Cost-benefit analysis of serological and nucleic acid testing for hepatitis B virus in blood donors in southern China.

BACKGROUND: Most Chinese blood centers have implemented mini pool (MP) HBV nucleic acid testing (NAT) together with HBsAg ELISA in routine blood donor screening for HBV infection since 2015, and a few centers upgraded MP to individual donation (ID) NAT screening recently, raising urgent need for cost-benefit analysis of different screening strategies. In an effort to prevent transfusion-transmitted infections (TTIs) for HBV, cost-benefit analyses of three different screening strategies: HBsAg alone, HBsAg plus MP NAT and HBsAg plus ID NAT were performed in blood donors from southern China where HBV infection was endemic. METHODS: MP-6 HBV NAT and ID NAT were adopted in parallel to screen blood donors for further comparative analysis. On the basis of screening data and the documented parameters, the number of window period (WP) infection, HBV acute infection, chronic hepatitis B infection (CHB) and occult hepatitis B infection (OBI) was evaluated, and the potential prevented HBV TTIs and benefits of these three strategies were predicted based on cost-benefit analysis by an estimation model. RESULTS: Of 132,323 donations, the yield rate for HBsAg-/DNA + screened by ID NAT (0.12%) was significantly higher than that by MP NAT (0.058%, P < 0.05). Furthermore, the predicted transfusion-transmitted HBV cases prevented was 1.25 times more by ID NAT compared to MP-6 NAT. The cost-benefit ratio of the universal HBsAg screening, HBsAg plus ID NAT and HBsAg plus MP NAT were 1:58, 1:27 and 1:22, respectively. CONCLUSIONS: Universal HBsAg ELISA screening in combination with HBV ID NAT or MP-6 NAT strategies was highly cost effective in China. To further improve blood safety, HBsAg plus HBV DNA ID NAT screening should be considered in HBV endemic regions/countries.

Identification and validation of ferroptosis-related genes in patients infected with dengue virus: implication in the pathogenesis of DENV.

Ferroptosis, an iron-dependent form of regulated cell death, has been associated with many virus infections. However, the role of ferroptosis in dengue virus (DENV) infection remains to be clarified. In our study, a dengue fever microarray dataset (GSE51808) of whole blood samples was downloaded from the Gene Expression Omnibus (GEO), and a list of ferroptosis related genes (FRGs) was extracted from the FerrDb. We identified 37 ferroptosis-related differentially expressed genes (FR-DEGs) in DENV-infected patient blood samples compared to healthy individuals. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses as well as protein-protein interaction (PPI) network of FR-DEGs revealed that these 37 FR-DEGs were mainly related to the C-type lectin receptor and p53 signaling pathway. Nine out of the 37 FR-DEGs (HSPA5, CAV1, HRAS, PTGS2, JUN, IL6, ATF3, XBP1, and CDKN2A) were hub genes, of which 5 were validated by qRT-PCR in DENV-infected HepG2 cells. Finally, using miRNA-mRNA regulatory network, we identified has-miR-124-3p and has-miR-16-5p as the most critical miRNAs in regulating the expression of these hub genes. In conclusion, our findings demonstrated that 5 FR-DEGs, JUN, IL6, ATF3, XBP1, and CDKN2A, and two miRNAs, has-miR-124-3p and has-miR-16-5p may implicate an essential role of ferroptosis in DENV infection, and further studies are warranted to explore the underlying mechanisms.

Severe Acute Respiratory Syndrome Coronavirus 2 Infection and Blood Safety.

Since the outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), it has spread rapidly around the world and caused a serious global social crisis. During the epidemic, the blood collection and supply industry have been greatly impacted, due to the sharply dropped blood donors and transfusion transmission risk of SARS-CoV-2. Many infected individuals are asymptomatic and they may donate blood without awareness of the infection or before symptoms appear. In addition, viral RNAs have been detected in the blood of some patients infected with SARS-CoV-2. Although no infectious SARS-CoV-2 virus was found in the blood nor the blood components, there is a risk of transmission through blood transfusion which may endanger blood safety, especially during the pandemic period. This review briefly introduces the biological characteristics, epidemiology of SARS-CoV-2, with a particular focus on SARS-CoV-2 infection and blood safety.

[A novel CD36 mutation T538C (Trp180Arg) results in CD36 deficiency and establishment of a genotyping method for the novel mutation based on sequence-specific primer PCR].

OBJECTIVE: To explore the molecular basis for a CD36 deficiency individual and distribution of CD36 gene mutation in Guangxi population. METHODS: A female individual was studied. CD36 phenotype was detected by monoclonal antibody immobilization of platelet antigens assay (MAIPA) and flow cytometry (FCM). The coding regions of the CD36 gene were sequenced. A DNA-based polymerase chain reaction-sequence specific primer (PCR-SSP) assay was used to verify the identified mutation. Cell lines expressing the mutant and wild-type CD36[CD36(MT) and CD36(WT)] were established, with the expression of CD36 determined by Western blotting. The distribution of CD36 gene mutation was investigated among 1010 unrelated individuals with the PCR-SSP assay. RESULTS: Both MAIPA and FCM assays showed that the patient had type II CD36 deficiency. DNA sequencing showed that she has carried a heterozygous mutation T538C (Trp180Arg) in the exon 6 of CD36. Sequencing of cDNA clone confirmed that there was a nucleotide substitution at position 538 (538T>C). Western blotting also confirmed that the CD36 did not express on the CD36(MT) cell line that expressed the 538C mutant, but did express on the CD36(WT) cell line. The novel CD36 mutation T538C was further verified with 100% concordance of genotyping results by DNA-based PCR-SSP assay and 1010 unrelated individuals. No CD36 538C allele was detected among the 1010 individuals. CONCLUSION: This study has identified a novel CD36 mutation T538C(Trp180Arg)(GenBank: HM217022.1), and established a genotyping method for the novel sequence-specific primer PCR. The novel mutation is rare in Guangxi and can cause type II CD36 deficiency.

Role of Exosomal Modulation of Macrophages in Liver Fibrosis.

Exosomes are 60-120 nm diameter double-membrane lipid organelles discharged by cells. Various studies have shown that exosomes exert multiple functions in both physical and diseased processes, such as intercellular information exchange, immune response, and disease progression. Repeated chronic injury to the liver often leads to inflammation and liver fibrosis (LF), a disorder that, if unchecked, may progress to cirrhosis, liver failure, portal hypertension, and even hepatocellular carcinoma. As an essential component of host innate immunity against pathogen invasion, macrophages play an important role in modulating inflammation homeostasis by finely tuning the polarization process of macrophages into either M1 or M2 subtypes in response to different microenvironments. As a critical contributor to the inflammation process, macrophages also play a complex and instrumental function in the progression of LF. This review focuses on recent advancements in the role of macrophage-associated exosomes implicated in LF, including macrophage-released exosomes and macrophage-targeted exosomes. In addition, the progress made in exosome-based antifibrotic therapy by in vivo and in vitro studies is also highlighted.

Establishment of a Cleavage-Based Single-Plasmid Dual-Luciferase Surrogate Reporter for the Cleavage Efficiency Evaluation of CRISPR-Cas12a Systems and Its Primary Application.

CRISPR-Cas technology is a widely utilized gene-editing tool that involves gRNA-guided sequence recognition and Cas nuclease-mediated cleavage. The design and evaluation of gRNA are essential for enhancing CRISPR/Cas editing efficiency. Various assays such as single-strand annealing, in vitro cleavage, and T7 endonuclease I (T7EI) are commonly used to assess gRNA-mediated Cas protein cleavage activity. In this study, a firefly luciferase and Renilla luciferase co-expressed and a cleavage-based single-plasmid dual-luciferase surrogate reporter was built to evaluate the gRNA-mediated Cas12a cleavage efficiency. The cleavage activities of CRISPR-Cas12a can be quantitatively determined by the recovery degree of firefly luciferase activity. The cleavage efficiency of CRISPR-Cas12a can be quantitatively measured by the recovery of firefly luciferase activity. By using this system, the cleavage efficiency of CRISPR-Cas12a on hepatitis B virus (HBV)/D expression plasmid was evaluated, revealing a negative correlation between gRNA cleavage efficiency and HBV gene expression measured using an enzyme-linked immunosorbent assay. This simple, efficient, and quantifiable system only requires the dual-luciferase vector and CRISPR-Cas12a vector, making it a valuable tool for selecting effective gRNAs for gene editing.

Xanthomonas campestris pv. campestris possesses a single gluconeogenic pathway that is required for virulence.

Disruption of ppsA, a key gene in gluconeogenesis, of Xanthomonas campestris pv. campestris resulted in the failure of the pathogen to grow in medium with pyruvate or C4-dicarboxylates as the sole carbon source and a significant reduction in virulence, indicating that X. campestris pv. campestris possesses only the malic enzyme-PpsA route in gluconeogenesis, which is required for virulence.