Patients with Asian-type DEL can safely be transfused with RhD-positive blood.

Red blood cells (RBCs) of Asian-type DEL phenotype express few RhD proteins and are typed as serologic RhD-negative (D-) phenotype in routine testing. RhD-positive (D+) RBC transfusion for patients with Asian-type DEL has been proposed but has not been generally adopted because of a lack of direct evidence regarding its safety and the underlying mechanism. We performed a single-arm multicenter clinical trial to document the outcome of D+ RBC transfusion in patients with Asian-type DEL; none of the recipients (0/42; 95% confidence interval, 0-8.40) developed alloanti-D after a median follow-up of 226 days. We conducted a large retrospective study to detect alloanti-D immunization in 4045 serologic D- pregnant women throughout China; alloanti-D was found only in individuals with true D- (2.63%, 79/3009), but not in those with Asian-type DEL (0/1032). We further retrospectively examined 127 serologic D- pregnant women who had developed alloanti-D and found none with Asian-type DEL (0/127). Finally, we analyzed RHD transcripts from Asian-type DEL erythroblasts and examined antigen epitopes expressed by various RHD transcripts in vitro, finding a low abundance of full-length RHD transcripts (0.18% of the total) expressing RhD antigens carrying the entire repertoire of epitopes, which could explain the immune tolerance against D+ RBCs. Our results provide multiple lines of evidence that individuals with Asian-type DEL cannot produce alloanti-D when exposed to D+ RBCs after transfusion or pregnancy. Therefore, we recommend considering D+ RBC transfusion and discontinuing anti-D prophylaxis in patients with Asian-type DEL, including pregnant women. This clinical trial is registered at www.clinicaltrials.gov as #NCT03727230.

Occult Hepatitis B Virus Infection and Liver Fibrosis in Chinese Patients.

BACKGROUND: The impact of hepatitis B surface antigen (HBsAg)-negative/hepatitis B virus (HBV) DNA-positive occult HBV infection (OBI) on the severity of liver fibrosis remains unclear. METHODS: A total of 1772 patients negative for HBsAg but positive for antibody to hepatitis B core antigen (HBcAg), stratified by the presence or absence of OBI, were selected for long-term carriage leading to elevation of ≥2 of 4 liver fibrosis indexes-hyaluronic acid (HA), laminin, type III procollagen peptide (PCIII), and type IV collagen (CIV)-at testing in a Chinese hospital. Patients were tested for serum viral load, HBV markers, and histopathological changes in liver biopsy specimens. RESULTS: OBI was identified in 148 patients with liver fibrosis (8.4%), who had significantly higher levels of HA, laminin, PCIII, and CIV than 1624 fibrotic patients without OBI (P < .05). In 36 patients with OBI who underwent liver biopsy, significant correlations were observed between OBI viral load and serum HA levels (P = .01), PCIII levels (P = .01), and pathological histological activity index (HAI) scores (P < .001), respectively; HAI scores and PCIII levels (P = .04); HBcAg immunohistochemical scores and HA levels (P < .001); and HBcAg immunohistochemical scores and PCIII levels (P = .03). Positive fluorescent in situ hybridization results were significantly more frequent in patients with OBIs (80.6% vs 37.5% in those without OBIs). Among patients with OBIs, HBcAg was detected in the liver tissue in 52.8% and HBsAg in 5.6%. CONCLUSIONS: OBI status appears to be associated with liver fibrosis severity.

Successful prenatal therapy for anti-CD36-mediated severe FNAIT by deglycosylated antibodies in a novel murine model.

Recent studies have shown that maternal anti-CD36 antibodies represent a frequent cause of fetal/neonatal alloimmune thrombocytopenia (FNAIT) in Asian and African populations. However, little is known about the pathomechanism and antenatal treatment of anti-CD36-mediated FNAIT. Here, we established a novel animal model to examine the clinical features of pups from immunized Cd36-/- female mice after breeding with wild-type male mice. Mild thrombocytopenia was observed, but high pup mortality was also documented (40.26%). Administration of intravenous immunoglobulin (IVIG) (1 g/kg) on days 7, 12, and 17 to immunized Cd36-/- mothers after breeding reduced fetal death (12.70%). However, delaying the IVIG administration series on days 10, 15, and 20 did not reduce fetal death (40.00%). In contrast, injection of deglycosylated anti-CD36 (deg-anti-CD36) polyclonal antibodies (5 mg/kg) on days 10, 15, and 20 significantly reduced fetal death (5.26%). Subsequently, monoclonal antibodies (mAbs) against mouse CD36 were developed, and one clone producing high-affinity anti-CD36 (termed 32-106) effectively inhibited maternal antibody binding and was therefore selected. Using the same approach of deg-anti-CD36, the administration of deg-32-106 significantly reduced fetal death (2.17%). Furthermore, immunized Cd36-/- mothers exhibited placental deficiency. Accordingly, maternal anti-CD36 antibodies inhibited angiogenesis of placenta endothelial cells, which could be restored by deg-32-106. In summary, maternal anti-CD36 antibodies caused a high frequency of fetal death in our animal model, associated with placental dysfunction. This deleterious effect could be diminished by the antenatal administration of IVIG and deg-mAb 32-106. Interestingly, treatment with deg-32-106 seems more beneficial considering the lower dose, later start of treatment, and therapy success.

Incidence of anti-D alloimmunization in D-negative individuals receiving D-positive red blood cell transfusion: A systematic review and meta-analysis.

BACKGROUND AND OBJECTIVES: The transfusion of D-negative red blood cells (RBCs) to D-negative patients has been widely adopted to prevent anti-D alloimmunization, especially in women of childbearing age. Still, transfusion of D-positive RBCs to D-negative recipients is occasionally inevitable in practice, and the resulting incidence of anti-D in different D-negative groups of patients has not been well summarized. MATERIALS AND METHODS: We searched the relevant literature using PubMed, Cochrane Library, and Embase databases from inception date to 30 September 2021. We looked for studies of anti-D occurring in D-negative recipients who received D-positive RBC transfusions. The anti-D incidence was summarized with 95% confidence intervals (CIs). Data with similar characteristics were combined using a random-effects model. RESULTS: About 42 studies (2226 cases), which found anti-D, the exact volume of D-positive RBC transfused, and the follow-up time for anti-D detection, met the inclusion criteria. The pooled anti-D incidence was 64% (95% CI, range 55%-74%) in volunteers receiving small volumes of D-positive RBCs, 84% (95% CI, 74%-94%) in those receiving whole units, 26% (95% CI, 19%-32%) in mixed patients, 12% (95% CI, 8%-16%) in oncology patients, 27% (95% CI, 13%-40%) in trauma patients, 4% (95% CI, 0%-8%) in immune-compromised transplant patients, and 6% (95% CI, 1%-39%) in those with AIDS. CONCLUSION: Compared with the high frequency of anti-D in healthy D-negative volunteers given D-positive RBCs, we found a lower rate of anti-D immunization in various D-negative patients and almost none in transplant and AIDS patients.

Complete genome sequencing and evolutionary analysis of hepatitis C virus subtype 6a, including strains from Guangdong Province, China.

We performed an evolutionary analysis using whole genome sequence isolates of hepatitis C virus (HCV) 6a from Guangdong Province and reference sequences from various countries. Less than 5% of the HCV genome was found to be under positive selection. The E1 and E2 proteins had the highest proportion of positively selected sites both within and outside of CD8 T cell epitopes in all of the strains. Regions corresponding to CD8 T cell epitopes were under negative selection except in the isolates from Guangdong. Furthermore, we found evidence of three introductions of the virus into Guangdong from Vietnam and other Southeast Asian countries. Thus, this study provides information about the transmission of HCV 6a by comparison of full-length sequences, indicating the impact of selective constraints in Guangdong and across China.

Preliminary mechanism in fetal alloimmune thrombocytopenia associated with anti-HPA 15b antibodies.

OBJECTIVE: Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is a bleeding disease that can cause fetal hydrops, a rare but life-threatening condition in which abnormal amounts of fluid accumulate in one or two areas of the fetus's body. A case of FNAIT with fetal hydrops caused by anti-HPA-15b antibodies was involved in this study, as we investigated whether or not anti-HPA-15b antibodies can induce endothelial angiogenesis and apoptosis. METHODS: The monoclonal antibody immobilization of platelet antigens assay (MAIPA) was used to identify anti-HPA-15b antibodies. The three groups in Tube formation and apoptosis assays were the PBS group, the AB serum IgG group, and the anti-HPA-15b serum IgG group, all reacted with HPA-15bb HUVEC. RESULTS: The presence of anti-HPA-15b antibodies was found in this case by MAIPA assay. The OD values are 0.33 and 0.21, reacted with HPA-15bb and HPA-15ab platelets, respectively (cutoff OD value = 0.2). Quantitative analysis revealed that the length of capillary-like tube induced by anti-HPA-15b antibodies was significantly decreased over that of AB serum IgG (*p = 0.0005), but weaker than when incubated with thrombin (**p = 0.0009). The apoptosis results show a significantly increased number of apoptotic endothelial cells in the anti-HPA-15b antibody IgG group when compared with the PBS and AB serum IgG groups (*p < 0.0001, **p < 0.0001). In addition, there is no statistical difference between the PBS and AB serum groups. CONCLUSION: Anti-HPA-15b antibodies can inhibit angiogenesis and induce apoptosis. This may associate with hydrops fetalis (HF), or fetal hydrops of FNAIT.

Brucella Outer Membrane Lipoproteins 19 and 16 Differentially Induce Interleukin-18 Response or Pyroptosis in Human Monocytic Cells.

BACKGROUND: Brucella species are Gram-negative intracellular bacteria that causes severe inflammatory diseases in animals and humans. Two major lipoproteins (L19 and L16) of Brucella outer membrane proteins were studied to explore the association with inflammatory response of human monocytes (THP-1). METHODS: Activated THP-1 cells induced with recombinant L19 and L16 were analyzed in comparison with unlipidated forms (U19 and U16) and lipopolysaccharide (LPS) of Brucella melitensis, respectively. RESULTS: Secretion of inflammatory factors tumor necrosis factor-α, interleukin (IL)-6, and IL-1ß was significantly increased from L19, L16, or both stimulated THP-1 cells. High secretion of IL-18 was detected only from L19-induced cells. Signaling of those cytokine responses was identified mainly through the P38-mitogen-activated protein kinase pathway, and signaling of L19-induced IL-1ß response partly occurred via necrosis factor-κB. While exploring different forms of IL-18, we found that L19-induced production of active IL-18 (18 kD) occurred through upregulating NLRP3 and activating caspase-1, whereas L16-induced production of inactive IL-18 fragments (15 kD and 16 kD) occurred through activating caspase-8/3. We also found that L19 upregulated phosphorylation of XIAP for inhibiting caspase-3 activity to cleave IL-18, whereas L16 activated caspase-3 for producing GSDME-N and leading to pyroptosis of THP-1 cells. CONCLUSIONS: Brucella L19 and L16 differentially induce IL-18 response or pyroptosis in THP-1 cells, respectively.

Role of core protein mutations in the development of occult HBV infection.

BACKGROUND & AIMS: Occult HBV infection (OBI) is associated with transfusion-transmitted HBV infection and hepatocellular carcinoma. Studies on OBI genesis have concentrated on mutations in the S region and the regulatory elements. Herein, we aimed to determine the role of mutations in the core region on OBIs. METHODS: An OBI strain (SZA) carrying 9 amino acid (aa) substitutions in the core protein/capsid (Cp) was selected by sequence alignment and Western blot analysis from 26 genotype B OBI samples to extensively explore the impact of Cp mutations on viral antigen production in vitro and in vivo. RESULTS: A large panel of 30 Cp replicons were generated by a replication-competent pHBV1.3 carrying SZA or wild-type (WT) Cp in a 1.3-fold over-length of HBV genome, in which the various Cp mutants were individually introduced by repairing site mutations of SZA-Cp or creating site mutations of WT-Cp by site-directed mutagenesis. The expression of HBcAg, HBeAg, and HBsAg and viral RNA was quantified from individual SZA and WT Cp mutant replicons in transfected Huh7 cells or infected mice, respectively. An analysis of the effect of Cp mutants on intracellular or extracellular viral protein production indicated that the W62R mutation in Cp had a critical impact on the reduction of HBcAg and HBeAg production during HBV replication, whereas P50H and/or S74G mutations played a limited role in influencing viral protein production invivo. CONCLUSIONS: W62R and its combination mutations in HBV Cp might massively affect HBcAg and HBeAg production during viral replication, which, in turn, might contribute to the occurrence of OBI. LAY SUMMARY: Occult hepatitis B virus infections (OBIs) have been found to be associated with amino acid mutations in the S region of the HBV, but the role of mutations in the core protein (Cp) remains unclear. In this study, an OBI strain (SZA) carrying 9 amino acid substitutions in Cp has been examined comprehensively in vitro and in vivo. The W62R mutation in Cp majorly reduces HBcAg and HBeAg production during HBV replication, potentially contributing to the occurrence of OBI.

Development of full-length cell-culture infectious clone and subgenomic replicon for a genotype 3a isolate of hepatitis C virus.

Hepatitis C virus (HCV) genotype 3 is widely distributed, and genotype 3-infected patients achieve a lower cure rate in direct-acting antiviral (DAA) therapy and are associated with a higher risk of hepatic steatosis than patients with other genotypes. Thus, the study of the virology and pathogenesis of genotype 3 HCV is increasingly relevant. Here, we developed a full-length infectious clone and a subgenomic replicon for the genotype 3a isolate, CH3a. From an infected serum, we constructed a full-length CH3a clone, however, it was nonviable in Huh7.5.1 cells. Next, we systematically adapted several intergenotypic recombinants containing Core-NS2 and 5'UTR-NS5A from CH3a, and other sequences from a replication-competent genotype 2 a clone JFH1. Adaptive mutations were identified, of which several combinations facilitated the replication of CH3a-JFH1 recombinants; however, they failed to adapt to the full-length CH3a and the recombinants containing CH3a NS5B. Thus, we attempted to separately adapt CH3a NS5B-3'UTR by constructing an intragenotypic recombinant using 5'UTR-NS5A from an infectious genotype 3a clone, DBN3acc, from which L3004P/M in NS5B and a deletion of 11 nucleotides (Δ11nt) downstream of the polyU/UC tract of the 3'UTR were identified and demonstrated to efficiently improve virus production. Finally, we combined functional 5'UTR-NS5A and NS5B-3'UTR sequences that carried the selected mutations to generate full-length CH3a with 26 or 27 substitutions (CH3acc), and both revealed efficient replication and virus spread in transfected and infected cells, releasing HCV of 104.2 f.f.u. ml-1. CH3acc was inhibited by DAAs targeting NS3/4A, NS5A and NS5B in a dose-dependent manner. The selected mutations permitted the development of subgenomic replicon CH3a-SGRep, by which L3004P, L3004M and Δ11nt were proven, together with a single-cycle virus production assay, to facilitate virus assembly, release, and RNA replication. CH3acc clones and CH3a-SGRep replicon provide new tools for the study of HCV genotype 3.

Low prevalence of antibodies against SARS-CoV-2 among voluntary blood donors in Guangzhou, China.

Since the first case of COVID-19 reported in late December of 2019 in Wuhan, China, the SARS-CoV-2 virus has caused approximately 20 million infections and 732 thousand deaths around the world by 11 August 2020. Although the pathogen generally infects the respiratory system, whether it is present in the bloodstream and whether it poses a threat to the blood supply during the period of the outbreak is of serious public concern. In this study, we used enzyme-linked immunosorbent assay (ELISA) to screen total antibodies against SARS-CoV-2 in 2199 blood donors, who had donated blood at the Guangzhou Blood Center during the epidemic. The Ig-reactive samples were further characterized for IgA, IgG, and IgM subtypes by ELISA and viral nucleic acid by real-time polymerase chain reaction. Among the 2199 plasma samples, seven were reactive under total antibodies' screening. Further testing revealed that none of them had detectable viral nucleic acid or IgM antibody, but two samples contained IgA and IgG. The IgG antibody titers of both positive samples were 1:16 and 1:4, respectively. Our results indicated a low prevalence of past SARS-CoV-2 infection in our blood donors, as none of the tests were positive for viral nucleic acid and only 2 out of 2199 (0.09%) of samples were positive for IgG and IgA. There would be a limited necessity for the implementation of such testing in blood screening in a COVID-19 low-risk area.

A nanoenzyme linked immunochromatographic sensor for rapid and quantitative detection of SARS-CoV-2 nucleocapsid protein in human blood.

The establishment of a simple, low-cost, high-sensitive and rapid immunoassay for detecting SARS-CoV-2 antigen in human blood is an effective mean of discovering early SARS-CoV-2 infection and controlling the pandemic of COVID-19. Herein, a smartphone based nanozyme linked immunochromatographic sensor (NLICS) for the detection of SARS-CoV-2 nucleocapsid protein (NP) has been developed on demand. The system is integrated by disposable immunochromatography assay (ICA) and optical sensor devices. Immunoreaction and enzyme-catalyzed substrate color reaction were carried out on the chromatographic strip in a device, of which the light signal was read by a photometer through a biosensor channel, and the data was synchronously transmitted via the Bluetooth to the app in-stored smartphone for reporting the result. With a limit of detection (LOD) of 0.026 ng/mL NP, NLICS had the linear detection range (LDR) between 0.05 and 1.6 ng/mL NP, which was more sensitive than conventional ICA. NLICS took 25 min for reporting results. For detection of NP antigen in clinical serum samples from 21 COVID-19 patients and 80 healthy blood donor controls, NLICS and commercial enzyme linked immunosorbent assay (ELISA) had 76.2% or 47.6% positivity, and 100% specificity, respectively (P = 0.057), while a good correlation coefficient (r = 0.99) for quantification of NP between two assays was obtained. In conclusion, the NLICS was a rapid, simple, cheap, sensitive and specific immunochromatographic sensing assay for early diagnosis of SARS-CoV-2 infection.

Serological screening and genetic analysis of RhCE variants in the Chinese Southern Han donors.

OBJECTIVES: To screen RhCE variants in the Chinese Southern Han donors for molecular genetic analysis. BACKGROUND: More than hundreds of RhCE variant alleles have been described to resulting in weak and/or partial expression of RhCE antigens, generation of low-prevalence antigens and/or absence of a high-prevalence antigen of Rh system, which mainly reported in the people of African origin. In this study, the serological screening and molecular genetic analysis of RhCE variants were performed in the Chinese Southern Han donors. METHODS: The blood samples of E(+) donors were preliminarily collected. Then, RhCE antigens of the E(+) samples were further typed by using two sets of monoclonal anti-C, anti-c, anti-e and another anti-E. When weak expression of RhCE antigens was found, direct sequencing for 10 exons of RHCE gene, RH genotyping analysis by using multiplex ligation-dependent probe amplification, flow cytometric analysis and even cDNA sequencing were performed. RESULTS: A total of 4487 E(+) samples were collected and four samples with weak expression of antigens were detected. RHCE*Ce375G and RHCE*Ce667T variant alleles were identified in two samples with weak expression of e antigen, respectively. But no variant alleles were found in another two samples with weak expression of C antigen. CONCLUSION: The variant RHCE*Ce375G validated by mRNA sequencing and the deduced RHCE*Ce667T alleles were firstly identified in the Chinese population. The DCE haplotype might account for the weak expression of C antigen in two donors.

The apheresis platelet donation was increased after a nationwide ban on family/replacement donation in China.

BACKGROUND: A nationwide ban on family/replacement donation (FRD) went into effect on April 1, 2018 in China. To date, no reports relevant to the trend of plateletpheresis donations before and after a nationwide ban on FRD were found. METHODS: We used two independent full samples, consisting of 135,851 and 82,129 plateletpheresis donors from Guangzhou and Chengdu between October 2012 and September 2019, respectively. A pseudo-panel data approach was applied by grouping three time-invariant covariates - gender, blood donation history, and birth year across 14 cross-sections (a 6-month interval each) to form a total of 24 cohort groups (14 × 24 = 336 cohorts, i.e., cells) with each having common covariates. The outcome was average apheresis platelet units per donor in each cell. We performed a two-piecewise linear mixed model with the cross-section (i.e., time) just right before the ban as a time breakpoint (i.e., 11th cross-section) to examine the trend of outcome with the adjustment of three time-invariant covariates. We removed the FRDs in each of the first 11 cross-sections to detect its possible influence on the trend. RESULTS: The final model for the samples from Guangzhou presented a two-piecewise linear trend of the outcome over time with a horizontal line to the left of the breakpoint (ßtimeBefore11 = 0.0111, p = 0.0976) and a significantly positive linear trend to the right (ßtimeAfter11 = 0.0404, p < 0.0001). The male donors and the donors with plateletpheresis donation history had an increased baseline outcome and a significant outcome change over time after the ban. Such a two-piecewise linear trend pattern can be replicated using the samples from Chengdu with some minor variations. Removing the FRD before the ban can change the pattern. CONCLUSION: The significant increase of the average apheresis platelet units per donor over time after the FRD ban may be related to the implement of the FRD ban and the improved donation behavior of male donors and/or donors with platelet donation history after the ban. Our findings may potentially motivate the policymakers in other countries where the FRD for plateletpheresis donation is still legitimate to phase out their FRD strategy and ultimately achieve 100% voluntary plateletpheresis donation.

Novel hepatitis B virus surface antigen mutations associated with occult genotype B hepatitis B virus infection affect HBsAg detection.

The causative factors of occult hepatitis B infection are complicated and not yet been fully elucidated. Mutations in hepatitis B virus (HBV) S gene are one of the factors may contributing to occult infection. In this study, 89 blood donors with genotype B occult HBV infection were investigated. Fifty-seven hepatitis B surface antigen (HBsAg)-positive/HBV DNA-positive blood donors served as control group for comparison. Occult HBV-related mutations with a high incidence (P < .05) in the S gene were identified. To further verify these occult infection-related mutations, a conservative full-gene expression vector of HBV B genotype (pHBV1.3B) was constructed. Then, the mutant plasmids on the basis of pHBV1.3B were constructed and transfected into HepG2 cells. Extracellular as well as intracellular HBsAg was analysed by electrochemical luminescence and cellular immunohistochemistry. Ten occult infection-related mutations (E2G, Q101R, K122R, M133T, D144E, G145R, V168A, S174N, L175S and I226S) were significantly more frequent in the occult infection group (P < .05). Five of the ten mutations (E2G, D144E, G145R, V168A and S174N) strongly decreased extracellular HBsAg level (P < .05) in the transfection system. Notably, the E2G mutation had the most significant impact on the ratio of extracellular HBsAg (3.8% vs pHBV1.3B) and intracellular HBsAg (239.3% vs pHBV1.3B) (P < .05), and the fluorescence density of E2G mutant HBsAg was significantly higher than that of pHBV1.3B (P < .0001). Hence, ten mutations were associated with genotype B occult HBV infection; E2G and V168A were novel mutations which we confirmed significantly affect HBsAg detection. E2G might cause HBsAg secretion impairment that results in intracellular accumulation and a decrease in HBsAg secretion.

Blood donor recruitment in Guangzhou, China, during the 2019 novel coronavirus (COVID-19) epidemic.

BACKGROUND: The coronavirus disease 2019 (COVID-19) epidemic affected blood collection in Guangzhou, China. STUDY DESIGN AND METHODS: This paper includes three studies. The observational study reported the trends of blood collection during the epidemic in Guangzhou, China. The cross-sectional survey investigated factors influencing blood donation during the COVID-19 epidemic, and a self-administered questionnaire was given to 1584 street whole blood donors (SWBDs) who donated during the epidemic. The randomized controlled trial involved 19 491 SWBDs who donated in 2019 but did not donate during the epidemic. Trial participants were randomly assigned to two intervention groups: Group 1 completed Questionnaire 1, which contained precautionary measures in response to COVID-19 and other messages about blood donation during the epidemic; Group 2 completed Questionnaire 2, which did not include this information. A control group did not receive any questionnaire. RESULTS: As measures were implemented, the number of blood donors increased accordingly. Both first-time and repeat SWBDs perceived the same level of blood need and donated blood because it would save lives. SWBDs who completed Questionnaire 1 expressed a greater intention to donate during the epidemic. Enabling blood donors to perceive a higher level of blood need and a lower level of COVID-19 infection risk related to blood donation mobilized experienced SWBDs to donate within 3 weeks. Intention-to-treat analyses and average-treatment-effect-on-the-treated estimations confirmed that Questionnaire 1 could motivate SWBDs to actually donate blood. CONCLUSION: Various measures could ease blood shortage during the COVID-19 epidemic. Administration of Questionnaire 1 could increase blood donations during the epidemic.

Hydrops fetalis associated with anti-CD36 antibodies in fetal and neonatal alloimmune thrombocytopenia: Possible underlying mechanism.

OBJECTIVES: In the present study, we asked whether anti-CD36 antibodies impair the maturation of erythropoietic stem cells to mature red blood cells (RBCs), leading to anaemia and hydrops fetalis (HF). BACKGROUND: Recent studies have shown the importance of anti-CD36 antibodies in the development of Fetal/Neonatal Alloimmune Thrombocytopenia (FNAIT). In comparison to other types of antibody-mediated FNAIT, anti-CD36 antibodies are frequently associated with anaemia and HF. As mature RBCs do not express CD36, the reason for this phenomenon is currently not fully understood. MATERIAL AND METHODS: A case of FNAIT with signs of HF was characterised in this study. Maternal anti-CD36 antibodies were isolated by an absorption/elution approach. We cultured haematopoietic stem cells (HSCs) with purified anti-CD36 antibodies, and the formation of burst-forming unit-erythroid and colony-forming unit-erythroid (CFU-E/BFU-E) cells was analysed. Apoptosis of HSCs was also investigated. RESULTS: Analysis of the mother showed type-1 CD36 deficiency. Anti-CD36 antibodies were found in maternal serum, as well as on fetal platelets, by ELISA, and the specificity of these antibodies was further substantiated by flow cytometry. In comparison to control IgG, incubation of HSCs with purified anti-CD36 antibodies led to a significant reduction in CFU-E/BFU-E cell formation, and this result was associated with an increased number of apoptotic CD34+ erythroid/myeloid precursor cells. Administration of intra-uterine transfusion with washed RBCs was effective in improving fetal anaemia. CONCLUSIONS: Anti-CD36 antibodies may cause anaemia and trigger HF through apoptosis of CD34+ erythroid/myeloid precursor cells. However, the contribution of other cells must also be taken into account.

Metagenomic analysis of potential pathogens from blood donors in Guangzhou, China.

OBJECTIVES: This study aimed to identify the emerging/reemerging pathogens in blood donation samples. BACKGROUND: A metagenomic analysis has previously been used to look for pathogens but in this study, the relationship with aminotransferase (ALT) is described. METHODS/MATERIALS: Excluding samples reactive to hepatitis B virus, hepatitis C virus, human immunodeficiency syndrome virus or syphilis and plasma samples were stratified into three groups of ALT levels (IU/L): A ≤ 50, B 51 to 69 and C ≥ 70, respectively. Each group was mixed in a pool of 100 samples, from which DNA and cDNA libraries were established for next generation sequencing and analysis. Pathogens of interest were identified by immunoassays, nested-polymerase chain reaction, phylogenetic analysis and pathogen detection in follow-up donors. RESULTS: Several new or reemerging transfusion-transmitted pathogens were identified; Streptococcus suis, Babesia species and Toxoplasma gondii were found in the three ALT groups, Epstein-Barr virus (EBV) only in group C. Ten S. suis nucleic acid positive samples were detected, all closely phylogenetically related to reference strains. A donor in group A carried both S. suis genome and specific IgM in follow-up samples. This strain was identified as nontoxic S. suis. Five samples contained a short fragment of Babesia species SpeI-AvaI gene, while T. gondii was identified in 20 samples as a short fragment of 18S rDNA gene. In group C, two samples contained EBV genome. CONCLUSIONS: Blood donations that contained S. suis, Babesia species and T. gondii sequences might represent potential transfusion risks. EBV, a potential cause of elevated ALT, was detected. Metagenomic analysis might be a useful technology for monitoring blood safety.

Effective methods for reactivating inactive blood donors: a stratified randomised controlled study.

BACKGROUND: Recruiting of sufficient numbers of donors of blood products is vital worldwide. In this study we assessed the efficacy and cost-effectiveness of telephone calls and SMS reminders for re-recruitment of inactive blood donors. METHODS: This single-centre, non-blinded, parallel randomised controlled trial in Guangzhou, China included 11,880 inactive blood donors whose last donation was between January 1 and June 30, 2014. The donors were randomly assigned to one of two intervention groups (telephone call or short message service [SMS] communications) or to a control group without intervention. SMS messages with altruistic appeal were adopted in the SMS group; in addition to altruistic appeal, reasons for deferral of blood donation were also asked in the telephone group. All participants were followed up for 1 year. The primary outcome was re-donation rate, and rates in different groups were compared by intention-to-treat (ITT) analysis and estimation of the average treatment effect on the treated (ATT). Secondary outcomes were the self-reported deterrents. Other outcomes included the re-donation interval, and the incremental cost-effectiveness ratio (ICER) of telephone calls and SMS reminders on re-recruitment. RESULTS: ITT analysis revealed no significant differences in the re-donation rate among the three groups. ATT estimations indicated that among compliers, telephone calls significantly increased re-donation compared to both SMS reminders and no intervention. Donor return behaviour was positively associated with receiving reminders successfully, being male, older age, and previous donation history. The SMS reminder prompted donors to return sooner than no reminder within 6 months, and according to ICER calculations, SMS reminders were more cost-effective than telephone calls. Donors reported time constraints as the most main causes of self-deferral in the telephone group, and altruistic appeal had a positive effect on these donors. CONCLUSIONS: Interventions to reactivate inactive blood donors can be effective, with telephone calls prompting more donors to return but at a greater cost than SMS messages. SMS reminder with altruistic appeal can urge donors to re-donate sooner within 6 months than no reminder. TRIAL REGISTRATION: NCT03366441 (Reactivation of Inactive Blood Donors). Retrospectively registered 4 December 2017.

Association of HLA-DQB1*03:01 and DRB1*11:01 with spontaneous clearance of hepatitis C virus in Chinese Li ethnicity, an ethnic group genetically distinct from Chinese Han ethnicity and infected with unique HCV subtype.

Specific human leukocyte antigen (HLA) class I and class II alleles have been associated with spontaneous clearance or persistent infection of hepatitis C virus (HCV), which seemed to be restricted by the host's ethnicity and viral genotype. Recently we reported a high prevalence and spontaneous clearance rate of HCV in a cohort of Chinese Li ethnicity who were infected with new variants of HCV genotype 6. In this study, we found that the distribution of HLA class I and class II alleles in HCV infected individuals of Chinese Li ethnicity (n = 143) was distinct from that of Chinese Han ethnicity which was reported in our previous study. HLA-DRB1*11:01 and DQB1*03:01 were more prevalent in Chinese Li subjects who cleared HCV spontaneously than those who were chronically infected (P = .036 and P = .024, respectively), which were consistent with our previous report regarding the Chinese Han population. Multivariate logistic regression analysis showed that DQB1*03:01 (odds ratio = 3.899, P = .017), but not DRB1*11:01, associated with HCV spontaneous clearance, independent of age, sex, and IFNL3 genotype. Because DQB1*03:01 and DRB1*11:01 were tightly linked because of linkage disequilibrium, our results clearly supported the associations of these two alleles with HCV spontaneous clearance in Chinese Li as well as Han ethnicity.

Characterization of monocytic and granulocytic subsets of myeloid-derived suppressor cells in blood donors with occult hepatitis B virus infection.

Myeloid-derived suppressor cells (MDSCs) accumulate from many diseases. MDSCs are rarely explored in occult hepatitis B virus infection (OBI). The frequency of monocytic MDSCs (M-MDSCs) and granulocytic MDSCs (G-MDSCs) in OBI carriers was analyzed for correlation with clinical parameters, which was no different between OBI and healthy individuals, whereas the frequency of M-MDSCs but G-MDSCs in OBI was significantly lower than that observed in chronic hepatitis B carriers (0.4% vs 0.7%, P = 0.0004). The frequency of MDSCs was not correlated with clinical parameters and viral load of OBI, suggesting that the absence of HBsAg in OBI carriers might not induce the accumulation of MDSCs.