Currently, there are insufficient sources of platelets for clinical transfusion, and there are risks of alloimmune reactions and transfusion-transmitted infections (TTI) after transfusion. In recent years, platelets derived from human induced pluripotent stem cells (hiPSCs) have become one of the hottest research topics in the transfusion community, and studies have shown that they have the potential to address the limitations of platelet transfusion and alleviate the conflict between platelet supply and demand in clinical settings. However, the efficiency of hiPSCs in producing functional platelets in vitro is still low, and the yield and quality are still far below clinical transfusion standards. In this review, the basis and applications related to hiPSCs-derived platelets, studies related to human leukocyte antigen (HLA) gene-silenced hiPSC-derived platelets, and challenges faced by hiPSCs-derived platelet products were reviewed, providing references for in-depth research and future clinical applications of hiPSCs-derived platelets.

Objective To investigate the morphological and proteomic differences in exosomes(EXOs)during the stor-age of leukocyte-free apheresis platelets(LFA-Plt),evaluate the quality of platelets in storage and predict the function of EXOs at different storage periods.Methods EXOs were isolated by ultracentrifugation,then the morphological observation was performed by electron microscope.Particle size analysis and WB protein index detection were performed.4D Label-free quantitative proteomics technology was used to perform quantitative and bioinformatics analysis on identified proteins.Protein differential analysis on the LFA-Plt EXO between group day 3 and day 5 was performed,and GO function and KEGG path-way enrichment analysis on differential proteins was conducted.Results Cup shaped,CD9/TSG101 enriched and Calnexin(-)EXO was successfully obtained.The particle size(nm)of LFA-Plt EXO for day 3 and day 5 were(82.2±19.6)and(83.4±19.4)respectively,and the protein concentration(μ g/uL)were(0.55±0.13)and(0.51±0.08)respectively,with no statistically significant difference between two groups(P＞0.05).1 504 proteins were identified in all samples.GO func-tional enrichment analysis showed that the LFA-Plt EXO proteins were mainly concentrated in the cell membrane,extracel-lular domain and proteasome core complex,and were related to the binding ability of proteins,ATP,calcium ions and GTP,and mainly participated in processes such as redox,protein hydrolysis and signal transduction.KEGG functional annotation showed that the EXO proteins mainly participated in material transportation and catabolism,genetic information processing,and were closely related to human tumors and viral bacterial infections,affecting the metabolism of human immune system.Compared with day 3,day 5 EXO showed significant up-regulation in 16 proteins.The GO enrichment analysis showed that 16 upregulated proteins were mainly associated with adenosine homocysteine activity and 6-phosphofructose kinase activity,and were mainly involved in the metabolism of organic nitrogen compound.KEGG enrichment pathway analysis showed that the most important function of upregulated proteins was participating in signaling pathway for oocyte maturation mediated by progesterone.Conclusion Under the preparation and storage conditions of LFA-Plt in our center,platelet quality can be relatively stable.The functions of EXO proteins varies with different storage periods,which may affect the effectiveness of platelet transfusion.

【Objective】 To analyze the serological markers and RNA prevalence of HEV infection in Chinese voluntary blood donors in different regions of China, so as to provide basis for the necessity of HEV screening and the formulation of screening strategies for voluntary blood donors. 【Methods】 Databases such as CNKI, Wanfang medicine and PubMed were searched for eligible literature, and the literature data meeting the inclusion criteria were extracted for meta-analysis using R4.1.3 software. 【Results】 A total of 26 studies were included, involving 97 928, 117 831 and 82 673 cases, respectively, for anti-HEV IgG, anti-HEV IgM and HEV RNA. The pooled estimated prevalence of anti-HEV IgG, anti-HEV IgM and HEV RNA among Chinese voluntary blood donors was 23.0% [95% CI (18%, 29%)] vs 1.13% [95% CI (0.94%, 1.36%)] vs 0.028%[95%CI(0.006%, 0.059%)], and there were significant differences among different cities and regions. 【Conclusion】 The past infection rate of HEV among voluntary blood donors in China was somewhat high and with significant regional differences. The current infection rate was relatively low and had decreased compared with that in the past decade, but there was still residual risk of blood transfusion. It is necessary to pay more attention to blood HEV screening of voluntary blood donors.

【Objective】 To evaluate the laboratory's NAT ability by analyzing the feedback reports of nucleic acid test (NAT) results of external quality assessment (EQA) of National Center for Clinic Laboratories (NCCL), so as to improve the laboratory management details and ensure blood safety. 【Methods】 The data of NCCL NAT EQA of blood screening laboratory of Tianjin Blood Center (a total of five occasions from Jan 2019 to Jun 2021) were statistically analyzed. 【Results】 From Jan 2019 to Jun 2021, the laboratory participated in EQA for five times and all the results were qualified. The test results of NAT EQA HIV RNA/HCV RNA/HBV DNA detected by R1, R2 and R4 were consistent with the reference results. R3 showed false positive results (CT value 40.46) in the single donation detection of sample No.1925 in HCV RNA. Unreported data of the laboratory was that in the first EQA in 2021, the R4 showed false positive results (CT value 35.8) in in the single donation detection of sample No.2113 in HIV RNA. 【Conclusion】 The performance of each NAT screening system in our laboratory is relatively stable except occasional false positive results influenced by every factor. Potential problems can be found and continuously improved by assaying EQA reports and the extended experimental results of EQA samples to further improve the detection ability.