【Objective】 To investigate the effect of phenotypes of Duffy blood group on chemokine storage and chemokine scavenging function of erythrocytes. 【Methods】 Twenty-four erythrocyte samples were collected and tested Duffy blood phenotype using the anti-human globulin method, and erythrocyte CCL2, CCL5, CXCL8, and CCL11 content and their chemokine scavenging function using ELISA. The expression of Duffy antigens on erythrocytes was detected using a flow analyzer. 【Results】 The difference in CCL2 content(41.1±14.7 pg/mL vs 63.1±20.8 pg/mL)of erythrocyte lysate between Fy(a+b-) and Fy(a+b+) phenotype was statistically significant (P<0.05), however, the difference in the content of CCL5(794.5±320.1 pg/mL vs 846.9±359.4 pg/mL), CXCL8(59.5±34.2 pg/mL vs 49.1± 11.9 pg/mL), and CCL11(109.1±25.1 pg/mL vs 158.6 ±56.0 pg/mL) were not statistically significant (P>0.05).The difference in the scavenging function of CCL2(1471±202.1 pg/mL vs 1860±267.5 pg/mL)and CCL5 (848.5±461.7 pg/mL vs 1797±546.1pg/mL) between Fy(a+b-) and Fy(a+b+) phenotype were statistically significant (P<0.05), however, for CXCL8(1851±180.7 pg/mL vs 1 862± 248.3 pg/mL) and CCL11(691.0±125.7 pg/mL vs 781.7 ±293.8 pg/mL) scavenging function the difference were not statistically significant (P>0.05).The difference in Duffy antigen expression (mean fluorescent intensity:105.3±20.45 vs 111.9±18.30)on erythrocytes between Fy(a+b-) and Fy(a+b+) phenotype was not statistically significant (P>0.05). 【Conclusion】 The Fy(a+b+) and Fy(a+b-) phenotypes of the Duffy blood group can affect the chemokine storage and scavenging function of erythrocytes. Fy(a+b+) phenotypes are able to store more chemokines and have a stronger chemokine scavenging function than Fy(a+b-) phenotypes.

Objective: To investigate prevalence of hepatitis E virus (HEV) infection among voluntary blood donors in Dalian and provide evidence for enhancing blood screening strategies. Methods: A total of 3 277 blood donor samples collected between December 2023 and February 2024 at Dalian Blood Center underwent routine blood screening (ALT, HBsAg, anti-HCV, HIV Ag/Ab, anti-TP, and HBV/HCV/HIV NAT). Subsequently, HEV antigen (Ag) was detected using chemiluminescence immunoassay (CLIA). HEV-Ag reactive samples were further tested for HEV RNA, IgM and IgG antibodies. Blood donors with repeated reactive HEV Ag results were followed up to clarify the status of infection. Results: Among the 3 277 blood donor samples, 6 (0.18%) were repeatedly reactive for HEV Ag. However, supplemental testing for HEV RNA, anti-HEV IgM, and anti-HEV IgG on these samples yielded non-reactive results. One of these six blood donors was successfully followed up. On day 218 after the initial detection of HEV Ag reactivity, HEV Ag, HEV RNA, HEV IgM and IgG antibody were found to be non-reactive. Conclusion: The reaction rate for HEV antigen screening among voluntary blood donors in Dalian is low. CLIA method for detecting HEV antigen is easy to operate and cost-effective, but demonstrates some false reactivity. Improving the specificity of the assay and combining it with nucleic acid testing (NAT) would be valuable for implementing a selective HEV screening strategy for blood donors.

【Objective】 To establish a novel preparation method of cryoprecipitate coagulation factor from overcooled liquid-state plasma. 【Methods】 The fresh liquid plasma was kept at -11℃ to -13℃ for a period of time. It can remain in the liquid state with some coagulation factors generated due to supercooling. Then cryoprecipitate can be obtained from the liquid plasma by siphon method. 【Results】 The average fibrinogen content yielded in cryoprecipitate, prepared from 50 samples of 16-hour-stored fresh liquid plasma, was (186.02±22.72) mg, with the average recovery rate of (37.51±7.42) %, and the average content of coagulation FⅧ was (104.66±22.88) IU, with the average recovery rate of (46.62±5.58) %. 【Conclusion】 The cryoprecipitate coagulation factors could be obtained not only from fresh frozen-thawed plasma, but also from overcooled liquid plasma which is simple and stable, also meets the requirements of relative standards.

【Objective】 To analyze the environmental monitoring results of NAT laboratory from 2016 to 2019 and evaluate the influence of environmental quality on blood screening. 【Methods】 Monthly/Quarterly environmental monitoring was carried out in NAT laboratory regularly by means of air deposition and surface wiping. The monitoring results were statistically analyzed and comprehensively evaluated in combination with the pool/multiplexNATreactiverate and discriminatory/resolutionrate. 【Results】 A total of 48 batches of environmental monitoring tests were conducted from 2016 to 2019, 11 (25 reactive sites) were unqualified, including 15 reactive sites (60%) as the hallway doorknob or access control, which were the public areas shared with serology laboratory, and these sites were not reactive for 6 consecutive months after intensive cleaning and disinfection. In Nov.2017, the air deposition in biosafety cabinet and surface wiping of Cobas s 201 were reactive, and the restwere the doorknobs. Pearson correlation analysis showed that there was no correlation between the positive rate of environmental monitoring and the detection amount, the pool/ multiplex NAT reactive rate and discriminatory/resolution rate. 【Conclusion】 The accidental environmental pollution in the laboratory is not related to the detection amount and positive rate, indicating that the cleaning and anti-pollution measures are timely and effective to ensure the accuracy and reliability of the screen results. NAT laboratory should gradually establish and improve the environmental monitoring system according to the layout and environment so that the environmental quality meets the testing conditions.

【Objective】 To evaluate the role of anti-HBc detection in current blood screening strategy by the follow-up of repeated donors with antibody to hepatitis B virus core antigen. 【Methods】 Plasma samples were collected randomly from Dalian Blood Center. to test anti-HBc(dual reagents) and anti-HBs via ELISA. The re-donation of eligible donors who were anti-HBc+ and donors reactive to HBV detection were followed up. 【Results】 A total of 1 291 plasma samples were collected randomly from May 2017 to March 2018, among which 405 samples(31.4%)were anti-HBc+. The median age of anti-HBc+ group was observed much higher than that of anti-HBc-group (39 vs 31 years old) (P<0.05), but no significant difference was noticed in gender nor the proportion of first-time/repeated blood donors (P>0.05). Among the 405 anti-HBc+ donors, 3 donors were OBI (0.7%), of which one was screened out in second donation. No HBV DNA was detected out in 3 OBI cases. 【Conclusion】 Although anti-HBc detection is not suitable in blood screening currently, it is of great value in the assessment of blood donor re-entry for HBV reactive donors in blood screening due to the high anti-HBc prevalence among blood donors.

Objective　To investigate the development of the guinea pig's eye during the stage of embryo.Method　The guncotton grafts of the guinea pig's skull was observed on the 19th ,24th,28th,35th,40th,43th and the 45th day of embryo.Results　The optic vesicle and lens plate developed on the 19th day in embryo.The optic cup and lens fovea could be found on the 24th day.The eye of embryo of the guinea pig had formed on the 28th day.Conclusion　The results should be used for progressive study of the development of the eyes of embryo.

【Objective】 To investigate the serological and molecular characteristics of HBsAg+ /HBV DNA non-reactive (NR) infections. 【Methods】 Samples tested as HBsAg+ and HBV DNA NR were confirmed by individual NAT repeat testing, viral particle concentration by PEG precipitation combined with in-house nested PCR and real-time quantitative PCR, anti-HBc testing, and HBsAg quantification. HBV sequences were compared with those from donors with chronic and occult infection as controls. 【Results】 A total of 792 195 samples were screened between January 2011 and December 2020, of which 53 (1: 14 947) were confirmed HBsAg+ /HBV DNA NR. HBV DNA was detected further in five (9.4%) samples; three S sequences and four Pre Core/Core sequences were obtained. Unique amino acid substitutions (P130T, P135Q/S, R151Q, G153S and S155F) were found in the Core protein that may affect virus packaging and replication. 【Conclusion】 Extremely low HBV DNA level was detected in plasmas of HBsAg+ /HBV DNA NR donors. Barely detectable HBV DNA might be associated with unusual mutations in the Pre Core/Core protein affecting viral replication. More sensitive HBV DNA and/or HBsAg assays may be considered to further reduce the potential HBV transfusion-transmission residual risk.

【Objective】 To establish a reasonable and effective blood screening strategy for Hepatitis C virus (HCV), so as to reduce the risk of blood transfusion transmission, ensure blood safety and improve the quality of blood screening. 【Methods】 In order to evaluate HCV screening strategies comprehensively, the unqualified blood donations due to anti-HCV alone positivity in Dalian from 2017 to 2021 was tracked, with combined detection methods of electro-chemiluminescence immunoassay (ECLIA) and HCV-RNA nucleic acid test (NAT). 【Results】 A total of 851 (0.20%) unqualified donations due to anti-HCV alone positivity were screened from 2017 to 2021, with a decreasing trend in both numbers and rate. Among them, the unqualified rate of samples with anti-HCV reactivity in both dural-ELISA-reagent and NAT decreased significantly (P<0.05). A total of 117(0.028%) samples were anti-HCV reactive in dural-ELISA-reagent but nonreactive in NAT; 664 reactive in one-ELISA-reagent, with 70(10.54%) in Reagent Ⅰ and 594(89.46%) in Reagent Ⅱ; 122 (35.88%) out of 340 donations were reactive in ECLIA. Among the 28 participants in the follow-up test, 15 still were reactive in ELISA and 2 reactive in ECLIA. 【Conclusion】 Although the unqualified rate of HCV is decreasing, serological screening of anti-HCV is still an important method for ensuring blood safety, and its complementarity with HCV-RNA NAT should be evaluated. As a new serological assay, ECLIA has high sensitivity and specificity. Miss detection may occur if only one ELISA reagent is adopted for anti-HCV detection. Appropriate ELISA and NAT system for HCV screening should be reasonably chosen, and HCV screening strategy should be developed and adjusted according to the local conditions.

【Objective】 To investigate the correlation between human platelet antigens (HPA) polymorphisms and platelet parameters. 【Methods】 The HPA-2, HPA-3, HPA-5 and HPA-15 genotypes of 139 healthy Chinese Han individuals were detected using TaqMan-MGB probe real-time PCR, while platelet parameters including platelet count (PLT), mean platelet volume (MPV), platelet distribution width (PDW) and platelet-large cell ratio (P-LCR) were measured using hematology cell analyzer. 【Results】 The PLT was significantly lower in the individuals with HPA-2aa genotype compared to those with HPA-2ab [(234.35±50.10)×10³/μL vs (269.58±41.66)×10³/μL, P<0.05], while the PLT was significantly higher in individuals with HPA-5aa and HPA-15aa genotypes compared to those with HPA-5ab and HPA-15ab/bb [HPA-5: (239.36±49.81)×10³/μL vs (200.29±48.02)×10³/μL; HPA-15: (251.00±58.41)×10³/μL vs (231.29±45.20)×10³/μL, P<0.05], respectively. The MPV, PDW and P-LCR were significantly lower in individuals with HPA-5aa genotype compared to those with HPA-5ab [mpv: (10.01±0.72)fL vs (10.94±1.01)fL; PDV: (11.94%±1.35%) vs (14.25%±2.78%); P-LCR: (25.32%±5.03%) vs (31.73%±6.39%), P<0.05], but did not differ among the HPA-2 and HPA-15 genotypes. Besides, no significant differences in platelet parameters of individuals with HPA-3aa and HPA-3ab/bb genotypes were notable(P>0.05). HPA-2, -5 and -15 polymorphisms were identified as independent factors for platelet count, and HPA-5 polymorphism was an independent factor for platelet volume, revealed by multiple linear regression analysis. 【Conclusion】 HPA-2, -5 and -15 polymorphisms are correlated with platelet count, and HPA-5 polymorphism is correlated with platelet volume.

【Objective】 To determine the effect of storage time on the chemokine storage and chemokine scavenging function of erythrocyte atypical chemokine receptor 1(ACKR1). 【Methods】 Samples from six bags of red blood cells product, split into two gruoups(10 mL each), were stored in a refrigerator and sampled on day 5 and day 25 during storage, respectively, to measure the concentrations of CCL5, CXCL8 and CCL11 and the ACKR1 chemokine scavenging function of erythrocytes. In addition, 42 erythrocyte products(1 mL each), stored for 5 to 25 days, were sampled to measure the expression of ACKR1 and the concentrations of chemokines CCL5, CXCL8 and CCL11 on the erythrocyte membrane. 【Results】 Compared with RBCs stored for 5 days, no difference in the concentration of CCL5(467.7±250.2 pg/mL vs 586.9±209.5pg/mL, P>0.05) and CCL11(122.2±30.3pg/mL vs 125.5 ±32.7pg/mL, P>0.05)were noticed in erythrocyte lysates stored for 25 days, but the concentrations of CXCL8 decreased significantly(42.4±5.3pg/mL vs 24.3± 5.9pg/mL, P<0.05), and the scavenging ability of erythrocyte ACKR1 to chemokines CCL5(2 634.0±730.2pg/mL vs 453.8±257.4 pg/mL, P<0.05), CXCL8(1 117.0±236.6pg/mL vs 306.2±28.3pg/mL, P<0.05) and CCL11 decreased(1 278.0 ±164.5pg/mL vs 467.2 ±50.9pg/mL, P<0.05). Chemokines CCL5, CXCL8 and CCL11 had not been detected on the surface of erythrocyte membrane. There was no significant change in the expression of ACKR1 on the surface of erythrocytes from day 5 to day 25 (P>0.05). 【Conclusion】 Erythrocytes are the main places for storing ACKR1 binding chemokines. During the storage, the chemokine scavenging of erythrocyte ACKR1 and some intracellular the ACKR1 binding chemokines are reduced.