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【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.
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【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.
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【Objective】 To investigate the CMV-IgG positive yeild among blood donors in Guangzhou and explore the differences in the efficacy of three test reagents, aimed at improving blood safety and service capacity of blood centers. 【Methods】 A total of 630 blood samples from eligible blood donors from July to October 2020 in our center were randomly selected and screened for CMV-IgG by one ELISA reagent.Among them, 180 samples were tested in parallel using three reagents (two ELISA reagents and one ECLIA reagent), and those tested negative were conducted quantitative CMV-DNA detection.The test results of different reagents were compared and analyzed. 【Results】 Out of the 630 samples, a total of 598 positive samples were screened out, including 180 samples yielded by three reagents, 171 and 175 by the two ELISA reagents, respectively, and 175 by ECLIA.The results given by three reagents were consistent (Kappa>0.4), and no significant difference in the positive yeild by three reagents was found.In the 180 samples, 11 were negative, among which 3, 2 and 6 samples were negative by all three reagents, two reagents and one reagent (ELISA), respectively.All the 11 samples were tested negative for CMV-DNA. 【Conclusion】 The yeild of positive CMV-IgG in blood donors was 94.9% (598/630), suggesting a high prevalence of CMV in Guangzhou. CMV serologically negative blood should be considered when providing blood products to immunocompromised patients to improve the safety of recipients.The detection results of ELISA reagents and ECLIA reagent for CMV- IgG are consistent, but ECLIA reagent has better detection efficacy.
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【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.
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【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.
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【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.
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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.
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【Objective】 To investigate the correlation of peripheral myeloid-derived suppressor cells (MDSC) with hepatitis c virus (HCV) infection. 【Methods】 109 voluntary blood donors who donated blood during February 2018 to September 2020 at Guangzhou Blood Center were recruited in this study. They were assigned to chronic hepatitis c (CHC) group (n=48), spontaneous clearance (SC) group (n=29) and healthy donors (control) group (n=32) according to the results of anti-HCV and HCV RNA tests. Blood samples were drawn from the participants and peripheral blood mononuclear cells (PBMC) were freshly isolated, followed by staining with fluorescently-labeled antibody against cell surface markers of MDSC, which were then applied to the detection of monocytic- (M) and polymorphonuclear (PMN)-MDSC by flow cytometry. Parameters for liver function including alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyl transpeptidase (GGT), total bilirubin (TBIL) and direct bilirubin (DBIL) were also measured. One-way ANOVA tests were applied to compare the differences of M- and PMN-MDSC and liver function between three study groups. For pairwise comparisons, P values were adjusted for multiple comparisons by Bonferroni correction (Pc). 【Results】 The frequencies of M-MDSC (%) in CHC, SC and HC were 1.39±0.86, 0.85±0.63 and 0.57±0.23, respectively (P0.05). In addition, AST (34.4±19.2 vs 23.0±7.78 U/L) and GGT (40.8±31.4 vs 22.3±7.40 U/L) level were higher in CHC compared with control (Pc<0.05 and Pc<0.01, respectively). 【Conclusion】 The level of peripheral M-MDSC was significantly elevated in chronic HCV infected donors, which would related to the progression of chronicity after HCV infection.
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Objective:To explore the association between interleukin(IL)-28B single nucleotide polymorphisms and natural outcome of hepatitis C virus.Methods:The IL-28B rs12979860 locus was genotyped in 266 HCV infected volunteer blood donors(107 spontaneous cleared and 159 chronic infection) and 97 healthy controls using Sanger sequencing assay.The difference in rs12979860 genotypes and allele frequencies between the six groups(107 spontaneous cleared and 159 chronic infection,266 HCV infection and 97 healthy controls,159 chronic infection and 97 healthy controls) were analyzed by statistics.Results:159 HCV chronic infection,107 spontaneous cleared and 97 healthy controls,were shown more CC genotype,accounting for 83.6%,95.3%and 86.6%,respectively, while the CT genotype accounted for 16.4%,4.7%and 13.4%respectively.No TT genotype was found.The CC/CT genotype was not significant difference between HCV infection and healthy controls,chronic infection and healthy controls(χ2=0.204,P=0.652;χ2=0.406,P=0.524),but between chronic infections and spontaneous clearance had statistically significant(χ2=8.474,P=0.004),the frequence of C allele in spontaneous cleared was higher than HCV chronic infection(χ2=7.949,P=0.005).Conclusion: The gene polymorphism of IL-28B rs12979860 is not related to HCV susceptibility,but there are differences in chronic infection and spontaneous cleared,showing the C allelic in favor of HCV spontaneous cleaed.
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Objective To study the polymorphism of human platelet antigens among unrelated Guangzhou blood donors with PCR-SSP,in order to provide basic data for population studies and clinical transfusion practice.Methods Blood samples from 706 unrelated blood donors in Guangzhou were genotyped for each of the HPA1—6,15 systems by PCR-SSP.Gene frequencies and genotype frequencies were analyzed by statistical methods.Results HPA-3 and-15 had the greatest heterozygosity with a gene frequency of 0.2918,0.4830,0.2252 for HPA-3a/a,HPA-3a/b,HPA-3b/b,and 0.2691,0.5170,0.2139 for HPA-15a/a,HPA-15a/b,HPA-15b/b.The a/a homozygosity was predominant in HPA-1,-2,-4,-5,with a frequency ranged from 0.9583 to 0.9993,while HPA b/b was not found among them.The frequency of HPA-lb and HPA-4b was very low,which was 0.0028 and 0.0007,respectively.In our study,HPA-1 frequency was significantly different from that of the north Chinese,English,and American Indian(P
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Objective Study on producing human monoclonal antibodies against Rhesus (D) antigen that was suitable for use as blood group typing reagent. Methods B lymphocytes from a Rh negative woman, which can produce anti D antibodies were transformed by Epstein Barr virus(EBV). Antibody secreting cells were enriched by RhD + group O erythrocytes and cloned by limited dilute method. By using one step emzymatic method on microplates, one thousand normal blood donors with a common Rh phenotype were tested with the supernatant of cell culture medium as well as a polyclonal human anti D and a commercial monoclonal anti D serum. Results Three human B lymphocyte lines secreting monoclonal antibodies to Rh (D) were established. One of them produced lgM antibody. The titer of the monoclonal antibodies was 64～128. Study on 1000 blood donors, the results did not show any discrepancy among the three different anti Rh(D) serum. Conclusion These monoclonal antibodies against D antigen could be used in Rh(D) typing.
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Objective To observe the difference between the bone marrow and peripheral blood engraftment evidence after allogeneic haemopoietic stem cell transplantation(Allo-HSCT) using PCR-STR. Methods DNA from peripheral blood or bone marrow of donors and recipients in different phases were extracted,and 16 STR loci with high polymorphism were amplified by PCR.Separation of the PCR products and fluorescence detection were performed by ABIprism 3100 Genetic Analyzer with capillary electrophoresis.Results The 16 patients included in the study had different levels of engraftment.Twelve patients displayed complete chimerism,while 5 patients showed mixed chimerism.One patient was keeping continuance of remission.The decrease of donor DNA amounts in mixed chimerism was earlier in bone marrow than that in peripheral blood(P
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AIM: To amplify from leader peptide region an d obtain human monoclonal anti-D variable region gene with high specificity and affinity, and analyze the nucleotide and deduced amino acid sequences.ME THODS: The total RNA was extracted from an Epstein-Barr-virus-transforme d cell line secreting monoclonal anti- (rhesus D) antibody. The leader region pri mers containing a ribosome recognition site were designed. By using PCR method, the cDNA of human anti-(rhesus D) antibody (IgM ?) variable region gene was amp lified. Cloning and subsequent sequence analysis of the variable region gene was performed. The deduced amino acid sequence was also compared and analyzed with previ ously published sequences.RESULTS: A band of approximate 440 and 410 base pairs were amplified using heavy chain primers and light chain primer s, respectively. Sequence analysis indicated that the deduced amino acid sequenc e w as in agreement with the characterization of the amino acid present in the human Ig variable region. CONCLUSION: The cloning and sequencing of a human anti- (Rhesus D) antibody variable region cDNA will make benefits for pro duction of recombinant anti-(Rhesus D) antibody and prevention of Rh haemolytic disease in newborns.
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Objective:To characterize the allele frequencies and its polymorphisms of human platelet antigen (HPA) in Guangzhou population.Methods:A total of 500 samples from healthy voluntary platelet donors in Guangzhou were genotyped for HPA-1 to-17 by PCR-SSP.Results:HPA-1a to-17a alleles were found in each of the samples;The gene frequencies of HPA-1a to-17a were 99.8%,99.85%,56.3%,99.9%,98.8%,98.6%,100%,100%,100%,100%,100%,100%,100%,100%,55.1%,and 100%,100% respectively.The gene frequencies of HPA-1b to-6b and-15b alleles were 0.2%,0.15%,43.7%,0.1%,1.2%,1.4% and 44.9% respectively;HPA-7b to-14b and-16b-17b were not detected.In summary Guangzhou population displayed higher frequency of HPA-1a to-17a and HPA-3b,-15b.Compared with those of other Han populations in China,HPA frequency of Guangzhou people was significantly different from that of Beijing;Compared to that of the European,American,English and Egyptians,HPA frequency was different significantly.While HPA frequency was different from those of Japanese and Thais.This study for the first time investigated the assortment of HPA genes and its frequency,there were 40 assortments in Guangzhou population,only 5 assortment of HPA gene frequencies more than 10%,35 assortment of HPA gene frequencies less than 9%.Conclusion:HPA distribution in Guangzhou population appears to have local characteristics.This study confirms the ethnic and original difference of HPA.The allele frequencies and its polymorphisms of HPA in Han population are shown North-South differences.Races and countries outside Asia are also shown differences.The basic information provided by this study of the HPA system polymorphisms is useful to guide the design of the local HPA genotype database of volunteer platelet donors.It's also useful to avoid the PTR,and the HPA related clinical research.
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AIM: To investigate the expression of B lymphocyte stimulator(BLyS) and CD38 molecules on peripheral blood lymphocytes of patients with systemic lupus erythematosus(SLE). METHODS: Twenty-two patients with SLE and fourteen healthy subjects entered the study. Isolated peripheral blood lymphocyte were stained for the lymphocyte surface markers BLyS, CD19, and CD38, and then was measured by flow cytometry(FACS). RESULTS: BLyS + lymphocytes, CD19 + lymphocytes, and CD19 +CD38 + lymphocytes were increased significantly in patients with SLE( P
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Objective To establish eight human platelet antigen systems and HLA-Ⅰ antigen donor bank,and to determine the gene frequencies of human platelet antigen(HPA) and HLA-Ⅰin Guangzhou area.Methods A total of 805 blood samples from Chinese Han voluntary platelet donors were included in this study.PCR-SSP was used to detect single-nucleotide polymorphism in HPA systems.Luminex-SSO was used to detect the HLA-Ⅰantigens.Results The distribution of HPA 1,2,3,4,5,6,9,15 was in Hardy-Weiberg equilibrium among study subjects.Allele frequencies of 0.998 and 0.002 were observed for HPA 1a and 1b,0.952 and 0.048 for HPA 2a and 2b,0.553 and 0.447 for HPA 3a and 3b,0.999 and 0.001 for HPA 4a and 4b,0.976 and 0.024 for HPA 5a and 5b,0.982 and 0.018 for HPA 6a and 6b,1 and 0 for HPA 9a and 9b,0.518 and 0.481 for HPA 15a and 15b.The high frequency HLA-Ⅰ alleles were A*02,0.286;A*24,0.162;A*11,0.323;B*46,0.147;B*75,0.100;C*01,0.177;C*03,0.289;C*07,0.179.Conclusions This study confirmed the ethnic and territorial difference of HPA and HLA-Ⅰ.The establishment of HPA and HLA-Ⅰ matched plateletpheresis donor registry is helpful in the improvement in platelet transfusion.
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AIM: To establish human lymphocyte cell line secreting monoclonal antibody against Rhesus(D) antigen and analyse the nucleotide and deduced amino acid sequences of a human monoclonal anti-D Fab fragment. METHODS: By using PCR method, the cDNA of human anti-(Rhesus D) antibody(lgM ?)Fab fragment was amplified from an Epstein- Barr-virus-transformed cell line. Cloning and subsequent sequence analysis of the Fab fragment was performed. The deduced amino acid sequence was compared and analysed with previously published sequences. RESULTS : A band of approximate 700 and 650 base pairs was amplified using lgM heavy chain primers and ? light chain primers, respectively. Sequence analysis indicated that the deduced amino acid sequences was in agreement with the characterization of the amino acid present in the human lg Fab fragment. CONCLUSION: The cloning and sequencing of a human anti-Rhesus (D) antibody Fab fragment cDNA will make benefits for production of recombinant anti-Rhesus (D) antibody and prevention of Rh haemolytic disease in the newborn.
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AIM: To clone and express a human monoclonal anti-D Fab fragment in E. coli and make benefits for the expression of the whole immunoglobulin molecules of anti-D. METHODS: The gene of anti-D Fab fragment was cloned into the phagemid vector pComb3. After analyzing by PCR and restriction site analysis, the recombinant was expressed in E. coli and the expressed protein was analyzed by SDS-PAGE and ELISA. RESULTS: The result of SDS-PAGE confirmed that E.coli expressed a 48 kD protein. The ELISA result demonstrated that the cell culture supernatant reacted with Rh+ group O human erythrocytes, but was not recognized by Rh-group O human erythrocytes. CONCLUSION: Expressed Fab fragment has the antigenic specificity for human erythrocytes.