ObjectiveTransfusion-Related Acute Lung Injury （TRALI） is a common fatal transfusion adverse reaction. Major Histocompatibility Complex （MHC） class I is an important factor involved in the pathogenesis of TRALI； however， the role of complement in itspathogenesis has not been fully elucidated. This study aims to explore the role of complement in MHC class I antibody-mediated TRALI， so as to provide a theoretical basis for clinical prevention and treatment. MethodsThis study established a murine model of transfusion-related acute lung injury （TRALI） based on the "two-hit" theory， with lipopolysaccharide （LPS） as the first hit and MHC class I antibody as the second hit. Male Balb/c mice were randomly divided into seven groups （n=5 per group per experiment）： Naive （blank control）， LPS （first hit only）， Isotype （isotype antibody control）， TRALI （model group）， C5aR1 inhi （C5aR1 antagonist intervention）， C5aR2 inhi （C5aR2 antagonist intervention）， and Anti-C5 （anti-complement C5 antibody intervention）. Rectal temperature was monitored after MHC class I antibody injection. After sample collection， the severity of pulmonary edema was assessed by measuring the lung wet-to-dry weight ratio， histological analysis， and immunohistochemistry. Serum and bronchoalveolar lavage fluid were collected to measure cytokine and complement levels. ResultsMice in the TRALI group exhibited a significant decrease in rectal temperature， an increased lung wet-to-dry weight ratio， elevated serum cytokine levels， and markedly heightened complement C5a levels in bronchoalveolar lavage fluid （P＜0.000 1）. Histopathological examination revealed substantial infiltration of inflammatory cells， predominantly neutrophils accompanied by fewer lymphocytes， plasma cells， and monocytes， along with increased deposition of the membrane attack complex C5b-9 in lung tissues. In contrast， mice treated with anti-C5 antibody demonstrated no significant decrease in rectal temperature. The lung wet-to-dry weight ratio in this group showed no statistical difference compared to either the Naive or Isotype control groups （P＞0.05）. Furthermore， these mice displayed reduced serum cytokine levels， a significant attenuation of inflammatory cell infiltration in the lungs， and a 100% survival rate at the 2-hour time point. However， mice administered either the C5aR1 antagonist or the C5aR2 antagonist failed to be protected and subsequently developed TRALI. ConclusionComplement activation， which forms the membrane attack complex C5b-9， plays a critical role in MHC class I antibody-mediated TRALI. Blocking complement C5 activation can effectively prevent the occurrence of TRALI.

Patients with severe trauma require an extremely timely treatment and transfusion plays an irreplaceable role in the emergency treatment of such patients. An increasing number of evidence-based medicinal evidences and clinical practices suggest that patients with severe traumatic bleeding benefit from early transfusion of low-titer group O whole blood or hemostatic resuscitation with red blood cells, plasma and platelet of a balanced ratio. However, the current domestic mode of blood supply cannot fully meet the requirements of timely and effective blood transfusion for emergency treatment of patients with severe trauma in clinical practice. In order to solve the key problems in blood supply and blood transfusion strategies for emergency treatment of severe trauma, Branch of Clinical Transfusion Medicine of Chinese Medical Association, Group for Trauma Emergency Care and Multiple Injuries of Trauma Branch of Chinese Medical Association, Young Scholar Group of Disaster Medicine Branch of Chinese Medical Association organized domestic experts of blood transfusion medicine and trauma treatment to jointly formulate Chinese expert consensus on blood support mode and blood transfusion strategies for emergency treatment of severe trauma patients ( version 2024). Based on the evidence-based medical evidence and Delphi method of expert consultation and voting, 10 recommendations were put forward from two aspects of blood support mode and transfusion strategies, aiming to provide a reference for transfusion resuscitation in the emergency treatment of severe trauma and further improve the success rate of treatment of patients with severe trauma.

【Objective】 To detect the anti-SARS-CoV-2 antibody levels in blood donors in Guangzhou, so as to provide laboratory data support for the collection and clinical use of convalescent plasma. 【Methods】 Anti-SARS-CoV-2 antibodies were measured by ELISA in qualified donors. Among them, 326 donors who gave blood in February 2023 were tested for IgG antibodies, 444 donors were tested for neutralizing antibodies. In July 2023, 398 donors were tested for IgG and IgM. 【Results】 399 of 724 blood samples diluted with normal saline (1∶160) were IgG reactive, with a reactive rate of 55.11%. Chi-square test showed that there was a significant difference in the reactive rate of IgG among samples collected at different times (25.46% in February vs 79.40% in July, χ²=210.74, P<0.01, 95%CI: 7.97, 15.98), but there was no significant difference in the reactive rate between different genders and different age groups. IgM was detected in 5 of 398 blood samples, with a reactive rate of 1.26%. The IgG test results of these five blood donors were all reactive, whereas the nucleic acid test results were negative. Neutralizing antibody was detected in 440 of 444 blood samples, with a reactive rate of 99.10%, and 71.59% of the reactive donors had a neutralizing antibody level of 10 μg/mL or more. 【Conclusion】 Blood donors in Guangzhou have a high level of SARS-CoV-2 antibody, which is sufficient to provide convalescent plasma for clinical treatment.

Blood screening is essential for blood safety. Traditional methods are not very effective in unknown pathogen testing. The blood metagenomic analysis with high-throughput sequencing as the main method is not limited to a particular microbe but detects all microbes in the sample (total genome), which has advantages that traditional methods cannot compare with. With the increasingly maturation of technology and the gradual reduction of cost, metagenomic sequencing has been applied more and more widely. In this paper, the concept and research procedures of metagenomics, the current status and future prospect of metagenomics sequencing technology in the field of blood screening are reviewed.

【Objective】 HLA-DRB1 * 11:01, as a class HLA-Ⅱ gene, was reported to be associated with spontaneous clearance of HCV in Han and Li population. Our study was to investigate the effects of viral selection pressure and CD4+T cell epitope on the natural outcome of HCV infection in HLA-DRB1 * 11:01 positive infected patients. 【Methods】 The positive selection sites and population growth of E1E2 and NS3 genes of common HCV 6a in HLA-DRB1 * 11:01 positive and negative groups in Guangdong were respectively analyzed. The peptide library covering the conserved regions of common HCV genotypes was used to stimulate HCV spontaneous clearance group and chronic infection group using ELISPOT method. Reactive peptides were obtained according to the number of spot-forming cells per well and the frequency of occurrence in different groups. 【Results】 The positive selection sites (PSSs) of E1E2 and NS3 of common HCV 6a in HLA-DRB1 * 11:01 negative group were greater than those in HLA-DRB1 * 11:01 positive group. Furthermore, the number of PPSs in CD4+T cell peptide in HLA-DRB1 * 11:01 negative group were also greater than those in HLA-DRB1 * 11:01 positive group; Both groups of HCV 6a had a population growth in Guangdong, and the expansion trend of HLA-DRB1 * 11:01 negative group was significantly higher than that of HLA-DRB1 * 11 :01 positive group. Compared to HCV chronic infection group, the response rate of HCV spontaneous clearance group to five peptides (C-52 E2691-707, C-119 NS31545-1560, C-134 NS4A1669-1684, C-154 NS4B1912-1927, C-159 NS4B1929-1944) was higher. However, the HCV chronic infection group showed a higher response rate to two of the peptides(C-111 NS31497-1512, C-130 NS31650-1665). When HLA-DRB1 * 11:01 typing was considered, there was no significant difference in HCV-specific immune response generated by PBMCs between HLA-DRB1 * 11:01 positive and HLA-DRB1 * 11:01 negative groups. 【Conclusion】 This study revealed the relationship between viral selection pressure of HLA-DRB1 * 11:01 HCV infected persons and CD4+T cell antigen epitopes. At the same time, CD4+ T cell antigen epitopes of HCV pan-genotype were obtained, providing basic data for the development of T cell vaccine suitable for HCV pan-genotype.

Antibodies against human CD36 are responsible for several immune-mediated disorders. The detection of anti-CD36 antibodies using the standard monoclonal antibody (mAb) immobilization of platelet antigens (MAIPA) assay is hampered by a high frequency of false-negative results, most likely due to competitive inhibition of the mAb used as the capture antibody. We generated a panel of mouse mAbs against CD36 and seven hybridomas (GZ-3, GZ-13, GZ-70, GZ-143, GZ-413, GZ-507, and GZ-608), which were selected for MAIPA assays, as they reacted with mouse and human CD36. Fourteen anti-CD36 sera were assayed; all of which showed a positive reaction in a PakPlus (Immucor GTI Diagnostics, Inc., Waukesha, WI, USA) ELISA-based screening (optical density: 0.257–2.292). When the reference anti-CD36 mAb FA6-152 was used in the MAIPA assay, only 6/14 (42.9%) sera displayed a positive reaction. In contrast, anti-CD36 antibodies were detected in 13/14 (92.9%) sera when GZ-70 and GZ-608 mAbs were used. This significant improvement resulted in the identification of anti-CD36 antibodies by an antigen capture assay. Since patient’s platelets possibly carrying rare native antigens are used, this method will facilitate the identification of new platelet antibodies against CD36 that are involved in immune-mediated thrombocytopenia and other diseases, such as transfusion-related acute lung injury.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the pathogen that causes novel coronavirus pneumonia. The SARS-CoV-2 mainly transmits through respiratory tract. However, RNA of this virus can be detected in blood samples of some infected cases. This paper herein reviewed the risk of transfusion transmission of SARS-CoV-2 and relevant preventive measures. The impact of SARS-CoV-2 endemic on blood supply and the corresponding strategy were also discussed in this article.

【Objective】 To discuss the influence of apheresis platelets donation mode transformation, from walk-in to appointment, on apheresis platelets donation, donor retention and donation service quality. 【Methods】 The comparative research method is used to compare the number of apheresis platelets donors, blood donation units, rate of first-time blood donation, rate of repeated blood donation, conversion rate of fixed whole blood donors and satisfaction rate before and after the transformation of donation model. Questionnaires were randomly distributed to apheresis platelets blood donors before and after the transformation to study the evaluation of appointment mode. 【Results】 In comparison with walk-in mode, the number of blood donors after adopting the appointment mode was 30 193, with 41.93% (8 920/21 273) increase; number of blood donations was 119 143, with 93.66% (57 622/61 521) increase; platelet donation was 212 717 treatment units, with 103.12% (107 990/104 727) increase; rate of repeated blood donation was 53.56% (16 172/30 193), with 15.43% increase; the number of first-time donors was 15 949, with 57.93% (5 850/10 099) increase; the conversion rate of fixed whole-blood donors was 37.86% (6 039/15 949), with 8.84% increasement; the satisfaction of appointment mode reached 99.81%, with significantly improved satisfaction with blood donation environment and waiting time. 【Conclusion】 The appointment mode of apheresis platelet donation has a promoting role in the increase of apheresis platelets donation, the improvement of solid blood donors and the quality of apheresis platelets donation services.

【Objective】 To study the CD4 T cell epitopes in Core and NS3 protein of genotype 1(GT1) and 6(GT6) of hepatitis C virus(HCV). 【Methods】 A total of 298 overlapping peptides(16-mer) spanning Core and NS3 protein of GT1 and GT6 HCV were synthesized. Peripheral blood mononuclear cells(PBMCs) from 17 HCV+ and 7 healthy blood donors were stimulated by peptide pools, followed by evaluating T cell response by IFN-γ ELISPOT, by which 21 peptides with positive results were found. These peptides were further applied to individually stimulate 20 HCV+ and 18 healthy PBMCs. The differences of responsive frequencies to the 21 positive peptides between the two study groups were compared. 【Results】 Pooled and individual peptide stimulation tests showed that HCV+ PBMCs were responsive to the stimulation of 5 peptides(GT1 NS31273-1288 and NS31315-1330; GT6 NS31033-1048, NS31087-1102 and NS31351-1366), with a responsive frequency ranging 18.9%-27.0%. In contrast, healthy PBMCs were not or low responsive(0%-4.0%) to these five peptides. The responsive frequencies were statistically different between the two groups(P<0.05). No reported epitopes in IEDB were found identical with these 5 peptides via sequence alignment. 【Conclusion】 Our study identified novel CD4 T cell epitopes in NS3 protein of GT1 and GT6 HCV, which has potential application value for the research and development of HCV vaccine.

【Objective】 To learn the situation of the evolution process of HCV virus population and the selection pressure of HCV NS5B in intravenous drug users (IDUs) in Guangdong. 【Methods】 141 blood samples from hepatitis C virus (HCV) RNA-positive blood donors and 58 from HCV patients in Guangdong were randomly collected for HCV NS5B sequence amplification, combined with HCV NS5B sequences from blood donors and IDUs obtained by sequencing previously(between 2009 and 2011). Homology analysis was performed by Molecular Evolutionary Genetics Analysis (MEGA) software, evolutionary analysis were performed by Bayesian Evolutionary Analysis Sampling Trees (BEAST) software package. Selection pressure analysis was performed on sequences isolated from IDUs by Datamonkey online software package with Mixed Effects Model Evolution (MEME) method, and the population expansion of species were analyzed using Tajima and Fu neutrality test by Arlequin software. 【Results】 The comparison results of internal homology among different subtypes of IDUs in this group were as follows : HCV-3b had the highest homology (97%), followed by HCV-3a (96%), HCV-6a (95%) and HCV-1b (94%); HCV evolution rate analysis showed that HCV-1b had the fastest evolution rate [2.17E-03 substitutions/site/year (y/y/y)], followed by HCV-3b (2.12E-0 y/y/y), HCV-3a (1.58E-03 y/y/y) and HCV-6a (1.28E-03 y/y/y). The analysis on effective population of HCV: 1980~1990 was rapid growth period for HCV-6a, 1990~1995 period for HCV-1b, and 2000~2007 period for HCV-3a. HCV population genetic characteristics was as follows: HCV-1b, 3a, 3b and 6a experienced population expansion, among which 3a and 3b were the most obvious. As to the analysis of HCV selection pressure, two positive selection sites (235 and 243)were found in the 339 nucleotide fragment of the NS5B sequence in injecting drug users, but mutation only occurred at position 316 [mutation rate 1.24% (14/1 130)] among 5 direct antiviral drug (DAA) sites in this gene. 【Conclusion】 The evolution of HCV-3b in Guangdong has showed an obvious trend of population expansion, with a high proportion and homology especially in the local IDUs. HCV-3b should be the focus of HCV prevention and control in this region. Given that the positively selected sites of the HCV NS5B gene region of IDUs in Guangdong are non-DAA binding sites, DAA is expected to demonstrate a good effect on these patients.