Chinese Blood Donors Research Articles

The efficacy of HBsAg detection using electro-chemiluminescence immunoassay for blood donor screening in China

Background: The chemiluminescence immunoassay (CLIA) has been a well-established method for HBsAg detection in blood donors worldwide. However, only enzyme-linked immunosorbent assay (ELISA) method was permitted to use for blood donor HBsAg screening in China. In this study, the efficacy of HBsAg detection using electro-CLIA (ECLIA) for blood donor in China was evaluated. Methods: A total of 5,021 samples were tested for HBsAg with one ECLIA (Elescys) and two ELISAs (ELISA 1 and ELISA 2). A pre-defined confirmatory algorithm was used for test result confirmation. The sensitivity and specificity of these assays for HBsAg screening were compared. Results: A total of 23 among the 5,021 screened samples were confirmed positive and 4,998 were confirmed negative. The sensitivities of the Elecsys, ELISA 1 and ELISA 2 were 100% (95% CI, 85.18–100%), 73.91% (95% CI, 51.59–89.77%) and 65.22% (95% CI, 42.73–83.62%) respectively. The coefficient of variation for Elecsys is lower than those of ELISA methods. Two false positives and 6 false negatives results were found in the ELISA 1; 5 false positives and 8 false negative were found in the ELISA 2. Conclusions: The ECLIA is sufficient for HBsAg screening, which can increase the efficacy of HBsAg detection in the Chinese blood donor.

A novel HLA-E allele, HLA-E*01:12:01:01, identified in a healthy Chinese blood donor.

HLA-E*01:12:01:01 differs from HLA-E*01:01:01:01 by a single nucleotide in exon 5 changing 276 proline to glutamine.

Prevalence of HIV infection among Chinese voluntary blood donors during 2010-2017: an updated systematic review and meta-analysis.

Understanding the latest human immunodeficiency virus (HIV) epidemic in voluntary blood donors could be of great value to further increase blood safety in China, as transfusion-transmitted infection places a heavy burden on both infected individuals and the whole society. Therefore, we evaluated the national HIV prevalence of voluntary blood donors in China and characteristics of HIV-infected blood donors. We searched literature in Chinese and English concerning the prevalence of HIV infections in Chinese voluntary blood donors from 2010 to 2017, yielding 97 eligible papers. We performed a meta-analysis to calculate pooled HIV prevalence, and characteristics of HIV-infected blood donors were also extracted. The pooled sample consisted of 21,100,755 voluntary blood donors and 4,755 HIV-infected blood donors. Pooled HIV prevalence of China voluntary blood donors during 2010 to 2017 was 21.02 in 100,000. Pooled HIV prevalence varied in different provinces, showing greater severity in Southwest, Northwest, and South China. Subgroup analysis also showed a significantly increasing trend from 2010 to 2017. The majority of HIV-infected blood donors in China were male, young, unmarried, nonlocal residents, receiving 12 years or less of schooling, and first-time donors. Nearly 90% of HIV-infected blood donors acquired their infections through sexual contact. The prevalence of HIV increased in China among voluntary blood donors during 2010 to 2017, highlighting the risk of HIV transmission by transfusion. Blood centers and public health services should improve screening and intervention programs targeting voluntary blood donors and expand education on blood safety in areas experiencing severe epidemics and among high-risk populations.

In a healthy Chinese blood donor, a novel allele, HLA‐E*01:03:07 was detected

The novel HLA-E*01:03:07 allele, differs from E*01:03:01 by a single synonymous change in exon 3.

Hepatitis C virus prevalence and incidence estimates among Chinese blood donors.

Hepatitis C virus (HCV) is an important transfusion-transmitted virus with global significance. The objective of this study was to evaluate the HCV prevalence and incidence among Chinese blood donors from 2013 to 2016. Whole blood and apheresis platelet donations collected from five Chinese blood centers from June 1, 2013, to December 31, 2016, were screened in parallel by two different enzyme-linked immunosorbent assays for anti-HIV 1/2, hepatitis B surface antigen, anti-HCV, and syphilis. Screening-reactive samples were further confirmed by western blot. Confirmatory positive rates among first-time and repeat donors were used to estimate the prevalence and incidence rates. Multivariable logistic regression modeling was used to examine factors associated with HCV infection. A total of 1,276,544 donations were collected from five Chinese blood centers, of which an estimated 1203 were confirmed HCV positive. The overall HCV prevalence among first-time donors was 166.56 per 100,000 donors (95% confidence interval, 156.04-177.08). The HCV incidence rate was estimated to be 15.21 (95% confidence interval, 11.83-19.56) per 100,000 person-years among repeat donors. Multivariable logistic regression results showed that increased age, lower educational levels, ethnicity, and occupation were all important factors associated with HCV confirmatory status among first-time donors (p < 0.01). HCV infection is still an important concern for transfusion safety in China. Our findings indicate that continued strong efforts are needed to monitor and control the risk of transfusion-transmitted HCV infection in China. Moreover, to reduce unnecessary donor loss, HCV donor screening procedures should be improved by incorporating confirmatory testing into routine blood center operations.

Prevalence of hepatitis G virus infection among 67,348 blood donors in mainland China

BackgroundHepatitis G virus (HGV) infection transmitted from blood donors is a concern in China, as many articles about HGV infection in Chinese blood donors from different provinces have been published. This study aimed to evaluate the overall prevalence of HGV infection in Chinese blood donors and analyse the potential risk of HGV infection through blood transfusion in China.MethodsWe performed a literature search in PubMed, EMBASE, Web of Science, the Chinese BioMedical Literature Database (CBM) and the China National Knowledge Infrastructure (CNKI) up to October 2018 regarding the prevalence of HGV in Chinese blood donors. Eligibility assessment and data extraction were conducted independently by 2 researchers, and meta-analysis was performed to synthesize the data. Heterogeneity was evaluated using Cochran’s Q test and quantified using the I2 statistic. Subgroup analyses were performed to identify the possible sources of heterogeneity. Publication bias was assessed using both funnel plot and Egger’s tests.ResultsA total of 102 studies with 67,348 blood donors published from 1996 to 2016 and covering 26 provinces or municipalities were included for further analyses. The pooled prevalence of HGV was 3.91% (95%CI: 3.18–4.71%) by enzyme immune assay/enzyme linked immunosorbent assay (EIA/ELISA) and 3.25% (95%CI: 2.35–4.26%) by polymerase chain reaction (PCR). The prevalence of HGV may be significantly affected by region, province or municipality and potentially by the paid/voluntary status of the blood donors. No significant difference was found between plasma and full blood donation.ConclusionsThe prevalence of HGV in blood donors from China was similar to that in blood donors from many other countries and higher than that of some other hepatitis viruses, such as hepatitis B virus. The risk of transfusion-transmitted HGV still exists after routine blood donor screening, especially in those patients coinfected with other hepatitis viruses and/or HIV. On the basis of our study, we may suggest adding HGV screening for blood transfusions in mainland China in the future.

Analysis of hepatitis B virus (HBV) drug resistance variations in HBV carriers of Chinese blood donors

Background: To analyze hepatitis B virus (HBV) mutations of nucleoside drug resistance in blood donors of Shantou Central Blood Station. Methods: A total of 22,539 blood donors in Shantou City in 2014 were recruited in the study. Two hundred and one blood samples were detected positive by two types of enzyme-linked immunosorbent assay (ELISA) and 99 cases of HBV positive samples were detected by fluorescence quantitative polymerase chain reaction (PCR). Among them, 45 cases with viral loads greater than 1,000 IU/mL were sequenced by PCR sequencing method. Drug resistance mutation sites of sample DNA sequences were analyzed. Results: All known 10 drug resistant sites of HBV were not detected from these 45 cases of HBV blood donor carriers. Conclusions: The prevalence of HBV strains from blood donors in Shantou were wild-type.

Identification of the novel HLA-C*04:286 allele by next-generation sequencing in a Chinese cord blood donor.

HLA-C*04:286 has a single nucleotide substitution at position 44 G>A when compared to C*04:03:01.

Identification of hepatitis E virus subtype 4f in blood donors in Shanghai, China

Hepatitis E virus (HEV) has been divided into eight genotypes and approximately thirty subtypes. Past studies of blood donors have revealed a substantial prevalence of HEV infection. We examined anti-HEV antibodies and HEV RNA in Chinese voluntary blood donors (VBDs). Blood specimens were collected during 2010–2011, 2014–2015, and 2018, and tested for anti-HEV IgG and IgM antibodies. HEV RNA was tested using real-time PCR and nested reverse transcription PCR (RT-PCR). Phylogenetic analysis determined the genotype using MEGA 7.0. Among 4044 VBDs, 2774 were men (68.6%). In total, 19.8% and 1.1% of the VBDs were reactive to anti-HEV IgG and IgM, respectively. The seroprevalence of anti-HEV IgG was significantly associated with age and time period (P < 0.05), whereas anti-HEV IgM was associated with anti-Treponema pallidum and time period (P < 0.05). A total of five specimens were positive for HEV RNA with normal ALT levels. Subtype 4f (n=1; in the specimens reactive to anti-HEV IgM) and 4d (n=3; 1 in the specimens reactive to anti-HEV IgM and 2 in the anti-HEV negative specimens) were found. The last specimen positive for HEV RNA was not genotyped due to failure in amplifying the partial sequence. In conclusion, our study identified HEV subtype 4f for the first time in China. Additionally, we confirmed the high prevalence of HEV in Chinese VBDs. These findings suggest a substantial risk of transfusion-transmitted HEV. Therefore, screening for HEV among Chinese VBDs might be warranted to prevent further transfusion-mediated spread of HEV.

Estimation of hepatitis B-positive rates in Chinese blood donors by combining predonation and postdonation screening results.

Chinese blood centers use Hepatitis B surface antigen (HBsAg) rapid test (RT) in pre-donation and two rounds of screening with different enzyme-linked immunosorbent assays in post-donation. Nucleic acid testing (NAT) on screening non-reactive (SC-) donations has been gradually implemented since 2010. Yet RT+ and SC-/NAT+ donors are seldom included in hepatitis B virus (HBV) positive rate estimates in Chinese blood donors. We performed HBsAg neutralization test (NT) on whole blood (WB) with pre-donation RT+ results and post-donation screening reactive (SC+) samples from Mianyang and Chongqing in 2015. The annual totals of pre- and post-donation NT+ donors were combined with the annual totals of SC-/NAT+ donors to derive the estimated HBV positive rates. In Mianyang and Chongqing, 59.4% and 68.2% of RT+ donors in Jan-Aug 2015 contributed for NT, 95.5% and 97.2% of which were NT+ respectively. In 2015, 422 and 667 donors from Mianyang and Chongqing respectively were HBsAg RT+, yielding estimated 403 and 648 pre-donation RT+/NT+ deferrals. 411 and 668 post-donation SC+ samples were NT tested from Mianyang and Chongqing, of which 249 and 323 were NT+ respectively. An estimated 63 donors in Mianyang and 88 donors in Chongqing were SC-/NAT+. The estimated HBV confirmed positive rate in blood donors are 1.59% in Mianyang and 1.01% in Chongqing. Pre-donation HBsAg RT effectively intercepts donations from HBV infected donors. Using NT confirmatory results from RT+, SC+ and SC-/NAT+ donors, this study provides a model for more accurate estimation for HBV positive rates in China.

Identification of the novel HLA-A*31:124 allele by sequence-based typing in a Chinese cord blood donor.

HLA-A*31:124 differs from HLA-A*31:01:02:01 by a single-nucleotide substitution at position 491 C>G.

Individual differences of plasma proteins and factors in fresh frozen plasma from Chinese regional blood donors.

Currently, single fresh frozen plasma (FFP) for clinical use is derived from individual blood donors. The objective of this study is to investigate the differences in single FFP units to make related strategies for improving FFP transfusion efficacy. 120 units of single FFP were selected randomly from Chinese PLA Clinical Blood Transfusion Center in Beijing, China. Single FFP samples were thawed in 37°C water bath and were assessed immediately for total protein (TP), albumin (Alb), fibrinogen (Fg), factor V (FV), factor VIII (FVIII), antithrombin-III (AT-III) and protein C (PC). Multiple comparisons were employed to analysis the differences. The quality levels of 120 single FFP units showed wider ranges and presented normal distribution. Fg, FV and PC showed larger fluctuation range but TP, Alb, FVIII and AT-III showed smaller. The mean level of TP was 56.07g/L and FVIII was 0.62IU/mL. There were no significant differences to genders in single FFP units. FFP from younger people with 18-30years old showed a trend towards reduced activity of coagulation factors, especially FV and FVIII. TP and Alb levels in FFP with type O were significantly higher than that in non-O type, but FVIII, AT-III and PC levels were lower in type O than that in non-O type. In a word, the whole quality of single FFP units from Chinese regional donors was acceptable, except FVIII. There were great differences of plasma proteins and factors in single FFP units, age and ABO blood type were main influence factors.

Occult HBV infection in Chinese blood donors: role of N-glycosylation mutations and amino acid substitutions in S protein transmembrane domains

ABSTRACT Occult hepatitis B virus infection (OBI) is a low-level asymptomatic phase of HBV infection. Evidence of OBI clinical relevance is emerging but the mechanisms of its occurrence remain unclear. In this study, the molecular characteristics of 97 confirmed OBI from Chinese blood donors were analyzed and relevant mutations were identified. Recombinant HBsAg bearing these mutations were expressed in vitro and the antigenicity and HBsAg secretion properties were analyzed. Results showed that 45 (46.4%) genotype B, 50 (51.5%) genotype C, and 2 (2.1%) genotype D sequences were identified. Two groups of mutations in the S gene were significantly associated with OBI. The first group included mutations creating new N-linked glycosylation sites at positions s116, s123, s130, and s131 + s133 or removing the existing one at s146. Mutations TCT123-125NCT/NFT were associated with reduced antigenicity, while TST116-118NST, GTS130-132NTS, and TSM131-133NSS/NYT/NST were associated with varying levels of impaired HBsAg secretion. N146 mutations had no effect on HBsAg production pattern. The second group included substitutions within the S transmembrane domains TMD1-3. Only mutations C85R, L87R, L88R, and C90R within TMD2 were associated with defective HBsAg production. These mutations appear to be rare and mostly strain specific but they may contribute to the multifactorial occurrence of OBI.

Polymorphisms of MICA gene and their linkage disequilibrium with HLA-B among ethnic Han Chinese from Shenzhen

To study the distribution of MICA alleles among ethnic Han Chinese blood donors from Shenzhen and their linkage disequilibrium with HLA-B gene. For 143 randomly selected blood donors, the MICA and HLA-B alleles were determined with a PCR-sequence based typing (SBT) method. Allelic frequency, haplotypic diversity and linkage disequilibrium were analyzed with a Pypop software. Thirteen MICA and 35 HLA-B alleles were identified among the 143 blood donors, among which MICA*008:01 had the highest frequency (76/286), whilst MICA*008:01-HLA-B*40:01 and MICA*010-HLA-B*46:01 were the most common haplotypes. No novel allele was identified. The allele frequencies, haplotype diversities and linkage disequilibrium parameters under a high resolution can facilitate further studies and applications of the MICA and HLA-B genes.

A variant RhAG protein encoded by the RHAG*572A allele causes serological weak D expression while maintaining normal RhCE phenotypes.

The molecular events resulting in a weak D phenotype include missense mutations, in-frame insertion, or deletion mutations of the RHD gene and hybrid RHD-CE-D hybrid alleles. Mutations in genes encoding the proteins that are required for proper membrane expression of Rh proteins, such as RhAG and ankyrin 1, can lead to absent or weakened expression of Rh antigens. Blood sample from a Chinese blood donor with a serological weak D phenotype was collected. RhAG antigen expression, RhD, and RhCE phenotypes were determined. Analysis of the RHD and RHCE genotypes by RH multiplex ligation-dependent probe amplification (MLPA), Sanger sequencing of the RHD exons, and next-generation sequencing (NGS) of the RHAG and ANK1 exons were performed. Expression studies in vitro were conducted by lentivirally transducing the mutant RHAG*572A or wild-type RHAG, in combination with either RHD or RHCE constructs, into HEK 293 T cells. The expression of RhAG, RhD, and RhCE antigens was analyzed by flow cytometry. Serological weak D and normal C + c- E- e + phenotypes, normal CCDDee genotype determined by RH-MLPA, and normal sequence of the RHD gene by Sanger sequencing were demonstrated. A homozygous variant (c.572G > A, p.Arg191Gln) of the RHAG gene was revealed by NGS analysis. Normal RhAG, weak RhD, and normal RhCE antigens were detected in cells transduced with the mutant RHAG*572A, the mutant RHAG*572A and RHD, and the mutant RHAG*572A and RHCE constructs, respectively. The homozygous presence of RHAG*572A allele results in weak D expression. It does not affect RhCE expression.

Molecular biology study of RHD gene in Chinese Han voluntary blood donors with RhD-negative blood type

Objective To explore the RHD gene structure of Chinese Han voluntary blood donors with RhD-negative blood type, and to conduct a molecular biological analysis of a newly discovered RHD gene mutation. Methods From 2016 to 2017, a total of 85 Chinese Han voluntary blood donors who participated in blood donation in Shandong Blood Center were selected as the subject by randomized digital table. Real-time fluorescence quantitative (RQ)-PCR method was used to detect exon 7 of RHD gene in DNA samples from 85 blood donors. The multiplex PCR-sequence specific primer (SSP) method was used to detect exons 3 to 7 and 9 of RHD gene in DNA samples from these 85 blood donors. The RHD gene in DNA samples from 30 blood donors whose DNA samples expressed RHD gene exon 7 were sequenced using a fluorescently labeled Sanger dideoxy chain termination method. The procedure of this study is in accordance with the requirements of the revised World Medical Association Declaration of Helsinki in 2013. Informed consent was obtained from each blood donor. Results ① In 85 blood donors with RhD-negative blood type, DNA samples of 30 donors had exon 7 of RHD gene, and of 55 blood donors had deletion of exon 7 of RHD gene.② Among the 30 donors with RHD gene exon 7, the DNA samples of 29 donors had exons 3 to 7 and 9 of the RHD gene. Exon 3, 4, 5, 7 and 9 of RHD gene were present in DNA sample of one donor, but exon 6 was deleted. DNA samples from 55 donors without RHD gene exon 7, were deletion of RHD gene exons 3 to 7 and 9. ③ Among the 30 blood donors with RHD gene exon 7, 29 DNA samples had one c. 1227G>A point mutation on RHD gene exon 9. There was a non-sense mutation in c. 933C>A on RHD gene exon 6 in one blood donor′s DNA sample with deletion of the exon 6 of RHD gene. This mutation produced a stop codon, resulting in inconsistent multiplex PCR-SSP and DNA sequencing results of RHD gene in this blood donor. Conclusions The deletion of RHD gene is the main molecular mechanism that causes the RhD-negative phenotype of Chinese Han people. The RHD gene c. 1227G>A mutation is a major feature of Del phenotype. A new c. 933C>A mutation in the RHD gene results in a RhD-negative phenotype. Key words: Rh-Hr blood system; RhD-negativity; Red cells; Immunohematology; Immunogenetics

Incidence of hepatitis B virus infection in young Chinese blood donors born after mandatory implementation of neonatal hepatitis B vaccination nationwide.

This study was carried out to determine the incidence of hepatitis B virus (HBV) infection in the young generation born after mandatory implementation of hepatitis B vaccination since 1992. Repeat blood donors born between 1992 and 1997 were enrolled, who gave blood at least twice during the past 3years. Donors were tested for HBV infection markers of HBsAg, anti-HBc, anti-HBs and viral DNA by immunoassays (EIAs) and nucleic acid tests (NAT). A total of 14937 pre-donation screening qualified young repeat donors aged 18-23years were tested with 9 (0.06%) being HBsAg by EIA and 10 (1:1494) HBV DNA positive by Ultrio NAT (10.4 IU/mL), respectively. HBV DNA was further detected in 1:192 (9/1732) anti-HBc+ repeat donors with Ultrio Plus NAT (3.4 IU/mL). Most cases were identified as occult HBV infection (OBI). Of 14937 repeat donors, 20.9% were anti-HBc+ positive, while approximately 50% of 12024 repeat donors were anti-HBs negative or had levels <100 IU/L. HBsAg+ or OBI strains were classified as wild type of genotype B or genotype C. Incident HBV infection in repeat donors was approximately 1:18.5 person-years (1.1%/year) but significantly less frequent in donors with confirmed HBV vaccination (2.4%-3.3%) than those unsure of vaccination status (10.5%; P=.0023). Hepatitis B virus vaccination appears largely protective of HBV infection, but incidence of infections increases in young adults with mostly undetectable or low anti-HBs or occasionally high anti-HBs. A boost of hepatitis B vaccine for adolescents prior to age 18years may reduce HBV infection, and implementation of more sensitive NAT in blood donation screening may improve HBV safety in blood transfusion.

Update on epidemiology of hepatitis B virus among blood donors in China

China is one of the countries with high prevalence of hepatitis B virus (HBV) infection. It is estimated that approximately 100 million people in China are infected with HBV. We aimed to review the prevalence of HBV in Chinese blood donors. With the search term of ‘(hepatitis b virus) and (prevalence or epidemiology) and (blood donors) and (Chinese)’, we searched PubMed (https://www.ncbi.nlm.nih.gov/pubmed) and CNKI (http://www.cnki.net/) for literature in English and Chinese, respectively. The prevalence of hepatitis B surface antigen (HBsAg) in Chinese general population has declined from 9·75% in 1992 to 7·18% in 2006, as a consequence of implementation of nationwide universal neonatal HBV vaccination. The prevalence of HBsAg in blood donors is about 0·49–1·56% by enzyme immunoassays (EIAs) after predonation screening with HBsAg rapid strip test and health consultation, which is significantly lower than that in the general population. HBV DNA is detected by nucleic acid tests (NATs) at a rate of 0·01–0·11% among HBsAg‐negative blood donors, which is identified mostly as occult HBV infection (OBI). The prevalence of HBV in Chinese blood donors is about 1%. In contrast to countries with low HBV prevalence, anti‐HBc testing cannot be applied to routine screening of HBV infection because the high anti‐HBc prevalence in Chinese blood donors would lead to unacceptably high donor deferral. Therefore, to further reduce transfusion transmission of HBV, it is of great necessity to apply highly sensitive NAT to test HBV DNA in Chinese blood donors.

A pilot serosurvey of Babesia microti in Chinese blood donors.

Babesia spp. are tick-borne, intraerythrocytic protozoan parasites, several of which are transfusion-transmissible. Transfusion-transmitted babesiosis poses serious risk to a diverse patient population, including neonates, patients aged >50 years, the asplenic and the immunocompromised that are over-represented among transfusion recipients. Despite reports of B. microti and B. venatorum in People's Republic of China (PRC), no surveillance of blood donors for Babesia has previously been undertaken. We sought to determine the rates of B. microti seroreactivity in a sample of blood donors in the PRC. A pilot serosurvey was conducted of community blood donors (n = 1000) who donated July-August 2016 at Mudanjiang Blood Center (Heilongjiang Province) using indirect fluorescent antibody testing for antibodies against B. microti. The slides were prepared using B. microti-infected hamster blood. Samples that were initially positive to a titre of 64 were subjected to repeat IFA testing. Final seroreactivity was based on repeat reactivity to ≥64. A total of 1000 individual donor samples were evaluated, comprising 888 whole blood and 112 platelet donations. Thirteen of 1000 (1·3%) donors were seroreactive for B. microti [8 (0·8%) and five (0·05%) at titres of 64 and 128, respectively]. Our preliminary findings support the need for expanded Babesia surveillance in Chinese blood donors, replete with molecular evaluation, to evaluate the risk to the blood supply.

Seroprevalence of Toxoplasma gondii infection in blood donors in mainland China: a systematic review and meta-analysis.

Toxoplasma gondii transmitted from blood donors to receiving patients has become a concern as numerous articles about the epidemiology of T. gondii infection in blood donors from different provinces have been published in China. This study aimed to evaluate the seroprevalence of T. gondii infection in Chinese blood donors using a meta-analysis. A total of 40 eligible studies, published from 1986 to 2017 and covering 18 provinces and municipalities were included. Among a total of 49,784 Chinese blood donors, the overall IgG seroprevalence of T. gondii infection was 6.26% (95% CI: 4.62%–8.13%). The highest prevalence was in the Northeast of China and the lowest in Central China. The infection rate increased slowly over the years, but not significantly. A statistically significant correlation was found between the seroprevalence of T. gondii infection and the detection method and educational level (p < 0.01). There was no relationship between age, gender, occupation and blood type and seroprevalence of T. gondii (p > 0.05). The prevalence of antibodies to T. gondii in Chinese blood donors was lower than in other countries, but the risk of transfusion-transmitted toxoplasmosis still exits. More concise methods are still needed to evaluate the possibility of transfusion-transmitted toxoplasmosis from blood donors.