNAs are one of the critical cargoes in exosomes, which participate in cell differentiation, metabolism, and immunomodulation. This study intends to elucidate and analyze the differential expression of exosomal microRNAs in apheresis platelet concentrates during storage and predict the potential functions of target genes. Apheresis platelet concentrates were used to isolate exosomes by ultracentrifugation. Exosomes were phenotyped by western blot, transmission electron microscopy, and nano flow cytometry. The differential expression of the exosomal microRNAs was obtained by a microarray test using four bags of apheresis platelets stored for 5 days compared with 1 day. The differentially expressed microRNAs between the two time points were identified, and their target genes were analyzed by miRWalk and miRDB. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to predict the target genes' functions. Fifteen bags of apheresis platelet concentrates stored for 1 day and 5 days were used to verify the microarray results by quantitative reverse transcription-polymerase chain reactions (qRT-PCR). There were 134 microRNAs in total expressed differently in the two groups (day 1 and day 5), with 57 microRNAs up-regulated and 77 down-regulated (|fold change| > 2.0 and P < .05). Thirteen up-regulated microRNAs (hsa-miR-22-3p, hsa-miR-223-3p, hsa-miR-21-5p, hsa-miR-23a-3p, hsa-miR-320b, hsa-let-7a-5p, hsa-miR-25-3p, hsa-miR-126-3p, hsa-miR-320c, hsa-miR-342-3p, hsa-miR-320d, hsa-miR-328-3p, and hsa-miR-320e) detected in all samples were selected to validate the results. The qRT-PCR results showed that five (hsa-miR-22-3p, hsa-miR-223-3p, hsa-miR-21-5p, hsa-miR-23a-3p, and hsa-miR-320b) of them were increased more than 10-fold (P < .001); four (hsa-let-7a-5p, hsa-miR-25-3p, hsa-miR-126-3p, hsa-miR-320c) more than five-fold (P < .001); two (hsa-miR-342-3p and hsa-miR-320d) more than two-fold (P < .05); and two (hsa-miR-328-3p and hsa-miR-320e) more than two-fold (P > .05). Specifically, hsa-miR-22-3p increased 14.6-fold; hsa-miR-223-3p increased 13.0-fold; and hsa-miR-21-5p increased 12.0-fold. Based on bioinformatics functional analysis, target genes of top nine microRNAs (hsa-miR-22-3p, hsa-miR-223-3p, hsa-miR-21-5p, hsa-miR-23a-3p, hsa-miR-320b, hsa-let-7a-5p, hsa-miR-25-3p, hsa-miR-126-3p, and hsa-miR-320c) were annotated with positive regulation of cell proliferation and nervous system development, and mainly enriched in regulating pluripotency of stem cells signaling pathway, prolactin signaling pathway, and FoxO signaling pathway, etc. The prolactin, FoxO, ErbB, and TNF signaling pathway were relevant to immunomodulation. In particular, hsa-miR-22-3p expression was the most different during storage, with a fold change of 14.6, which might be a key mediator.

What is the context? Platelet transfusion is a widely used clinical treatment, but it is not totally safe. Side effects may happen to patients who receive the "older" platelet products. Exosomes in platelet products can be transfused to patients while receiving blood. Exosomes are accumulated in platelet products during storage. MicroRNAs are one of the important cargoes in exosomes, which can be delivered to the target cells, thus affecting their functions.This study aims to investigate and analyze the differential expression profiling of exosomal microRNAs in apheresis platelet concentrates during storage, and predict the potential function of the target genes. We found out the top nine differentially expressed microRNAs got involved in positive regulation of cell proliferation and nervous system development, and mainly enriched in regulating pluripotency of stem cells signaling pathway, prolactin signaling pathway, and FoxO signaling pathway, etc.What's new? Our study is the first one to test the exosomal microRNAs in the apheresis platelet concentrates. The apheresis platelet concentrates were stored for 1 day and 5 days. Compared the two time points, we obtained the differential expression profiling of exosomal microRNAs. Based on bioinformatics analyses and qRT-PCR results, we provided nine up-regulated microRNAs which might be critical mediators to communicate with target cells after transfusing.What's the impact? This study expands our knowledge of exosomal microRNA expression profiling from apheresis platelet concentrates along different storage periods. This might be relevant to immunomodulation in post transfusion situations.

Pathogen inactivation treatment of triple-dose apheresis platelets with amotosalen and ultraviolet a light.

BACKGROUND: A triple storage (TS) set allows for pathogen inactivation (PI) treatment of triple-dose apheresis platelet products with amotosalen + UVA. We evaluated the quality and metabolic parameters of platelet concentrates (PCs) pathogen inactivated and stored for 7 days. MATERIALS AND METHODS: Twelve triple-dose products collected with two different apheresis platforms were treated with amotosalen+UVA. Products were split into three single-dose units. Testing was made pretreatment, after splitting, at days 5 and 7 of storage. RESULTS: Single-dose PI PCs had a mean platelet content of 2.89 ± 0.35 x 1011 . From baseline to day 7, pH remained stable (7.1 ± 0.1 vs. 7.0 ± 0.1), pO2 increased (11.3 ± 2.4 vs. 18.3 ± 3.5 kPa) as did LDH (201 ± 119 vs. 324 ± 203 U/L) and lactate (3.6 ± 1.7 vs. 12.1 ± 1.5 mmol/L) (all p < 0.01); pCO2 decreased (4.1 ± 0.8 vs. 1.5 ± 0.7 mmHg; p < 0.01) and so did bicarbonate (6.6 ± 1.1 vs. 2.5 ± 1.4 mmol/L), glucose (5.6 ± 1.2 vs. 0.4 ± 0.4 mmol/L) and ATP (3.4 ± 0.9 vs. 2.5 ± 1.4 nmol/108 platelets) (all p < 0.05). CONCLUSION: Triple-dose PCs processed with the TS sets fulfilled the quality requirements and displayed metabolic changes of expected extent during 7-day storage.

Optimal collecting policy for apheresis platelets in a regional blood center.

BACKGROUND AND OBJECTIVES: Planning platelet collection and inventory must rely not only on adequate forecasts of transfusion demand but also sophisticated mathematical modeling techniques. This research aims to develop a better demand forecasting model of apheresis platelets and a mathematical programming model to determine the best target amounts of apheresis platelet collection. MATERIALS AND METHODS: Time series data of apheresis platelets collected from donors and platelets supplied to hospitals daily in Taipei Blood Center from January 2014 to December 2015 was used to fit a forecasting model which combines a regression-type model for formulating the deterministic trends and seasonal variation and an autoregressive moving average model (ARMA) for explaining remaining serial correlations. A seasonal autoregressive integrated moving average (SARIMA) model was also used for benchmarking the prediction performance. A linear programming model was then formulated to solve for the optimal daily target collection volumes that maximize the total social benefits. RESULTS: The time series model achieved good predictive power with a mean absolute percentage error less than 10%. The appropriateness of the proposed target collection volumes was also verified by using a simulation model, and the proportion of the total platelets requested by hospitals that can be filled by collected apheresis platelets can increase significantly by using the new policy. CONCLUSION: The methods proposed in this study can be easily implemented to enhance the management efficiency of blood collecting and supplying of a blood center, and to decrease the costs of the blood outdates and shortages.

The use of historical platelet counts from blood donors to program apheresis platelet donation: An Australian perspective.

BACKGROUND: For Australian apheresis platelet donations, in-centre haematology analysers provided the platelet count used to program the platelet collection machines. When the haematology analysers were not functional, historical platelet counts from previous donations were used. This study aimed to confirm that the routine use of historical platelet counts for programming apheresis collection machines would maintain platelet yields within the donated units and that haematology analysers could be removed. STUDY DESIGN: A staggered implementation for the routine use of mean historical platelet counts to program apheresis platelet collection machines was conducted. The donors' full blood counts following donation were tested centrally for comparison to the historical mean. The component yields when using on-the-day platelet counts to program platelet collection were compared with those collected using historical platelet counts. For historical platelet counts to be deemed successful, the target was for 90% of the mean historical donor platelet counts to have less than 20% variance from the on-the-day platelet count. RESULTS: Over 96% of the mean historical platelet counts were within 20% variance of the platelet count on the day of donation. The component yield (platelet count x109 cell/unit) before analyser removal was 273.3 ±â€¯32.0 (n = 2639) and post-removal was 282.8 ±â€¯38.8 (n = 2689). CONCLUSION: The removal of haematology analysers from donor centres and replacement with mean historical platelet counts was successful in maintaining platelet yields. Replacement of the haematology analysers with historical platelet counts simplified regulatory compliance, reduced staff workload and costs associated with analyser registration.

Hemostatic function and transfusion efficacy of apheresis platelet concentrates treated with gamma irradiation in use for thrombocytopenic patients.

BACKGROUND: During the transfusion of blood components, the transfer of allogeneic donor white blood cells (WBCs) can mediate transfusion-associated graft-versus-host disease (TA-GVHD). To minimize the reaction, exposure of blood products to gamma irradiation is currently the standard of care. The aim of our study was to evaluate and compare hemostatic function, transfusion efficacy, and safety of gamma-irradiated single-donor apheresis platelet concentrates (PCs) and of conventional non-irradiated PCs in patients with chemotherapy-induced thrombocytopenia. METHODS: 20 double-dose single-donor leukoreduced PCs were split in two identical units; one was gamma-irradiated with 25 Gy (study arm A) and the other remains non-irradiated (study arm B). Both units were stored under equal conditions. Hematologic patients were randomly assigned to receive gamma-irradiated or conventional non-irradiated PCs. Hemostatic function was evaluated by thrombelastography (TEG). TEG measurements were taken pre transfusion and 1 and 24 h post transfusion. TEG profiles were measured, noting the time to initiate clotting (R), the angle of clot formation (α), and the maximum amplitude (clot strength (MA)). Whole blood samples were collected from these thrombocytopenic patients at 1 and 24 h for PLT count increments (CIs) and corrected count increments (CCIs) with assessments of transfusion efficacy. Time to next PLT transfusion, transfusion requirement of RBCs, active bleeding, and adverse events (AEs), were analyzed. RESULTS: No differences could be found in hemostatic function parameters (MA, R, and α) between study arms A and B (all p values > 0.096) pre transfusion as well as 1 and 24 h post transfusion. No differences between study arms A and B were observed for mean (± standard deviation (SD)) 1-hour CCI (12.83 ± 6.33 vs. 11.59 ± 5.97) and 24-hour CCI (6.56 ± 4.10 vs. 5.76 ± 4.05). Mean 1-hour CI and 24-hour CI were not significantly different in both study arms (p = 0.254 and p = 0.242 respectively). Median time to the next PC transfusion after study PC was not significantly different between groups: (2.4 vs. 2.2 days, p = 0.767). No differences could be found in transfusion requirement of red blood cells (p = 0.744) between both study arms. There were also no regarding bleeding, adverse events, and acute transfusion reaction(s). CONCLUSIONS: This study confirms safety of gamma-irradiated PCs for treatment thrombocytopenia. Hemostatic function, transfusion efficacy, bleeding, and safety of single-donor apheresis PCs treated with gamma irradiation versus untreated control PCs are comparable.

The relationship of platelet yield, donor's characteristic and apheresis instruments in China.

Platelet yield was associated with donor's characteristic and property of apheresis instruments. Here, we have analyzed the relationship of platelet yield, physiologic parameters of donors for different apheresis instruments in China. Data were consecutively retrieved from plateletapheresis donors during March 1, 2007 and March 1, 2012. Three different apheresis instruments MCS+, Amicus, Trima system were used for plateletapheresis and defined as group 1, 2 and 3 respectively. Totally 77,091 Plateletapheresis donations were performed in this study. 17 donations were finally aborted because of vasovagal reaction with syncope. 5861, 37,036, 34,177 donations were performed in group 1, 2 and 3 respectively. Hct and platelet values before donations were similar, but platelet yield and collection rate were showed significantly difference (p<0.05) among the three groups. The values of platelet and Hct in the males before donations were higher than those in the females, and the platelet yield and collection rate were showed significantly difference between the male group and female group (p<0.05). The overall reaction rate was 1.56%. Most donors were chosen the group 2 (51.6%) for next donation, followed by group 3 (33%) and group 1 (15.4%). We concluded that the platelet yield and collection rate in the male group were higher than those in the female group and the efficiency of plateletapheresis was associated with the kind of apheresis instruments and donor's characteristic. These data will help to work out suitable apheresis protocol based on the Chinese donor's characteristic.

Platelet Additive Solutions as an Alternative Storage Medium of Apheresis Platelets to Reduce ABO Antibody Titer for ABO-Incompatibility Platelet Transfusion.

Introduction Platelet additive solutions (PASs) are nutrient media commonly used to replace and reduce the need for storage plasma. They are an alternative medium to maintain high-quality platelets lasting longer on the shelf for about seven days. Platelets with high titer of ABO antibody can pose a hemolytic transfusion reaction (HTR) risk if units are given across the ABO barrier. The risk of complication is greater when group O platelet is released to non-group O patients. The PAS has been known as a safe medium, where the titer of ABO antibodies is expected to be diluted. In this study, we compared the anti-A and anti-B antibody titers of apheresis platelets in PAS and non-PAS (plasma) as the suspending media. Methods A total of 20 apheresis platelet donors were selected, with seven from blood group A, eight from blood group B, and five from blood group O. The platelets were collected using an Amicus cell separator. They were suspended in PAS and plasma before being stored at a temperature range of 22-24º C. Anti-A (blood group B and O) and Anti-B (blood group A and O) antibody titers were measured and compared between the two suspending media. Wilcoxon signed-rank test is used for statistical analysis, and a p-value <0.05 is considered significant. Results The median titer of the anti-A antibody of apheresis platelets showed a significant difference between suspended in PAS (2.50) and plasma (4.00), p=0.002. Similar findings were also seen with the median titer of the anti-B antibody of apheresis platelet, in which it showed a significant difference between suspended in PAS (2.00) and plasma (4.00), p=0.004. It was observed that there was a significant reduction in both anti-A and anti-B antibody titers in the PAS as compared to the plasma group. Conclusion The decrease in ABO antibody titer in apheresis platelets stored with PAS can be beneficial for patients. This reduces the risk of HTRs if ABO-incompatible platelet units need to be issued. Thus, using PAS as a storage medium significantly improves platelet inventory management without compromising patient safety.

[Effects of Apheresis Platelet Transfusion on PLT, MPV, PDW and PCT].

OBJECTIVE: To investigate the changes of platelet count (PLT), plateletcrit (PCT), mean platelet volume (MPV) and platelet distribution width (PDW) before and after apheresis platelet transfusion, the correlation between the parameters and their clinical significance. METHODS: A total of 38 patients who received apheresis platelet transfusion were selected, their results of blood routine test closest to the time point of apheresis platelet transfusion were consulted from hospital information system and the changes of PLT, PCT, MPV and PDW were compared before and after transfusion. The correlation between above parameters was analyzed. The correlation of body mass index (BMI) with the increased multiple and increased value after platelet infusion was also analyzed. RESULTS: Compared with pre-infusion, PLT and PCT significantly increased (both P <0.001) while MPV and PDW showed no significant difference after apheresis platelet transfusion (P >0.05). The difference of PLT and PCT before and after apheresis platelet transfusion had no correlation with PLT and PCT before transfusion (r =0.002, r =0.001), while the difference of MPV and PDW was negatively correlated with MPV and PDW before transfusion (r =-0.462, r =-0.610). The PLT growth rate was positively correlated with PCT growth rate before and after apheresis platelet transfusion (r =0.819). BMI was positively correlated with the increased multiple of PLT after infusion (r =0.721), but not with the increased value of PLT after infusion (r =0.374). CONCLUSION: Apheresis platelet transfusion can cause platelet parameters change and shows different characteristics. Characteristic changes of platelet parameters and their correlation can be used as reference indices to evaluate the efficacy of apheresis platelet transfusion.

Quality assessment of platelet concentrates prepared by platelet-rich plasma, buffy-coat, and apheresis methods in a tertiary care hospital in South India: A cross-sectional study.

INTRODUCTION: In blood banking and transfusion medicine, it is of paramount importance to improve transfusion safety and provide a higher quality of product to maximize the therapeutic outcomes and minimize the risk of developing transfusion-associated complications for patients receiving a blood transfusion. MATERIALS AND METHODS: This was a cross-sectional study conducted at the department of transfusion medicine in a tertiary care hospital of South India from February 2019 to December 2020. The primary objective of the study was to assess the quality of platelet concentrates (PC) prepared by platelet-rich plasma (PRP), buffy-coat (BC), and apheresis method. A total of 760 PCs were subjected to quality assessment, among which 124 were PRP-PC, 176 were BC-PC, and 460 were single donor platelet (SDP). RESULTS: The total percentage of platelets meeting all the six quality control parameters in PRP, BC and SDP was 78.23%, 81.81%, and 89.96%, respectively. Apheresis PCs showed a significantly higher platelet concentration per µL on comparison with whole-blood-derived platelets. BC-PCs were found to be better than PRP-PC with regard to lower white blood cell (WBC) contamination (P < 0.05) and red blood cell (RBC) contamination (P < 0.01). No statistically significant difference was found with regard to platelet yield, volume, swirling, and pH. CONCLUSION: Ex vivo quality of PCs prepared by BC-PC, PRP-PC, and apheresis-PC fulfilled the desired quality control parameters. BC-PC was better than PRP-PC in terms of lesser WBC and RBC contamination and comparable in terms of volume, platelet yield, swirling, and pH. Apheresis PCs showed a higher platelet concentration per microliter on comparison with whole-blood-derived platelets; hence in a blood center where facilities for collection of apheresis product are available, SDPs should be the choice of platelet transfusion.

[Sequencing and Proteomic Analysis of Exosomes from Apheresis Platelets in Different Storage Periods].

OBJECTIVE: To investigate the changes of gene sequencing and proteomics of apheresis platelet (AP) exosomes in different storage periods and predict the function of AP exosomes in different storage periods. METHODS: Platelets at different storage periods of 0 day (D0), 3 day (D3) and 5 day (D5) were collected, exosomes were extracted with Gradient centrifugation; gene sequencing and proteomic analysis were used to analyze the exosomes, and biological functions of platelet exosomes were analyzed and predicted by bioinformatics. Liquid mass spectrometry (LMS) was used to detect the changes and function prediction of exosomes proteins. The small RNA sequencing library was prepared, and the constructed library was sequenced and bioinformatics technology was used for data analysis. RESULTS: AP exosome iTRAQ protein analysis showed that AP exosomes stored in D3 with 55 up-regulated proteins and 94 down-regulated proteins (P<0.05, FC<0.83 or FC>1.2), while AP exosomes stored in D5 with 292 up-regulated proteins and 53 down-regulated proteins (P<0.05, FC<0.83 or FC>1.2) as compared with D0. KEGG pathway analysis showed that the proteins were mainly involved in transport and metabolism, immune system, cancer, membrane transport and other processes. There were statistically significant differences between AP exosome miRNAs in different storage days (P<0.01). The number of miRNA up-regulated and down-regulated was 374 and 255 as compared with the number of platelet exosomes miRNA stored in D3 and D0, while that was 297 and 242 in D5 and D0, and 252 and 327 in D5 and D3, respectively. The target genes of differential platelet exosome miRNAs were analyzed by GO enrichment. Target genes of differential miRNA were mainly involved in membrane composition, mainly played molecular functions binding to proteins, and participated in biological processes of transcriptional regulation. CONCLUSION: The exosome differential proteins and miRNAs in D5 are significantly different from those in the D0 of APs, and they are involved in various biological processes.

Triple apheresis platelet concentrate quality after pneumatic tube system, conveyor box, and courier transport: An observational study.

Background and Aims: Platelets are prone to activation from handling; they are therefore transported as gently as possible, most commonly by courier. Speedier methods like pneumatic tube system (PTS) transport could improve patient care but may subject platelets to mechanical stress. To test the impact of mechanical stress caused by transport, we compared a PTS with a conveyor box and courier transport on apheresis platelet function. Methods: Fourteen apheresis platelet concentrate triple donations were analyzed by light transmission aggregometry (LTA), rotational thrombelastometry (ROTEM), and flow cytometry before and after indoor transport over 800 m by PTS, conveyor, and courier, respectively, while recording shocks and vibrations with a high-frequency acceleration data logger. Shock index scores were calculated as shock intensity (g-force) times frequency. Results: The shock index was 81 for courier, 6279 for conveyor, and 9075 for PTS. Flow cytometry revealed no significant difference in platelet surface expression of CD62p before (16%) and after transport via courier (15%), conveyor (14%), or PTS (16%). LTA with adenosine phosphate and thrombin receptor-activating peptide-6 resulted in comparable platelet aggregation for courier, conveyor, and PTS. ROTEM assays showed no relevant differences in coagulation time, clot formation time, and maximum clot firmness between transport modes. Conclusion: Though the mechanical challenge was smallest with courier transport, there were no significant differences in platelet activation or aggregation between the three transport modes. These data contradict restrictions on the use of PTSs for platelet concentrate transport.

Characterization of peripheral blood mononuclear cells isolated using two kinds of leukocyte filters.

OBJECTIVE: The objective of this study was to compare the activity and biological function of leukocytes isolated using apheresis platelet leukoreduction system chambers (LRSC), whole blood leukoreduction filters (LRF), and leukocytes in unfiltered peripheral whole blood (WB). METHODS: Peripheral blood mononuclear cells (PBMCs) and granulocytes were obtained by density gradient centrifugation using recovery filters and WB. Flow cytometry was used to detect the activity, phenotype, and apoptosis ratio of each cell subtype. RESULTS: The proportion of lymphocytes obtained from PBMCs was similar when using the two different filters as compared to traditional isolation; however, there were significant differences between the monocytes and granulocytes. The phenotypic frequency of lymphocytes was similar, but the apoptosis rate of lymphocytes from the two filters was slightly higher. Additionally, monocytes isolated via the three sources were able to be induced into dendritic cells expressing specific molecules; Granulocytes isolated from the LRF showed a lower purity and a higher level of apoptosis than granulocytes isolated from the WB. CONCLUSION: Compared with WB, the PBMCs isolated from the filters used in our blood center had no statistical difference in their activity and biological function, but they did differ in the proportion and quantity of monocytes and granulocytes. Our results show that the two filters can be used as an alternative method to collect leukocytes, which solves the problem of an insufficient blood supply for clinical and basic science research. Thus, these filters have significant value beyond their practical use in clinics.

The effects of storage on platelet function in different blood products.

OBJECTIVES: Reduced platelet (PLT) function during storage has been shown for buffy-coat-derived platelet concentrates (BCP) and apheresis platelet units (AP), while for whole blood (WB) it has not been well studied. The aim of this study was to investigate PLT function in these blood products throughout storage using a novel flow cytometric assay. METHODS: Flow cytometric measurement of agonist-induced platelet aggregation, CD62P expression and PAC-1 binding during storage in BCP, AP (1-9 days at 20°C) and WB (1-21 days at 2-6°C). RESULTS: PLT-aggregation capacity decreased from day 1 to day 7 for almost all product-agonist combinations (P = .004 to P = .029) with aggregation capacity of WB being similar to that of AP and BCP. WB aggregation capacity remained relatively unchanged from day 7 to day 21. For all blood products, the fraction of agonist-induced CD62P-expression remained high and the fraction of PAC-1 binding decreased during storage. WB PLTs underwent only small changes in CD62P expression and PAC-1 binding from day 7 to day 21. CONCLUSION: This study found PLT aggregation in WB stored at 4°C to be as least as good as for BCP and AP stored at 20°C. WB retained significant PLT-aggregation capacity to day 21.

A general change of the platelet transfusion policy from apheresis platelet concentrates to pooled platelet concentrates is associated with a sharp increase in donor exposure and infection rates.

BACKGROUND: We compare the actual with the potential donor exposure and possible infection rates in the Hanover Medical School (MHH) platelet (PLT) transfusion recipients if the current MHH standard of apheresis PLT concentrate (A-PC) supply would be replaced by a pooled PLT concentrate (P-PC) transfusion regimen. DONORS PATIENTS AND METHODS: The electronic records of the MHH Institute of Transfusion Medicine and the MHH Department of Medical Controlling were evaluated to assess the development of PLT needs and supply at MHH from 2003-2006. For 2006, we evaluated all PLT transfusion recipients with respect to their overall transfusion needs, classified them for low and high PLT transfusion needs, and related them to the diagnostic groups that underlie their PLT demands. We assumed a P-PC preparation procedure using 4 whole blood-derived buffy coats for all calculations for potential donor exposure. To predict the possible infection rates of an unrecognized viral infection with low prevalence in the general population to A-PC or to P-PC recipients and the influence of neutralizing agent specific antibodies (NAB), we established a mathematical contamination/infection model based on the current PLT transfusion mode and data about GBV-C virus infection among Hanover blood donors. RESULTS: From 2003 to 2006, the 1,300-1,400 persons comprising MHH apheresis donor pool covered a 36% increase in PC transfusions. The exclusive use of P-PCs instead of A-PC would require a total of 36,240-49,276 whole blood donations to meet MHH demands, corresponding to a more than 1 log step increase in donor exposure. For individual hematological patients, the change to P-PCs would imply an 80-125%, for individual surgical patients a 40-50% higher donor exposure. Our infection model revealed an approximately 4 times higher infection. CONCLUSIONS: A change to P-PC would imply a more than one log step higher donor exposure, and an unrecognized infection with a prevalence around 1% leads to an up to 4 times higher infection rate. A general change in the PC transfusion policy that favors P-PCs is dangerous and must be avoided.

Analysis on the willingness of whole blood donors to donate apheresis platelets and its influencing factors / 中国输血杂志

【Objective】 To investigate the willingness of whole blood donors to donate apheresis platelets and analyze its influencing factors. 【Methods】 A total of 400 whole blood donors from Kunshan Blood Station and Leshan Blood Station from January to May, 2023 were surveyed by random sampling, and their willingness to donate apheresis platelets were analyzed by univariate analysis and binary logistic regression analysis. 【Results】 A total of 386 valid questionnaires were collected, with a recovery rate of 96.5%. Among the 386 whole blood donors, 177 were willing to donate apheresis platelets, accounting for 45.9%. Univariate analysis showed that gender, age, education level, blood donation times, average blood donation volume, adverse reactions to blood donation, understanding of platelets, and family members' attitude towards blood donation were the main factors affecting the willingness of whole blood donors to donate platelets, and binary logistic regression analysis showed that gender, age, blood donation times, average blood donation volume, understanding of platelets and family members' attitude towards blood donation were the main factors. 【Conclusion】 Targeted recruitment of whole blood donors should be conducted to recruit more apheresis platelet donors, so as to meet clinical demand of apheresis platelets.

Efficacy of apheresis platelet transfusion in 310 patients with haematological diseases / 中国输血杂志

【Objective】 To observe the effect of platelet transfusion in inpatients with haematological diseases, analyze the possible causes of platelet transfusion refractoriness (PTR), in order to further improve the efficacy of platelet transfusion. 【Methods】 A total of 310 patients with blood disease in our hospital from August 2020 to November 2021 who received platelet transfusion were retrospectively analyzed. Possible influencing factors of platelet transfusion, including gender, age, platelet preservation time, number of platelet transfusions, complication and red blood cell product transfusion were analyzed. 【Results】 Patients were divided into effective group and refractory group according to percentage platelet recovery (PPR) and corrected count increment (CCI). PTR was defined as PPR <20% or CCI <5 000 after two consecutive transfusions in 24 h or clinical bleeding symptoms or tendency not significantly controlled. Statistical differences were noticed between the two groups in terms of gender, pretransfusion white blood cell count, anemia, and whether antibiotics were used (P<0.05). The type of disease, gender, anemia and number of comorbidities were associated with PTR. The incidence of PTR was the highest in patients with myelodysplastic syndrome, and the incidence of PTR was higher in men than in women. Transfusion units of suspended red blood cells and the number of comorbidities were negatively correlated with the transfusion efficacy (P<0.05). 【Conclusion】 Possible influencing factors of platelet transfusion included the level of white blood cells before transfusion, use of antibiotics, anemia and transfusion of red blood cells, number of comorbidities, and type of disease, while no significant differences were found in age, hemolysis, hypersplenism, platelet preservation time, and number of platelet transfusions on transfusion efficacy.

Application of inspection sheet in apheresis platelet collection / 中国输血杂志

【Objective】 To explore the effect of inspection sheet on improving the quality of apheresis platelet, the satisfaction of blood donors and the cooperation ability of phlebotomists in the process of apheresis platelet collection. 【Methods】 Apheresis platelet donors from May to August 2021 in our center were selected as control group(without inspection sheet) and those from September to December 2021 were included in the observation group (with inspection sheet). The incidence of abnormal collection and the causes during collection process were compared between the two groups.And 100 first-time blood donors in each group were randomly selected for satisfaction survey. The questionnaire was made to investigate the phlebotomists’ recognition on the implementation of inspection sheet. 【Results】 The number of blood donors in the two groups were 6 673 and 6 559, with 111 and 49 abnormal cases, respectively. The total incidence of abnormal cases during blood collection before and after the implementation of inspection sheet was 1.66% and 0.75%, respectively, with the latter significantly lower than the former(P<0.001). The most common causes of abnormal conditions were repetitive puncture, followed by adverse reaction of blood donation, red blood cells contamination in platelet and fatty blood. The satisfaction of first-time blood donors was higher than before the implementation, and the recognition of phlebotomists on the inspection sheet was more than 90%. 【Conclusion】 The implementation of inspection sheet helps to regulate the collection process, strengthen the responsibility and service consciousness of phlebotomists, improve the satisfaction of blood donors, reduce the incidence of adverse events, and improve the quality of platelet products, which is worth popularizing in blood collection and supply institutions.

Application and effect of partnership plan competition in the recruitment of apheresis platelet donation / 中国输血杂志

【Objective】 To analyze the demographic characteristics of apheresis platelet donors who participated in the Partnership Plan Competition(PPC) of Beijing Red Cross Blood Center, and to analyze the effect of publicity and recruitment of apheresis platelet donors, so as to provide reference for formulating recruitment strategy of apheresis platelet donation. 【Methods】 Apheresis blood donors who participated in PPC from March 18, 2021 to May 18, 2021 were selected as research subjects, and their demographic data in terms of gender, age, occupation and education, and relevant blood donation data within 12 months such as the number of blood donations, whether they were regular blood donors were collected. The demographic characteristics of PPC donors and promising groups were analyzed. 【Results】 There were 58 recruiters participating in the PPC, and a total of 170 people were recruited; 53.53%(91/170) successfully participated in the donation of apheresis platelets, and 35.16%(32/91) became regular blood donors. Those 18-30 years old college male students were promising group in the PPC, and were more willing to participate in the recruitment and donation of apheresis platelets. 【Conclusion】 The PPC has significant effect on the promotion and recruitment of apheresis platelets donation. Measures such as setting the types of souvenirs according to the preferences of promising groups, strengthening publicity of PPC, encouraging non-blood donors to participate and expanding targeted recruitment can be taken in the future to increase the success rate of blood donation of the recruitment.

Effects of Apheresis Platelet Transfusion on PLT, MPV, PDW and PCT / 中国实验血液学杂志

OBJECTIVE@#To investigate the changes of platelet count (PLT), plateletcrit (PCT), mean platelet volume (MPV) and platelet distribution width (PDW) before and after apheresis platelet transfusion, the correlation between the parameters and their clinical significance.@*METHODS@#A total of 38 patients who received apheresis platelet transfusion were selected, their results of blood routine test closest to the time point of apheresis platelet transfusion were consulted from hospital information system and the changes of PLT, PCT, MPV and PDW were compared before and after transfusion. The correlation between above parameters was analyzed. The correlation of body mass index (BMI) with the increased multiple and increased value after platelet infusion was also analyzed.@*RESULTS@#Compared with pre-infusion, PLT and PCT significantly increased (both P <0.001) while MPV and PDW showed no significant difference after apheresis platelet transfusion (P >0.05). The difference of PLT and PCT before and after apheresis platelet transfusion had no correlation with PLT and PCT before transfusion (r =0.002, r =0.001), while the difference of MPV and PDW was negatively correlated with MPV and PDW before transfusion (r =-0.462, r =-0.610). The PLT growth rate was positively correlated with PCT growth rate before and after apheresis platelet transfusion (r =0.819). BMI was positively correlated with the increased multiple of PLT after infusion (r =0.721), but not with the increased value of PLT after infusion (r =0.374).@*CONCLUSION@#Apheresis platelet transfusion can cause platelet parameters change and shows different characteristics. Characteristic changes of platelet parameters and their correlation can be used as reference indices to evaluate the efficacy of apheresis platelet transfusion.

Assessment of soluble platelet CD40L and CD62P during the preparation process and the storage of apheresis platelet concentrates: Absence of factors related to donors and donations.

Platelet transfusions may be associated with certain adverse effects in recipients, potentially caused by the presence of biological response modifiers contained in the platelet concentrates. The aim of this study is to identify the parameters that reflect platelet activation during both the preparation process and the storage of platelet concentrates. A total of 3,949apheresis platelet concentrate samples were studied with regard to parameters related to the donor as well as to the preparation process and their storage. Key glycoproteins characteristic of platelet activation, i.e. soluble CD40L and CD62P, were quantified in platelet concentrate supernatants on completion of their processing and during storage, using Luminex technology. We observed an increase in soluble factors over time. However, the different parameters studied in connection either with the donors or with the donations, such as (i) donor gender, (ii) donor blood group, (iii) time of collection and (iv) type of apheresis separator, do not seem to have any effect on platelet activation or the release of soluble CD40L and CD62P.