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PEDV infection causes severe piglet mortality and threatens the global pig industry. However, the complex invasion mechanism of PEDV makes its prevention and control difficult.

Staphylococcus epidermidis strain CCSM0287 was isolated from healthy facial skin. The complete genome of CCSM0287 was sequenced using a combination of Pacific Biosciences (PacBio) RS II single-molecule real-time (SMRT) and Illumina sequencing. The assembled 2.5-Mbp genome consisted of one chromosome and three plasmids.

Staphylococcus capitis strain CCSM0123 was isolated from healthy facial skin. The complete genome of CCSM0123 was sequenced using a combination of Pacific Biosciences (PacBio) RS II single-molecule real-time (SMRT) and Illumina sequencing. The assembled 2.5-Mbp genome consisted of one chromosome and four plasmids.

10-Hydroxy-2-decenoic acid (10-HDA) is an α,β-unsaturated medium-chain carboxylic acid containing a terminal hydroxyl group. It has various unique properties and great economic value. We improved the two-step biosynthesis method of 10-HDA. The conversion rate of the intermediate product

Pseudorabies virus (PRV) was isolated from some human cases recently and the infected patients manifested respiratory dysfunction and acute neurological symptoms. However, no effective drug or vaccine, preventing the progression of PRV infection, is available. Nectin-1 was the only reported receptor for PRV cell entry both swine and human origin, representing an excellent target to block PRV infection, and especially its transmission from pigs to humans. A PRV-gD specific mAbs (10B6) was isolated from hybridomas and its neutralizing activities in vitro and in vivo were determined. 10B6 exhibited effective neutralizing activities in vitro with IC50 = 2.514 μg/ml and 4.297 μg/ml in the presence and absence of complement. And in vivo, 10B6 provided 100% protection against PRV lethal challenge with a dose of 15 mg/kg. Further, 10B6 could bind to a conserved epitope, 316QPAEPFP322, locating in gD pro-fusion domain, and finally blocks the binding of PRV-gD to nectin-1. Moreover, 10B6 showed an effective inhibition on PRV cell-attachment in a cell type-independent manner and could also block the virus spreading among cells. 10B6 exhibited effectively neutralizing activities to Chinese PRV variant strain in vitro and in vivo by blocking gD binding to nectin-1, implied both prophylactic and therapeutic interventions against PRV infections.

The notable improvement of China's wetland management policies over the last four decades prompted this study's goal to quantitatively analyze the transformation of China's coastal wetland policies from 1979 to 2022 by applying an institutional network analysis and policy text analysis. The results of the institutional network analysis revealed an administrative management transformation from a multidepartmental mode to an integrated management framework. Furthermore, the policy text analysis results revealed a change in policy priorities (from exploitation to protection) and management targets (from a single environmental element to a comprehensive ecosystem and further to collaborative governance). In addition, the overall outcome of this study instigated proposals for the improvement of future wetland policies on climate change, integrated planning, natural capital, and public participation. Hence, this study presents an example of wetland policy analysis based on a quantitative review, which we hope will also be valuable for other countries.

Lavender (Lavandula angustifolia Mill.) essential oil is renowned for its use in the treatment of insomnia and mental disorder diseases in folk medicine. Previous pharmacological studies have also shown that lavender essential oil displays sedative and hypnotic activities. However, the active ingredients and mechanism of lavender essential oil for sleep-improving effect remain unclear.This study investigates whether inhalation of different fractions of lavender essential oil can attenuate the sleep disturbances induced by combined anxiety and caffeine and explores the underlying mechanisms.Molecular distillation was applied to separate lavender essential oil into fractions containing different chemical components, and GC-MS was used to analyze the volatile compounds of lavender essential oil and its fractions. The elevated plus maze test, pentobarbital-induced sleep test, and neurotransmitters enzyme-linked immunosorbent assay were conducted to evaluate the anxiolytic and hypnotic effects of lavender essential oil and its fractions on mice suffering from sleep disorders.The results of behavioral tests indicated that lavender essential oil and its fractions (3%, v/v) exerted an ameliorating effect on sleep disturbances induced by anxiety and caffeine. The light fraction and heavy fractions exhibited complementary chemical composition, with the former enriched in linalool and trans-β-ocimene and the latter in linalyl acetate, lavandulyl acetate, trans-caryophyllene, etc. The light fraction contributed more to sleep maintenance, and the heavy fraction performed better at sleep initiation. The neurobiological parameters elucidated that the mechanism of lavender essential oil for sleep-improving was multifaceted, related to the GABAergic system, cholinergic system, histaminergic system, and monoamines in the limbic system. The heavy fraction shared a similar mechanism with the lavender essential oil, while the light fraction did not actively participate in the cholinergic system, histaminergic system, and dopaminergic system.Taken together, our results demonstrated that different fractions of lavender essential oil played different roles in ameliorating sleep disorders, and this may be credited to their compositional differences and the complicated interactions with the central nervous system. The results are informative for future investigations on the molecular level mechanisms and provide guidance for appropriate applications of lavender essential oil.

Recently, pseudorabies virus (PRV) was isolated from human cases, and infected patients presented with respiratory dysfunction and acute neurological symptoms. However, there was no available effective drug to prevent the progression of PRV infection. In the present study, we screened a stably Drosophila S2 cell line which can secretory express a novel type I IFNs-interferon delta 8 (IFN-δ8) and the yield was about 10 mg/L. After purification, recombinant IFN-δ8 was demonstrated to be acid-stable, heat-stable, and nontoxic to PK-15 and 3D4/21 cells. Antiviral effects of IFN-δ8 against PRV were tested in vitro. Our results showed both pre- and post-treatment, recombinant PoIFN-δ8 exerted a significant protective effect against PRV infection in PK-15 and 3D4/21 cells. In addition, PoIFN-δ8 remarkably increased the expression of eight IFN-stimulated genes (ISGs), including ISG15, OAS1, PKR, MX1, CH25H, IFITM1, IFITM2 and IFITM3, to resist virus infection. These findings highlight the significance of IFN-δ8 that might serve as an antiviral agent for the prevention of PRV infection, and maybe expand the potential function of IFN antiviral drugs in the future.

We report a new competitive lateral flow immunoassay (LFIA) for hapten detection, which uses antibodies to bind antigens from a sample and form a coloured immune complex due to artificial antigens conjugated with gold nanoparticles; these were intercepted with SPA. Here, 2,4-dichlorophenoxyacetic acid (2,4-D) and gentamicin (GM) were selected as model analytes. The visual limit of detection of the 2,4-D strip was 25 ng/mL in tap water; the GM strip was 3.13 ng/mL in milk. This approach exhibits more than a 40-fold lower detection limit for 2,4-D and 3.2-fold lower for GM, which is compared to traditional LFIA using the same reagents. This approach can accurately control the amount of antibody, protect the activity of antibody and enhance the detection signal, thus improving the sensitivity of the LFIA and providing more and more sensitive methods for the development of LFIAs. Highlights This study developed a new method of LFIA that could improve the sensitivity of LFIA without adding any reagent. The antibodies are unlabelled; thus, the immunological properties of the antibodies are not destroyed by antibody folding during the labelling process. Sufficient gold-labelled antigens ensure that each antibody bound to the test line can combine two gold nanoparticles, thereby amplifying the overall signal.

Metastasis is responsible for the poor prognosis of patients with colorectal cancer (CRC), and the role of aberrant expression of endoplasmic reticulum (ER) receptors in tumour metastasis has not been fully elucidated. The aim of the study is to ensure the role of ER-resident protein Sec62 in CRC metastasis and illuminate associated molecular mechanisms.Bioinformatics analysis, qRT-PCR, western blot and immunohistochemistry assays were performed to evaluate the expression level and clinical significance of Sec62 in CRC. The specific role of Sec62 in CRC was identified by a series of functional experiments. We conducted RNA sequencing and rescue experiments to analyse the differentially expressed genes and identified UCA1 as a novel pro-metastasis target of Sec62 in CRC. Besides, the efficacy of MAPK/JNK inhibitor or agonist on Sec62-mediated CRC metastasis was evaluated by trans-well and wound healing assays. Finally, luciferase reporter and ChIP assay were employed to further explore the potential mechanisms.The abnormally elevated expression of Sec62 predicted poor prognosis of CRC patients and facilitated malignant metastasis of CRC cells. Mechanistically, Sec62 enhanced UCA1 expression through activating MAPK/JNK signalling pathway. And the p-JNK activating ATF2 could transcriptionally regulate UCA1 expression. Furthermore, blocking or activating MAPK/JNK signalling with JNK inhibitor or agonist potently suppressed or enhanced Sec62 mediated CRC metastatic process.Our study reports for the first time that the Sec62/MAPK/ATF2 /UCA1 axis exists in CRC metastatic process, which could be a potential treatment target of metastatic CRC.

Background: Skin is the primary defense to human body from external exposure of harmful stimulation. Excessive and improper immune-regulation could cause chronic inflammation resulting in different skin diseases. Pingyin Rose is a well-known component of traditional Chinese medicine (TCM) because of its wide range of bioactivities and so do PREO.Aim: The present work aims to characterize the Pingyin rose essential oil (PREO) composition, investigate the beneficial effects of PREO on the skin inflammation in vitro and determine ligands for OR2AT4 in silico from PREO components.Materials and Methods: PREO was quantified by GC-MS and molecular docking was performed for OR2AT4 with top two components. HaCaT cells were induced with lipopolysaccharides (LPS) to study downregulation of oxidative stress and inflammation through NF-κB signaling. Result and Discussion: According to our results, Citronellal (54.28%) and geraniol (9.26%) are the principal compounds of PREO and both deemed to be potential ligand for OR2AT4. PREO could significantly reduce the expression of the TLR4-NF-κB pathway in LPS-induced HaCaT cells. PREO could also prevent LPS-mediated oxidative stress, including the increase of SOD and MDA, decrease of mRNA expression for inflammatory markers (TNF-α, IL-1β, IL-6, IL-8) and several genes involved in TLR4 pathway, that is also an evident for PREO as potential anti-inflammatory therapeutic. PREO also inhibits NF-κB p65 and IκB-α protein phosphorylation. Conclusion: Our findings revealed that PREO could decrease inflammatory protein expressions, possibly functioning with the reduction of oxidative stress and inflammatory cytokines via downregulating NF-κB pathway. PREO component can interact with OR2AT4 and paly roles in other physiological activities.

Li Shao,1 Sujing Jiang,1 Yan Li,2 Yanqin Shi,1,3 Man Wang,4 Ting Liu,1 Suzhen Yang,2 Laiji Ma1,3 1School of Perfume and Aroma Technology, Shanghai Institute of Technology, Shanghai, People’s Republic of China; 2R&D Innovation Center, Shandong Freda Biotech Co., Ltd, Jinan, Shandong, People’s Republic of China; 3The Oriental Beauty Valley Research Institute, Shanghai Institute of Technology, Shanghai, People’s Republic of China; 4Department of Nutrition, Shanghai Jiao Tong University Affiliated Sixth People’s Hospital South Campus, Shanghai, People’s Republic of ChinaCorrespondence: Laiji Ma, School of Perfume and Aroma Technology, Shanghai Institute of Technology, No. 100, Haiquan Road, Fengxian District, Shanghai, 201418, People’s Republic of China, Email laijima_sh@163.com Suzhen Yang, R&D Innovation Center, Shandong Freda Biotech Co., Ltd, No. 888, Xinluo Street, Lixia District, Jinan, Shandong, 250101, People’s Republic of China, Email 85844202@qq.comBackground: Late bedtime is a common form of unhealthy sleep pattern in adulthood, which influences circadian rhythm, and negatively affects health. However, little is known about the effect of regular late bedtime on skin characteristics, particularly on skin microbiome.Objective: To investigate the changes and effects of the regular late bedtime on skin physiological parameters and facial bacterial microbiome of 219 cases of Chinese women aged 18– 38 years living in Shanghai.Methods: Based on the Self-Evaluation Questionnaire, bedtime was categorized as 11:00 PM; thus, the volunteers were divided into early bedtime group (S0) and late bedtime group (S1). The physiological parameters of facial skin were measured by non-invasive instrumental methods, and the skin microbiome was analyzed by 16S rRNA high-throughput sequencing.Results: The skin physiological parameters of the late bedtime group exhibited significant decrease in skin hydration content, skin firmness (F4) and elasticity (R2), while TEWL, sebum and wrinkle significantly increased. The result indicated that late bedtime significantly impaired the integrity of skin barrier, damaged skin structure, and disrupted water–oil balance. Furthermore, the analysis of α-diversity, Sobs, Ace and Chao index were found to significantly decrease (P < 0.05) in the late bedtime group, suggesting that late bedtime reduced both the abundance and the diversity of facial bacterial microbiota. Moreover, the abundance of Pseudomonas increased significantly, while Streptococcus, Stenotrophomonas, Acinetobacter, Haemophilus, Actinomyces and Neisseria decreased significantly. In addition, Spearman correlation analysis revealed strong correlations between the microbiota and the physiological parameters. Notably, the abundance of Pseudomonas significantly positively correlated with skin firmness and elasticity, but significantly negatively correlated with skin hemoglobin content, melanin content and skin hydration.Conclusion: Bedtime is an important factor in maintaining skin health. Regular late bedtime not only damages the skin barrier and skin structure but also reduces the diversity and composition of facial bacterial microbiome.Keywords: sleep, late bedtime, skin biophysical property, skin barrier, skin microbiota

Foot and mouth disease virus (FMDV) is a highly contagious pathogen propagating among cloven-hoofed animals. As a major immunogenic protein, VP1 plays a pivotal role in the induction of neutralizing antibodies, which therefore is an ideal target for developing subunit vaccines. In current study, four prokaryotic expression clones (rV4C, rC4V, rV5F and rF5V) were constructed by fusing truncated calreticulin (CRT) (120–250 aa or 120–308 aa) at the N/C terminal of vp1 gene, and co-expressed with chaperone trigger factor 16 (Tf16) in E.coli, respectively. The soluble recombinant CRT-fused VP1 proteins could form into homogeneous reactive polymers with average hydrodynamic diameters around 100 nm according to the dynamic light scattering (DLS) data. Immunization of guinea pigs with 10 μg purified CRT-fused VP1 proteins induced high levels of antibodies against naked-VP1 through indirect ELISA. Sandwich ELISA showed that only rC4V could elicit the same level of antibody against FMD virus as commercial inactivated vaccine after booster. The lymphocyte cytokines secretion of immunized rC4V was higher than the other CRT-fused VP1 proteins in guinea pigs. These results showed that the soluble CRT-fused VP1 proteins, especially rC4V, expressed with Tf16 in E. coli might have potential to be used as subunit vaccine candidate against FMDV.

Visceral hypersensitivity (VH) is common in irritable bowel syndrome (IBS), and female patients are more likely to seek healthcare services for IBS-related abdominal pain. Oestrogen has been reported to mediate pain modulation via its receptor, and mast cells are known to participate in the development of visceral hypersensitivity. Our previous studies showed that the G-protein-coupled oestrogen receptor (GPER, also known as GPR30) was expressed by mast cells in human colonic tissues and was associated with IBS type and severity of visceral pain. However, whether GPER is involved in oestrogen-dependent visceral hypersensitivity via mast cell degranulation is still unknown. Rats were subjected to wrap partial restraint stress to induce visceral hypersensitivity and were ovariectomized (OVX) to eliminate the effects of oestrogen on visceral hypersensitivity. OVX rats were treated with oestrogen, an oestrogen receptor α and β antagonist (ICI 182.780), a GPER antagonist (G15) or a GPER agonist (G1), to evaluate the effects of oestrogen via its receptor. The colorectal distention test was performed to assess visceral sensitivity. Immunofluorescence studies were performed to evaluate GPER and mast cell tryptase co-expression. Mast cell number with degranulation was detected by specific staining. Mast cell tryptase expression in rat colon was also investigated by Western blot and immunohistochemistry. Substance P and histamine expression were examined by ELISA. GPER was expressed by the majority of tryptase-positive mast cells in the colonic mucosa. Stressed rats showed increased visceral sensitivity, increased mast cell degranulation, mast cell tryptase expression, and increased colon histamine levels. Ovariectomy reduced stress-induced VH in female rats and decreased mast cell degranulation, mast cell tryptase expression, and histamine levels, whereas oestrogen replacement reversed these effects. In OVX rats, the GPER antagonist G15 counteracted the enhancing effects of oestrogen on stress-induced VH, mast cell degranulation, mast cell tryptase, and histamine expression, whereas VH was preserved after treatment with ICI 182.780. On the other hand, pretreatment with the selective GPER agonist G1 at doses between 1 and 20 μg/kg significantly increased VH, mast cell tryptase, and histamine expression in OVX-stressed rats, mimicking the effects of oestrogen. GPER plays a pivotal role in the regulation of mast cell degranulation, mast cell tryptase expression, and histamine levels and contributes to the development of colonic hypersensitivity in a female rat model of IBS.

Background: The role of CARM1 in tumors is contradictory. It acts as an oncogene in most kinds of cancers while inhibits the progression of liver and pancreatic cancers. CARM1 has recently been reported to regulate autophagy, which is also context-dependent. However, the effect of CARM1 on gastric cancer has not been studied. We aimed to explore whether CARM1 was involved in the progression of gastric cancer by regulating autophagy.Methods: The clinical values of CARM1 and autophagy in gastric cancer were determined by immunohistochemistry and qRT-PCR. Transmission electron microscopy, immunofluorescence and western blotting were applied to recognize autophagy. The role of CARM1 in gastric cancer was investigated by CCK8, colony formation and flow cytometry assays in vitro and xenograft model in vivo. Immunoprecipitation assay was performed to illustrate the interaction of CARM1 and TFE3.Results: CARM1 was upregulated in clinical GC tissues and cell lines, and higher CARM1 expression predicted worse prognosis. CARM1 enhanced GC cell proliferation, facilitated G1-S transition and inhibited ER stress-induced apoptosis by regulating autophagy. Importantly, the treatment of CARM1 inhibitor rescued the tumor-promoting effects of CARM1 both in vitro and in vivo. Furthermore, we proved CARM1 heightened TFE3 nuclear translocation to induce autophagy via cytoplasmic AMPK-mTOR and nuclear CARM1-TFE3 signaling pathways.Conclusion: CARM1 promoted GC cell proliferation, accelerated G1-S transition and reduced ER stress-induced apoptosis by regulating autophagy. Mechanically, CARM1 triggered autophagy by facilitating TFE3 nuclear translocation via AMPK-mTOR and CARM1-TFE3 signaling pathways.

Pancreatic ductal adenocarcinoma (PDAC) has the highest fatality rate of any solid tumor, with a five-year survival rate of only 10% in the USA. PDAC is characterized by early metastasis. More than 50% of patients present with distant metastases at the time of diagnosis, and the majority of patients will develop metastasis within 4 years after tumor resection. Despite extensive studies, the molecular mechanisms underlying PDAC metastasis remain unclear. The polyoma enhancer activator protein (PEA3) subfamily was reported to play a vital role in the initiation and progression of multiple tumors. Herein, we found that ETS variant 4 (ETV4) was highly expressed in PDAC tissues and associated with poor survival. Univariate and multivariate analyses revealed that ETV4 expression was an independent prognostic factor for patient survival. Further experiments showed that ETV4 overexpression promoted PDAC invasion and metastasis both in vitro and in vivo. For the first time, we demonstrated that, mechanistically, ETV4 increased CXCR5 expression by directly binding to the CXCR5 promoter region. Knockdown of CXCR5 significantly reversed ETV4-mediated PDAC migration and invasion, while CXCR5 overexpression exerted the opposite effects. Intriguingly, we found that CXCL13, a specific ligand of CXCR5, increased ETV4 expression and promoted PDAC invasion and metastasis by activating the ERK1/2 pathway. ETV4 knockdown significantly abrogated the enhanced migratory and invasive abilities induced by the CXCL13/CXCR5 axis. In addition, a CXCR5 neutralizing antibody disrupted the CXCL13/ETV4/CXCR5 positive feedback loop and inhibited cell migration and invasion. Overall, in this study, we demonstrated that ETV4 plays a vital role in PDAC metastasis and defined a novel CXCL13/ETV4/CXCR5 positive feedback loop. Targeting this pathway has implications for potential therapeutic strategies for PDAC treatment.

Marine/maritime spatial planning (MSP) aims to address conflicts between different sea uses and conflicts between such uses and marine environments. However, how to evaluate, particularly quantitatively evaluate, an MSP scheme on its performance of achieving the above objectives is still an issue. In this paper, an MSP scheme evaluation framework focusing on sea use compatibility and the protection degree of key ecological areas is put forward. First, the intensity of every sea use is graded on a scale of 1–10 based on its demand on marine resources and impacts on marine environments, and key ecological areas are identified based on scientific criteria for ecologically or biologically significant marine areas of the Convention on Biological Diversity (CBD). Then, a set of formulas are designed to calculate the conflict value among sea uses. The protection degree in a sea area is calculated through buffer zone tools and overlap analysis in Geographic Information System (GIS). The proposed method is applied to a case study of Xiamen, China, by comparing its marine spatial plans of version 2007 and version 2013. The results show that the sea use intensity increases from 3.51 to 4.20 on average in the Western Sea of Xiamen. The key ecological area protection value decreases from 0.59 to 0.45, and the sea use conflicts value decreases from 0.28 to 0.20. The results demonstrate that MSP is successful in reducing sea use conflicts in version 2013 in the context of an increasing sea use intensity. However, the protection degree of key ecological areas needs to be strengthened. Further statistical analysis of the results provides more information for the cause analysis of the performance changes. This information would inform potential revisions of the current marine spatial plan and future sea use management. The proposed method provides a feasible approach to analyse the MSP scheme in a quantitative way.

DEAD-Box Helicase 3 X-Linked (DDX3X) is a member of the DEAD-box helicases that play a crucial role in RNA metabolism. Although DDX3X has been shown to contribute to tumorigenesis, the detailed mechanisms by which DDX3X functions in pancreatic ductal adenocarcinoma (PDAC) biogenesis remain poorly understood. The goal of the present study was to elucidate the molecular mechanisms by which DDX3X contributes to tumorigenesis in PDAC. Kaplan–Meier curves, the log-rank test, t test and Cox regression were used to analyze the relationship between DDX3X expression and the clinicopathological features of PDAC patients. DDX3X and p62 expression in human PDAC tissues was analyzed by immunohistochemistry. Monolayer scratch healing assays, cell migration assays and nude mouse lung metastasis models were used to evaluate the effect of DDX3X on metastasis in vitro and in vivo. Western blot analysis was used to assess the expression of proteins in the signaling pathway. We authenticated high DDX3X expression was associated with a poor prognosis in PDAC. The loss of DDX3X attenuated the migratory capacity of PDAC cells in vitro and in vivo. DDX3X was shown to facilitate epithelial-mesenchymal transition (EMT) and the phosphorylation of p65 and eIF2α. Moreover, DDX3X displayed oncogenic activity by promoting p62 accumulation. Our results demonstrated that DDX3X activates NF-κB and promotes metastasis by inducing EMT via p62.

Porcine parvovirus (PPV) is a major cause of reproductive failure in swine, and has caused huge losses throughout the world. The structural viral protein VP2, which is able to self-assemble into empty capsids, known as virus-like particles (VLPs), is crucial to induce PPV-specific neutralizing antibodies and protective immunity. In this study, twelve monoclonal antibodies (mAbs) against PPV were generated. The mAbs were characterized by indirect enzyme-linked immunosorbent assay (ELISA), western blotting (WB) and virus neutralization (VN) assay. Two mAbs were defined to be able to neutralize the standard PPV 7909 strain. Subsequently, peptide scanning was applied to identify linear epitopes. The peptide, 89ESGVAGQMV97 was defined as a precise linear epitope. Results from structural analysis showed that the epitope was exposed on the virion surface. Multiple sequence alignment analysis indicated that peptide 89ESGVAGQMV97 was not completely conserved, with a higher amino acid mutation rate at 91G, 92V and 93A position. Alanine-scanning mutagenesis further revealed that residues 89E, 90S, 91G, 92V and 94G were the core sites involved in antibody recognition. These findings may facilitate further understanding the function of the VP2 protein and development of diagnostic tools.

Four peptides were designed and synthesized according to the main FMDV type O vaccine strains in china. Then the synthesized peptides were conjugated to carrier protein. The antigenicity of the artificial antigen was identified by dot-blot assay. Based on the BSA-Pep antigen, a test strip was developed to evaluate the neutralizing antibody of serum samples from swine vaccinated with FMDV type O vaccine rapidly. The BSA-Pep used as a detector was labeled with colloidal gold. Staphylococcal protein A (SPA) and anti FMDV antibodies were blotted onto the nitrocellulose membrane as the test and control lines, respectively. The strip assay could be performed within 5 min, which did not require any special equipment or skills. Through testing sera against various strains of FMDV type O, the sensitivity of the strip was determined to be 95% (38/40). There were no cross reactions to other virus antibodies, and no cross reactions in different serotypes of FMDV, the test strip can be used to detect FMDV type O antibodies only. The strip results were consistent with those of the existing commercial ELISA kits. In conclusion, the new strip was an acceptable method for surveying FMDV type O antibody titers in pigs.

A gold nanoparticle strip was developed for rapidly evaluating FMDV type O antibody level and simultaneously discriminating FMDV vaccinated animals from infected animals. The strip was established depending on the colloidal gold nanoparticle labeling technique. Staphylococcal protein A colloidal gold nanoparticles were used as a probe. The epitope antigens of FMDV structural proteins and nonstructural proteins were dispensed on a nitrocellulose membrane as two test lines, respectively, and goat anti-pig antibody IgG was used as a control line. The assay was evaluated with FMDV immunized, infected sera and positive sera for another virus. The results showed the specificities of the T1 and T2 lines were 95.17% and 100% respectively. The sensitivity was in accordance with commercial ELISA kits. The coincidence rate of the new strip with 3ABC Mab-bELISA and LPB-ELISA was 95.5% and 93.13%, respectively. In summary, this experimental strip could provide a simple, inexpensive and rapid approach for onsite detection of FMDV type O antibody level and discrimination of FMDV vaccinated from infected animals without any expensive instrument.

Background The influenza A virus (IAV) is known for its high variability and poses a huge threat to the health of humans and animals. Pigs play a central role in the cross-species reassortment of IAV. Ectodomain of matrix protein 2 (M2e) is the most conserved protective antigen in IAV and can be used to develop nanovaccines through nanoparticles displaying to increase its immunogenicity. However, the high immunogenicity of nanoparticles can cause the risk of off-target immune response, and excess unwanted antibodies may interfere with the protective efficacy of M2e-specific antibodies. Therefore, it is necessary to select reasonable nanoparticles to make full use of antibodies against nanoparticles while increasing the level of M2e-specific antibodies. Porcine circovirus type 2 (PCV2) is the most susceptible virus in pigs and can promote IAV infection. It is meaningful to develop a vaccine that can simultaneously control swine influenza virus (SIV) and PCV2. Methods In the present study, M2e of different copy numbers were inserted into the capsid (Cap) protein of PCV2 and expressed in Escherichia coli to form self-assembled chimeric virus-like particles (VLPs) nanovaccine. BALB/c mice and pigs were immunized with these nanovaccines to explore optimal anti-IAV and anti-PCV2 immunity. Results Cap is capable of carrying at least 81 amino acid residues (three copies of M2e) at its C-terminal without impairing VLPs formation. Cap-3M2e VLPs induced the highest levels of M2e-specific immune responses, conferring protection against lethal challenge of IAVs from different species and induced specific immune responses consistent with PCV2 commercial vaccines in mice. In addition, Cap-3M2e VLPs induced high levels of M2e-specific antibodies and PCV2-specific neutralizing antibodies in pigs. Conclusion Cap-3M2e VLP is an economical and promising bivalent nanovaccine, which provides dual protection against IAV and PCV2.