SIRT2 regulates high mobility group protein B1 nucleoplasmic shuttle and degradation via deacetylation in microglia.

High mobility group protein B1 (HMGB1) acts as a pathogenic inflammatory response to mediate ranges of conditions such as epilepsy, septic shock, ischemia, traumatic brain injury, Parkinson's disease, Alzheimer's disease and mass spectrometry. HMGB1 promotes inflammation during sterile and infectious damage and plays a crucial role in disease development. Mobilization from the nucleus to the cytoplasm is the first important step in the release of HMGB1 from activated immune cells. Here, we demonstrated that Sirtuin 2 (SIRT2) physically interacts with and deacetylates HMGB1 at 43 lysine residue at nuclear localization signal locations, strengthening its interaction with HMGB1 and causing HMGB1 to be localized in the cytoplasm. These discoveries are the first to shed light on the SIRT2 nucleoplasmic shuttle, which influences HMGB1 and its degradation, hence revealing novel therapeutic targets and avenues for neuroinflammation treatment.

The role of receptors in the cross-species spread of coronaviruses infecting humans and pigs.

The pandemic caused by SARS-CoV-2, which has proven capable of infecting over 30 animal species, highlights the critical need for understanding the mechanisms of cross-species transmission and the emergence of novel coronavirus strains. The recent discovery of CCoV-HuPn-2018, a recombinant alphacoronavirus from canines and felines that can infect humans, along with evidence of SARS-CoV-2 infection in pig cells, underscores the potential for coronaviruses to overcome species barriers. This review investigates the origins and cross-species transmission of both human and porcine coronaviruses, with a specific emphasis on the instrumental role receptors play in this process.

Exploring the modulatory impact of isosakuranetin on Staphylococcus aureus: Inhibition of sortase A activity and α-haemolysin expression.

The ubiquity of methicillin-resistant Staphylococcus aureus (MRSA) and the mounting prevalence of antibiotic resistance necessitate the identification of novel therapeutic approaches to reduce the selective pressure of antibiotics. Targeting bacterial virulence factors, such as the pivotal Sortase A (SrtA) in S. aureus for adhesion and invasion, and the salient toxin α-Hemolysin (Hla), offers a sophisticated approach to attenuate pathogenicity without bacterial elimination. Herein, we report the discovery of a flavonoid, isosakuranetin, which inhibits the activity of S. aureus SrtA. A fluorescence resonance energy transfer assay revealed that isosakuranetin exhibited a low IC50 of 21.20 µg/mL. Furthermore, isosakuranetin significantly inhibited SrtA-related virulence properties, such as bacterial adhesion to fibrinogen, biofilm formation, and invasion of A549 cells. We employed fluorescence quenching and molecular docking to determine the interactions between isosakuranetin and SrtA, revealing the key amino acid sites for binding. Importantly, isosakuranetin inhibited the haemolytic activity of S. aureus in vitro at a concentration of 32 µg/mL. Moreover, isosakuranetin effectively suppressed the transcription and expression of Hla in a dose-dependent manner and regulated the transcription of RNAIII, the upstream operator of Hla. Notably, isosakuranetin demonstrated in vivo efficacy in a mouse model of S. aureus-induced pneumonia by significantly improving survival rates and reducing lung damage. This is a valuable finding, as isosakuranetin's dual inhibitory effects on SrtA and haemolytic activity, as well as its anti-virulence activity against MRSA, make it an excellent candidate for therapeutic development.

Isovitexin Protects Mice from Methicillin-Resistant Staphylococcus aureus-Induced Pneumonia by Targeting Sortase A.

The rise of methicillin-resistant Staphylococcus aureus (MRSA) has resulted in significant morbidity and mortality, and clinical treatment of MRSA infections has become extremely difficult. Sortase A (SrtA), a virulence determinant that anchors numerous virulence-related proteins to the cell wall, is a prime druggable target against S. aureus infection due to its crucial role in the pathogenicity of S. aureus. Here, we demonstrate that isovitexin, an active ingredient derived from a variety of traditional Chinese medicines, can reversibly inhibit SrtA activity in vitro with a low dose (IC50=24.72 µg/ml). Fluorescence quenching and molecular simulations proved the interaction between isovitexin and SrtA. Subsequent point mutation experiments further confirmed that the critical amino acid positions for SrtA binding to isovitexin were Ala-92, Ile-182, and Trp-197. In addition, isovitexin treatment dramatically reduced S. aureus invasion of A549 cells. This study shows that treatment with isovitexin could alleviate pathological injury and prolong the life span of mice in an S. aureus pneumonia model. According to our research, isovitexin represents a promising lead molecule for the creation of anti-S. aureus medicines or adjuncts.

Identification of host cell proteins that interact with the M protein of Pigeon paramyxovirus type 1.

Pigeon paramyxovirus type 1 (PPMV-1) belongs to the avian paramyxovirus type 1 group of viruses, which can cause tremors, torticollis, and respiratory signs in domestic and wild pigeons. The M protein of PPMV-1 is a multifunctional structural protein. It not only helps in the assembly, budding, and positioning of the virus but also inhibits the host's immune response and promotes replication of the virus in the host. In this study, the GST pull-down method was used to screen host proteins that interact with PPMV-1 M protein, and then mass spectrometry (MS) was used to analyse the screened host proteins. Enrichment analysis of the differentially expressed genes showed that the 77 screened proteins were highly associated with the gene ontology categories: protein synthesis, metabolism, and cell signalling pathway transduction. We selected NIMA-related kinase 7 (NEK7) as the candidate protein for co-localization analysis and co-immunoprecipitation verification. The results revealed that PPMV-1 M protein interacts with NEK7 of the host cell. This interactome study of PPMV-1 M protein will serve to clarify its function during viral replication and will provide a crucial theoretical basis for studying the pathogenic mechanism of PPMV-1.

Antibacterial, Antibiofilm, and Antioxidant Activity of Polysaccharides Obtained from Fresh Sarcotesta of Ginkgo biloba: Bioactive Polysaccharide that Can Be Exploited as a Novel Biocontrol Agent.

Staphylococcus aureus (S. aureus) biofilm plays an important role in the persistence of chronic infection due to its resistance to antibiotics. Because of their functional diversity, active polysaccharide is increasingly being applied as a biocontrol agent to inhibit the formation of biofilm by pathogens. In this study, a new polysaccharide, GBSPII-1, isolated from the fresh sarcotesta of Ginkgo biloba L. (G. biloba) was characterized and its effect on antibiofilm formation of S. aureus was examined in vitro. High-Performance Liquid Chromatography (HPLC) analysis showed that GBSPII-1 is an acidic heteropolysaccharide composed of mannose, rhamnose, glucose, glucuronic acid, and galacturonic acid. GBSPII-1 demonstrated a molecular weight of 34 kDa and may affect the accumulation of polysaccharide intercellular adhesion (PIA) by inhibiting icaA, icaB, icaC, and icaD gene expression at subinhibitory concentrations. Under 10 g/L, GBSPII-1 showed an antioxidant effect on the inhibition rate of H2O2-induced erythrocyte hemolysis and the scavenging rate of DPPH radicals was 76.5 ± 0.5% and 89.2 ± 0.26%, respectively. The findings obtained in this study indicate that GBSPII-1 has antibacterial effect, is a possible source of natural antioxidants, and may be a potential biocontrol agent for the design of new therapeutic strategies for biofilm-related S. aureus infections.

Corrigendum to: Emergence and evolution of highly pathogenic porcine epidemic diarrhea virus by natural recombination of a low pathogenic vaccine isolate and a highly pathogenic strain in the spike gene.

[This corrects the article DOI: 10.1093/ve/veaa049.].

Emergence and evolution of highly pathogenic porcine epidemic diarrhea virus by natural recombination of a low pathogenic vaccine isolate and a highly pathogenic strain in the spike gene.

Outbreaks of a new variant of porcine epidemic diarrhea virus (PEDV) at the end of 2010 have raised interest in the mutation and recombination of PEDV. A PEDV strain (CN/Liaoning25/2018) isolated from a clinical outbreak of piglet diarrhea contained a 49-bp deletion in the ORF3 gene. This deletion is considered a genetic characteristic of low pathogenic attenuated vaccine strains. However, CN/Liaoning25/2018 was highly pathogenic. Complete genome sequencing, identity analysis, phylogenetic tree construction, and recombination analysis showed that this virus was a recombinant strain containing the Spike (S) gene from the highly pathogenic CN/GDZQ/2014 strain and the remaining genomic regions from the low pathogenic vaccine isolate SQ2014. Histopathology and immunohistochemistry results confirmed that this strain was highly pathogenic and indicated that intestinal epithelial cell vacuolation was positively correlated with the intensity and density of PEDV antigens. A new natural recombination model for PEDV was identified. Our results suggest that new highly pathogenic recombinant strains in the field may be generated by recombination between low pathogenic attenuated live PEDV vaccines and pathogenic circulating PEDV strains. Our findings also highlight that the 49-bp deletion of the ORF3 gene in low pathogenic attenuated vaccine strains will no longer be a reliable standard to differentiate the classical vaccine attenuated from the field strains.

Cinnamaldehyde inhibits type three secretion system in Salmonella enterica serovar Typhimurium by affecting the expression of key effector proteins.

The increasing understanding of bacterial pathogenesis has revealed many new targets for the development of non-traditional antibacterial drugs. Interference with bacterial virulence has become a new strategy to treat bacteria-mediated diseases. As an important food-borne pathogen, Salmonella enterica serovar Typhimurium uses type III secretion system (T3SS) to facilitate invasion of host cells. In this study, we identified cinnamaldehyde as a Salmonella pathogenicity island 1 (SPI-1) inhibitor which blocks the secretion of several SPI-1 associated effector proteins and consequently exhibits a strong inhibitory effect on SPI-1-mediated invasion of HeLa cells. Further study revealed that cinnamaldehyde significantly reduced the transcription of some SPI-1 genes, such as sipA and sipB, in S. Typhimurium by affecting multiple SPI-1 regulator genes. In an animal infection model, cinnamaldehyde effectively protected infected mice against S. Typhimurium-induced mortality and pathological damages. In summary, this study presented an effective SPI-1 inhibitor, cinnamaldehyde, which reduces the expression of SPI-1 effector proteins by regulating the transcription of main regulator genes.

The evolution and molecular characteristics of H9N2 avian influenza viruses in Jiangxi of China.

To understand the evolution and molecular characteristics of Jiangxi H9N2 viruses, we isolated 17 viruses in 2011 and analyzed their characteristics. Phylogenetic analyses revealed that their hemagglutinin genes originate from JS/1/00-like sublineage, neuraminidase genes originate from BJ/94-like sublineage, PB1, PA, NP, and NS genes all come from SH/F/98-like sublineage, PB2 genes originate from ST/163/04-like sublineage, while M genes come from G1-like sublineage. Genotype analysis showed that our isolates were classified as genotype 57. Molecular analyses indicated that our strains contained specific sites characteristic of low-pathogenic viruses. The current study once again highlights the necessity for continued surveillance of novel H9N2 viruses.

Extraction, preliminary characterization and antioxidant properties of polysaccharides from the testa of Salicornia herbacea.

Response surface methodology and central composite design based on single-factor experiments were used to optimize the extraction parameters (i.e., extraction time, extraction temperature, and solid-liquid ratio) of polysaccharides from the testa of Salicornia herbacea (STP). The optimal conditions included a liquid-solid ratio of 57:1 (volume/mass), an extraction time of 300min and an extraction temperature of 87°C. Under these conditions, the maximal yield of crude STP was 1.30±0.06%, which agreed with model predictions. Preliminary characterization of the purified acidic polysaccharide (STP II-1) by high performance liquid chromatography indicated that it was composed mainly of d-mannose, d-rhamnose, d-glucose, d-galactose, d-arabinose, glucuronic acid and galacturonic acid. The antioxidant capacity of STP II-1 was analyzed by monitoring both the scavenging rate of the 2,2-diphenyl-1-picrylhydrazyl free radical and inhibition rate of H2O2-induced erythrocyte hemolysis.

Lactobacillus casei regulates differentiation of Th17/Treg cells to reduce intestinal inflammation in mice.

In order to study the ability of Lactobacillus casei to ameliorate murine enteritis, 18 mice were randomly divided into 3 groups: the enteritis group, intervention group, and control group. The interleukin (IL)-6 and transforming growth factor-ß (TGF)-ß content in mouse peripheral blood and duodenum was detected using an enzyme-linked immunosorbent assay (ELISA). The number of CD4+CD25+Foxp3+ T-regulatory cells (Tregs) and CD4+IL-17A+ Th17 cells in the mesenteric lymph nodes (MLN) and spleen were detected using flow cytometry, and quantitative reverse transcription polymerase chain reaction (PCR) and western blot analysis were used to measure Foxp3 and retinoid-related orphan receptor-γ (RORγt) mRNA and protein expression in the MLN. Histological changes in the duodenum were observed. Results indicate that in the intervention group, IL-6 content in mouse peripheral blood and duodenum was significantly lower than in the enteritis group (P < 0.05), while TGF-ß content was significantly increased compared to the enteritis group (P < 0.05). For the intervention group, the percentages of CD4+CD25+Foxp3+ Tregs in spleen and MLN were increased (P < 0.05), while the percentages of CD4+IL-17A+ Th17 cells were decreased compared to the enteritis group (P < 0.05). The expression of Foxp3 mRNA and protein in the intervention group was higher than in the enteritis group, while RORγt mRNA and protein were significantly lower (P < 0.05). After mice in the enteritis group were treated with L. casei, duodenal inflammation was relieved. This study demonstrated that L. casei could have possible implications for the enterotoxigenic Escherichia coli (ETEC) induced intestinal inflammation by regulating the ratio imbalance of Th17/Treg cells.

Afin d'étudier la capacité de Lactobacillus casei à soulager l'entérite murine, 18 souris ont été réparties de manière aléatoire en trois groupes : le groupe entérite, le groupe intervention, et le groupe témoin. Les quantités d'interleukine (IL)-6 et de facteur de croissance transformant ß (FCT-ß) dans le sang périphérique et le duodénum de souris furent détectées à l'aide d'une épreuve immunoenzymatique (ELISA). Les cellules T régulatrices (Tregs) CD4+CD25+Foxp3+ et les cellules CD4+IL-17A+ Th17 dans les noeuds lymphatiques mésentériques (NLM) et la rate ont été détectées et dénombrées par cytométrie en flux, et réaction d'amplification en chaîne quantitative avec la transcriptase réverse, et l'analyse par immunobuvardage fut utilisée afin de mesurer l'expression de l'ARNm et de la protéine Foxp3 et du récepteur orphelin γ apparenté au rétinoïde (RORγt) dans les NLM. Les changements histologiques dans le duodénum ont été observés. Les résultats indiquent que dans le groupe intervention, le contenu en IL-6 dans le sang périphérique et le duodénum était significativement moindre que dans le groupe entérite (P < 0,05), alors que le contenu en FCT-ß était augmenté de manière significative comparativement au groupe entérite (P < 0,05). Pour le groupe intervention, les pourcentages de Tregs CD4+CD25+Foxp3+ dans la rate et le NLM étaient augmentés (P < 0,05), alors que les pourcentages de cellules CD4+IL-17A+ Th17 étaient diminués comparativement au groupe entérite (P < 0,05). L'expression de l'ARNm et de la protéine Foxp3 dans le groupe intervention était plus élevée que dans le groupe entérite, alors que l'expression de l'ARNm et de la protéine RORγt était significativement moindre (P < 0,05). Suite au traitement des souris du groupe entérite avec L. casei, l'inflammation duodénale était résorbée. La présente étude a démontré que L. casei pourrait avoir des implications possibles dans l'inflammation intestinale induite par Escherichia coli entérotoxinogène en régulant le débalancement du ratio de cellules Th17/Treg.(Traduit par Docteur Serge Messier).

Preparation and evaluation of MS2 bacteriophage-like particles packaging hepatitis E virus RNA.

Hepatitis E virus (HEV) is the pathogen causing hepatitis E (HE). It arouses global public health concern since it is a zoonotic disease. The objective of this letter is to report a cost-effective internal control prepared for monitoring procedures of HEV reverse transcriptase (RT)-PCR detection. A selected conserved HEV RNA fragment was integrated into the downstream of the truncated MS2 bacteriophage genome based on Armored RNA technology. The resulting MS2-HEV gene harbored by the pET-28b-MS2-HEV plasmid was transformed into E. coli BL21(DE3) for expression analysis by SDS-PAGE. The expression products were purified and concentrated by ultrasonication and ultrafiltration separation. The morphology and stability properties of the virus-like particles (VLPs) were evaluated by electron microscopy scanning and nuclease challenges, respectively. SDS-PAGE results showed that the constructed MS2-HEV gene expressed efficiently and the purity of the VLPs was highly consistent with the result in electron microscopy. Stability evaluation results demonstrated that the prepared VLPs exhibited strong resistance to DNase I and RNase A attacks and also performed long-lasting protection of coated HEV RNA for at least 4 months at -20°C. These data revealed that the prepared VLPs meet the basic requirements of use as internal control material in the HEV RNA amplification assay.

A recombinant polypeptide from velvet antler of Cervus nippon Temminck exhibits similar immunomodulatory effects as its natural counterpart.

CONTEXT: Velvet antler (VA) is recognized as one of the most important Chinese traditional medical herbs. To date, the immunoactivity of the single component of VA is rarely studied though its compound extracts have been well analyzed. OBJECTIVE: The current study was designed to evaluate the immunomodulatory effects of a recombinant polypeptide (rVAP32) based on the VA of the sika deer by comparison with its natural counterpart (nVAP32). MATERIALS AND METHODS: Splenocytes proliferation and NK-cell cytotoxicity assay was evaluated by the WST-8 colorimetric method. CD4+/CD8+ cell subpopulations regulation was screened by the flowcytometry method and the Th1 or Th2-related cytokine production was measured by ELISA. RESULTS: In vitro tests showed that both rVAP32 and nVAP32 could significantly stimulate splenocytes proliferation and enhance the NK-cell cytotoxicity and CD4+/CD8+ cell subpopulations when compared with the irrelevant peptide and blank control groups. Also, they demonstrated a significant capacity in up- and down-regulating the expression of Th1- and Th2-related cytokines, respectively. There is no statistically significant difference found between the rVAP32 tested group and nVAP32 control group. DISCUSSION AND CONCLUSION: The results obtained herein indicate that rVAP32 has the similar immunomodulatory effects on the immune system of mice as its counterpart nVAP32 in vitro. The further test in vivo is qualified and rVAP32 is promised for developing a new biopharmaceutical product as a substitute for nVAP32.

Development and evaluation of a RT-LAMP assay for rapid detection of hepatitis E virus from shellfish.

Hepatitis E virus (HEV) has becoming a well known zoonotic enteric pathogen and circulated widely inter human-animal-water-food. Generally, detection of the virus has relied on conventional reverse transcription-PCR (RT-PCR) and TaqMan/SYBR quantitative real-time RT-PCR (RT-qPCR), but these tools are usually disadvantages in time-consuming and expensive instruments required. In the present study, we report here on the development of a one-step single-tube reverse transcription-loop-mediated isothermal amplification (RT-LAMP) assay for rapid detection of HEV contamination in shellfish. The amplification is completed under the isothermal condition (63 °C) for 60 min, and can be visually evaluated by staining at a time in about 1h. In addition, a total of 315 shellfish (80 Anadara granosa, 115 Scapharca subcrenata and 120 Ruditapes philippinarum) collected monthly from the Jinzhou coastal estuary of China Bohai gulf were investigated for HEV contamination by the RT-LAMP compared with a standard RT-qPCR. It was found that genotype 4 HEV was detected in all three species of shellfish sampled using the RT-LAMP assay and was in accordance with RT-qPCR detection of HEV in shellfish. Summarily, our results indicate that the RT-LAMP is a rapid, specific, sensitive and reliable method. This method offers a new tool for the routine monitoring of HEV contamination in shellfish or its harvesting waters in field.

[Preparation and Characterization of Recombinant HEV RNA-loaded MS2 Bacteriophage Capsid by Armored RNA Technology].

The purpose of this study was to develop an effective control to be applied in hepatitis E virus(HEV)nucleic acid detection.Construction of an MS2/HEV gene was performed based on an "Armored RNA technology" protocol. The gene included a partial MS2 phage genome including the 5'UTR,the maturation protein, capsid protein and initiation site of the replicase and a partially conserved sequence derived from the HEV ORF2.The target genes were synthesized and amplified by PCR, and the purified target gene products subcloned into the pET-28 b prokaryotic expression vector to obtain the pET-28b-MS2/HEV recombinant plasmid. SDS-PAGE was used for expression analysis in E. coli BL21(DE3)cells harboring the pET-28b-MS2/HEV plasmid. Centrifugal ultrafiltration was adopted for the purification and concentration of recombinant HEV RNA-loaded MS2 Bacteriophage Capsid (rHEPC). The morphological identification of the particles was subsequently performed by scanning electron microscopy. Stability of the rHEPC particles were evaluated by challenging with different concentrations of DNase I and RNase A, and also evaluated for long-term storage based on RT-PCR verification. SDS-PAGE results showed that the target MS2/HEV gene could express efficiently in recombinant E. coli BL21(DE3)and RT-PCR results revealed that the designed HEV conserved gene sequence was successfully packaged into MS2phage-like or rHEPC particles. Stability evaluation showed that the prepared rHEPC particles exhibited strong resistance to degradation by DNase I and RNase A and long-lasting protection of coated HEV RNA for at least seven months when stored at-20℃.The prepared rHEPC particles in the present study meet the basic requirements to be used as a quality control material for routine HEV nucleic acid detection.

[Effects of temperature and pH on the growth of H1N1 subtype of influenza A virus by surface-enhanced Raman spectroscopy].

Surface enhanced Raman spectroscopy technology (SERS), using gold nanoparticles as a base, was developed for rapid and sensitive detection of virus strains. SERS can be used as a rapid and reliable method to distinguish the titers of viral replication. In the present study, we characterized H1N1 subtypes of influenza A virus strains in different conditions of pH or temperatures, while we analyzed data from SERS technology using gold nanoparticles as a base and cell cultures were employed to further confirm the data from virus strains. Origin8.0 was used to collect Raman spectra, smooth and homogenize data, and to contrast spectra. Our results indicated that the peaks of different virus strains in optimal environmental conditions (T=37 ℃/pH=7.2) reached ≥3 000. This criterion was verified by subsequent virological method. The present data indicate that the established SERS protocol can be used as a rapid and reliable method to distinguish the replication rate of virus, which can be further used in clinical samples.

Immunomodulatory effects of epicatechin-(2ß→O→7, 4ß→8)-ent-epicatechin isolated from Rhododendron spiciferum in vitro.

CONTEXT: Many traditional Chinese medicines (TCMs) can act as either immunosuppresants or immunostimulants, properties that have lead to their increasing use as immunomodulators in the treatment of disease. Recently, our lab successfully identified a dimer epicatechin-(2ß→O → 7, 4ß→8)-ent-epicatechin (EEE) from the chloroform extract of Rhododendron spiciferum. OBJECTIVE: To evaluate the immunomodulatory effects of EEE in vitro. MATERIALS AND METHODS: Splenocytes, peritoneal macrophages and peripheral blood mononuclear cells from BALB/c mice were incubated with different concentrations of EEE. RESULTS: EEE significantly stimulates splenocyte proliferation when administered either alone or in combination with concanavalin A (Con A), lipopolysaccharide (LPS), and Anti-CD3. EEE enhances the cytotoxicity of natural killer (NK) cells markedly and phagocytic function of macrophage. Moreover, we found that the levels of several helper T1 (Th1) cytokines, including interleukin-2 (IL-2), IL-12, interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) are significantly increased after EEE treatment, while the levels of Th2 cytokine IL-4 and IL-10 are significantly decreased. As a result, the ratio of Th1/Th2 is significantly increased in the presence of EEE. EEE also increased CD4 and CD8 cell populations. CONCLUSION: These results indicate that EEE exhibits immunomodulatory activity and suggests that this compound could be developed as a novel immunotherapeutic agent for treating cancer and other immune-mediated diseases.

Surveillance of hepatitis E virus contamination in shellfish in China.

BACKGROUND: Hepatitis E virus (HEV) has been confirmed to be a zoonotic virus of worldwide distribution. HEV contamination in the water environment has not been well examined in China. The objective of this study was to evaluate HEV contamination in shellfish in a coastal area of China. Such contamination would be significant for evaluating public health risks. METHODS: samples of three species shellfish were collected from thirteen points of estuarine tidal flats around the Bohai Gulf and screened for HEV RNA using an in-house nested RT-PCR assay. The detected HEV-positive samples were further verified by gene cloning and sequencing analysis. RESULTS: the overall HEV-positive detection rate is approximately 17.5% per kilogram of shellfish.  HEV was more common among S. subcrenata (28.2%), followed by A. granosa (14.3%) and R. philippinarum (11.5%). The phylogenetic analysis of the 13 HEV strains detected revealed that gene fragments fell into two known 4 sub-genotypes (4b/4d) groups and another unknown group. CONCLUSIONS: 13 different sub-genotype 4 HEVs were found in contaminated shellfish in the Bohai Gulf rim. The findings suggest that a health risk may exist for users of waters in the Bonhai area and to consumers of shellfish.  Further research is needed to assess the sources and infectivity of HEV in these settings, and to evaluate additional shellfish harvesting areas.

Oral immunization with recombinant hepatitis E virus antigen displayed on the Lactococcus lactis surface enhances ORF2-specific mucosal and systemic immune responses in mice.

Hepatitis E virus (HEV) as a recognized zoonotic pathogen has posed global burden on public health, which is exacerbated by lack of efficient vaccine. In this study, we constructed a recombinant (inaQ-ORF2 gene fusion) Lactococcus lactis (L. lactis) strain NZ3900 that expresses and displays the hepatitis E virus antigen ORF2 utilizing an ice uncleation protein-based anchor system. After oral vaccination of BALB/c mice, significantly higher levels of ORF2-specific mucosal IgA and serum IgG were detected and cellular immunity was also induced. These findings further support that L. lactis-based HEV antigen vaccines could be used for human and animal protection against infection.