Fourier Ptychographic Microscopy Reconstruction Method Based on Residual Local Mixture Network.

Fourier Ptychographic Microscopy (FPM) is a microscopy imaging technique based on optical principles. It employs Fourier optics to separate and combine different optical information from a sample. However, noise introduced during the imaging process often results in poor resolution of the reconstructed image. This article has designed an approach based on a residual local mixture network to improve the quality of Fourier ptychographic reconstruction images. By incorporating channel attention and spatial attention into the FPM reconstruction process, the network enhances the efficiency of the network reconstruction and reduces the reconstruction time. Additionally, the introduction of the Gaussian diffusion model further reduces coherent artifacts and improves image reconstruction quality. Comparative experimental results indicate that this network achieves better reconstruction quality, and outperforming existing methods in both subjective observation and objective quantitative evaluation.

Fourier Ptychographic Microscopic Reconstruction Method Based on Residual Hybrid Attention Network.

Fourier ptychographic microscopy (FPM) is a novel technique for computing microimaging that allows imaging of samples such as pathology sections. However, due to the influence of systematic errors and noise, the quality of reconstructed images using FPM is often poor, and the reconstruction efficiency is low. In this paper, a hybrid attention network that combines spatial attention mechanisms with channel attention mechanisms into FPM reconstruction is introduced. Spatial attention can extract fine spatial features and reduce redundant features while, combined with residual channel attention, it adaptively readjusts the hierarchical features to achieve the conversion of low-resolution complex amplitude images to high-resolution ones. The high-resolution images generated by this method can be applied to medical cell recognition, segmentation, classification, and other related studies, providing a better foundation for relevant research.

Inhibition of canine distemper virus replication by blocking pyrimidine nucleotide synthesis with A77 1726, the active metabolite of the anti-inflammatory drug leflunomide.

Canine distemper virus (CDV) is the aetiological agent that causes canine distemper (CD). Currently, no antiviral drugs have been approved for CD treatment. A77 1726 is the active metabolite of the anti-rheumatoid arthritis (RA) drug leflunomide. It inhibits the activity of Janus kinases (JAKs) and dihydroorotate dehydrogenase (DHO-DHase), a rate-limiting enzyme in de novo pyrimidine nucleotide synthesis. A77 1726 also inhibits the activity of p70 S6 kinase (S6K1), a serine/threonine kinase that phosphorylates and activates carbamoyl-phosphate synthetase (CAD), a second rate-limiting enzyme in the de novo pathway of pyrimidine nucleotide synthesis. Our present study focuses on the ability of A77 1726 to inhibit CDV replication and its underlying mechanisms. Here we report that A77 1726 decreased the levels of the N and M proteins of CDV and lowered the virus titres in the conditioned media of CDV-infected Vero cells. CDV replication was not inhibited by Ruxolitinib (Rux), a JAK-specific inhibitor, but by brequinar sodium (BQR), a DHO-DHase-specific inhibitor, and PF-4708671, an S6K1-specific inhibitor. Addition of exogenous uridine, which restores intracellular pyrimidine nucleotide levels, blocked the antiviral activity of A77 1726, BQR and PF-4708671. A77 1726 and PF-4708671 inhibited the activity of S6K1 in CDV-infected Vero cells, as evidenced by the decreased levels of CAD and S6 phosphorylation. S6K1 knockdown suppressed CDV replication and enhanced the antiviral activity of A77 1726. These observations collectively suggest that the antiviral activity of A77 1726 against CDV is mediated by targeting pyrimidine nucleotide synthesis via inhibiting DHO-DHase activity and S6K1-mediated CAD activation.

Mass spectrometry-based proteomic analysis of potential infectious bursal disease virus VP3-interacting proteins in chicken embryo fibroblasts cells.

The structural protein VP3 of infectious bursal disease virus (IBDV) plays a critical role in viral assembly, replication, immune escape, and anti-apoptosis. Interaction between VP3 and host protein factors can affect stages in the viral replication cycle. In this study, 137 host proteins interacting with VP3 protein were screened through liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based proteomics approach. The functions and relevance of the proteins were obtained through bioinformatics analysis. Most VP3-interacting proteins were linked to binding, catalytic activity, and structural molecular activity, and performed functions in cell parts and cells. Biological functions of VP3-interacting proteins were mainly relevant to "Cytoskeleton", "Translation", and "Signal transduction mechanisms", involving ribosomes, "Tight junction", regulation of actin cytoskeleton, and other pathways. Six potential VP3-interacting proteins in host cells were knocked down, and vimentin, myosin-9, and annexin A2 were found to be related to IBDV replication. This study would help explore regulatory pathways and cellular mechanisms in IBDV-infected cells, and also provided clues for the in-depth study of VP3 biological functions and IBDV replication or pathogenesis.

Comparison of the virulence of three H3N2 canine influenza virus isolates from Korea and China in mouse and Guinea pig models.

BACKGROUND: Avian-origin H3N2 canine influenza virus (CIV) has been the most common subtype in Korea and China since 2007. Here, we compared the pathogenicity and transmissibility of three H3N2 CIV strains [Chinese CIV (JS/10), Korean CIV (KR/07), and Korean recombinant CIV between the classic H3N2 CIV and the pandemic H1N1 virus (MV/12)] in BALB/c mouse and guinea pig models. The pandemic H1N1 (CA/09) strain served as the control. RESULTS: BALB/c mice infected with H1N1 had high mortality and obvious body weight loss, whereas no overt disease symptoms were observed in mice inoculated with H3N2 CIV strains. The viral titers were higher in the group MV/12 than those in groups JS/10 and KR/07, while the mice infected with JS/10 showed higher viral titers in all tissues (except for the lung) than the mice infected with KR/07. The data obtained in guinea pigs also demonstrated that group MV/12 presented the highest loads in most of the tissues, followed by group JS/10 and KR/07. Also, direct contact transmissions of all the three CIV strains could be observed in guinea pigs, and for the inoculated and the contact groups, the viral titer of group MV/12 and KR/07 was higher than that of group JS/10 in nasal swabs. These findings indicated that the matrix (M) gene obtained from the pandemic H1N1 may enhance viral replication of classic H3N2 CIV; JS/10 has stronger viral replication ability in tissues as compared to KR/07, whereas KR/07 infected guinea pigs have more viral shedding than JS/10 infected guinea pigs. CONCLUSIONS: There exists a discrepancy in pathobiology among CIV isolates. Reverse genetics regarding the genomes of CIV isolates will be helpful to further explain the virus characteristics.

Phylogenetic analysis of canine distemper virus in domestic dogs in Nanjing, China.

Canine distemper virus (CDV) infects a broad range of carnivores, including wild and domestic Canidae. The hemagglutinin gene, which encodes the attachment protein that determines viral tropism, has been widely used to determine the relationship between CDV strains of different lineages circulating worldwide. We determined the full-length H gene sequences of seven CDV field strains detected in domestic dogs in Nanjing, China. A phylogenetic analysis of the H gene sequences of CDV strains from different geographic regions and vaccine strains was performed. Four of the seven CDV strains were grouped in the same cluster of the Asia-1 lineage to which the vast majority of Chinese CDV strains belong, whereas the other three were clustered within the Asia-4 lineage, which has never been detected in China. This represents the first record of detection of strains of the Asia-4 lineage in China since this lineage was reported in Thailand in 2013.

Development and characterization of neutralizing monoclonal antibodies against canine distemper virus hemagglutinin protein.

Canine distemper virus (CDV) causes a serious multisystemic disease in dogs and other carnivora. Hemagglutinin (H) protein-specific antibodies are mainly responsible for protective immunity against CDV infection. In the present study, six neutralizing MAbs to the H protein of CDV were newly obtained and characterized by immunizing BALB/c mice with a recent Chinese field isolate. Competitive binding inhibition assay revealed that they recognized four distinct antigenic regions of the H protein. Immunofluorescence assay and western blotting showed that all MAbs recognize the conformational rather than the linear epitopes of the H protein. Furthermore, in immunofluorescence and virus neutralization assays, two of the MAbs were found to react only with the recent Chinese field isolate and not with older CDV strains, including vaccine strain Onderstepoort, indicating there are neutralization-related antigenic variations between the recent Chinese field isolate and the older CDV strains examined in this study. The newly established MAbs are useful for differentiating the expanding CDV strains and could be used in immunotherapy and immunodiagnosis against infection with CDV.

Development of real-time PCR assay for detection of porcine circovirus-like virus P1 in domestic pigs in China.

BACKGROUND: The porcine circovirus-like agent P1 is a newly discovered DNA virus with a single-stranded circular genome that is highly homologous to that of porcine circovirus type 2. P1 infection can cause symptoms resembling postweaning multisystemic wasting syndrome. This study aims to develop a rapid, sensitive and specific method to detect P1. RESULTS: A pair of primers was designed and used to amplify a 119 bp DNA fragment to generate a recombinant plasmid which was served as the standard. A SYBR I qPCR protocol was established using the P1 recombinant plasmid standard and the sensitivity, specificity and stability of this method was analyzed. The results demonstrate a strong correlation with P1 recombinant plasmid titers when virus DNA copy numbers fall in between 10(0) ~ 10(9) copies/µL. This method doesn't detect pseudo rabies, porcine parvovirus or porcine reproductive and respiratory syndrome virus; moreover it can distinguish porcine circovirus type 2 from P1 by melting temperature analysis. Coefficient of variation for each batch of reaction is less than 5%. The serum virus titers of P1 positive in this study were measured by this protocol to be 10(3) to 10(7) copies/mL. CONCLUSIONS: The established qPCR is sensitive, specific, and reliable, which could be a useful tool when applied to quantification of P1 in a variety of samples from infected pigs.

[Reversal Effect of NVP-BEZ235 on Doxorubicin-Resistance in Burkitt Lymphoma RAJI Cell Line].

OBJECTIVE: To study the reversal effect of NVP-BEZ235 on doxorubicin resistance in Burkitt lymphoma RAJI cell line. METHODS: The doxorubicin-resistant cell line was induced by treating RAJI cells with a concentration gradient of doxorubicin. The levels of Pgp, p-AKT, and p-mTOR in cells were detected by Western blot. Cell viability was detected by MTT assay. IC50 was computed by SPSS. RESULTS: The doxorubicin-resistant Burkitt lymphoma cell line, RAJI/DOX, was established successfully. The expression of Pgp and the phosphorylation levels of AKT and mTOR in RAJI/DOX cell line were both higher than those in RAJI cell line. NVP-BEZ235 downregulated the phosphorylation levels of AKT and mTOR in RAJI/DOX cell line. NVP-BEZ235 inhibited the proliferation of RAJI/DOX cell line, and the effect was obvious when it was cooperated with doxorubicin. CONCLUSION: The constitutive activation of PI3K/AKT/mTOR pathway of RAJI/DOX cell line was more serious than RAJI cell line. NVP-BEZ235 reversed doxorubicin resistance of RAJI/DOX cell line by inhibiting the PI3K/AKT/mTOR signal pathway.

Influence of minor displacements in loops of the porcine parvovirus VP2 capsid on virus-like particles assembly and the induction of antibody responses.

An antigen-delivery system based on hybrid virus-like particles (VLPs) formed by the self-assembly of the capsid VP2 protein of porcine parvovirus (PPV) and expressing foreign peptides offers an alternative method for vaccination. In this study, the three-dimensional structure of the PPV capsid protein and surface loops deletion mutants were analyzed to define essential domains in PPV VP2 for the assembly of VLPs. Electron microscopic analysis and SDS-PAGE analysis confirmed the presence of abundant VLPs in a loop2 deletion mutant of expected size and appropriate morphology. Loop4 and loop2-loop4 deletion mutants, however, resulted in a lower number of particles and the morphology of the particles was not well preserved. Furthermore, the green fluorescent protein (gfp) gene was used as a model. GFP was observed at the same level in displacements mutants. However, GFP displacement mutants in loop2 construct allowed better adaptation for the fusion GFP to be further displayed on the surface of the capsid-like structure. Immunogenicity study showed that there is no obvious difference in mice inoculated with rAd-VP2(Δloop2), rAd-VP2(Δloop4), rAd-VP2(Δloop2-Δloop4), and PPV inactivated vaccine. The results suggested the possibility of inserting simultaneously B and T cell epitopes in the surface loop2 and the N-terminus. The combination of different types of epitopes (B, CD4+, and CD8+) in different positions of the PPV particles opens the way to the development of highly efficient vaccines, able to stimulate at the same time the different branches of the immune system.

Molecular epidemiology and genetic evolution of canine parvovirus in East China, during 2018-2020.

Canine parvovirus type 2 (CPV-2) emerged in the late 1970s, which caused high rates of morbidity and mortality in dogs. In last decade, five genetic variants (CPV-2a, CPV-2b, CPV-2c, New CPV-2a, and New CPV-2b) were frequently reported in the dog population, and replaced the original CPV-2, rising widespread concerns. However, little is known about their recent genetic diversity and evolution. The aim of this study was to analyze the characteristics of the CPV-2 strains collected in East China from 2018 to 2020. The 57 CPV-2 strains were isolated from rectal swab samples (n=140). They belong to three different genotypes, based on VP2 protein amino acid sequence. The results revealed a high prevalence of CPV-2c (77.19%) compared to the New CPV-2a (5.26%) and New CPV-2b (17.54%) strains. Further analysis showed that nucleotide homology of the VP2 gene among the 57 CPV strains was 98.9%~100%, and the homology with 24 reference strains from different countries and regions was 98.1%~100%. The phylogenetic tree of VP2 gene sequence showed that 44 CPV-2c strains were distantly related to CPV-2, CPV-2a, CPV-2b, New CPV-2a, New CPV-2b and European/American CPV-2c strains, and were closely related to Asian CPV-2c strains. The results showed that these Asian CPV-2c strains had become the dominant strain, which renewed the knowledge of CPV-2 molecular epidemiology in East China.

Effect of Heat Treatment Temperature on Martensitic Transformation and Superelasticity of the Ti49Ni51 Shape Memory Alloy.

The martensitic transformation and superelasticity of Ti49Ni51 shape memory alloy heat-treatment at different temperatures were investigated. The experimental results show that the microstructures of as-cast and heat-treated (723 K) Ni-rich Ti49Ni51 samples prepared by rapidly-solidified technology are composed of B2 TiNi phase, and Ti3Ni4 and Ti2Ni phases; the microstructures of heat-treated Ti49Ni51 samples at 773 and 823 K are composed of B2 TiNi phase, and of B2 TiNi and Ti2Ni phases, respectively. The martensitic transformation of as-cast Ti49Ni51 alloy is three-stage, A→R→M1 and R→M2 transformation during cooling, and two-stage, M→R→A transformation during heating. The transformations of the heat-treated Ti49Ni51 samples at 723 and 823 K are the A↔R↔M/A↔M transformation during cooling/heating, respectively. For the heat-treated alloy at 773 K, the transformations are the A→R/M→R→A during cooling/heating, respectively. For the heat-treated alloy at 773 K, only a small thermal hysteresis is suitable for sensor devices. The stable σmax values of 723 and 773 K heat-treated samples with a large Wd value exhibit high safety in application. The 773 and 823 K heat-treated samples have large stable strain-energy densities, and are a good superelastic alloy. The experimental data obtained provide a valuable reference for the industrial application of rapidly-solidified casting and heat-treated Ti49Ni51 alloy.

Effect of Fe Addition on Microstructure and Mechanical Properties of As-cast Ti49Ni51 Alloy.

Effect of Fe addition on microstructure and mechanical properties of as-cast Ti49Ni51 alloy were investigated. The experimental results shows the microstructures of Ti48.5Ni51Fe0.5 and Ti48Ni51Fe1 alloys are mainly composed of TiNi matrix phase (body-centered cubic, BCC), Ti3Ni4 and Ni2.67Ti1.33 phases; the microstructure of Ti47Ni51Fe2 alloy is mainly composed of BCC TiNi, Ti3Ni4, Ni2.67Ti1.33, and Ni3Ti phases; the microstructure of the Ti45Ni51Fe4 alloy is mainly composed of TiNi, Ti3Ni4 and Ni3Ti phases. The Ni3Ti nanocrystalline precipitates at the adjacent position of Ni2.67Ti1.33 phase. The Ti48.5Ni51Fe0.5 and Ti48Ni51Fe1 alloys have high yield strength and fracture strength, and can be as the engineering materials with excellent mechanical properties. In addition, the Ti48.5Ni51Fe0.5 alloy with the low elastic modulus and large elastic energy is also a good biomedical alloy of hard tissue implants. The fracture mechanism of the four alloys is mainly cleavage fracture or quasi-cleavage fracture, supplemented by ductile fracture. The experimental data obtained provide the valuable references in application of as-cast alloys and heat-treated samples in the future.

A genotype VII Newcastle disease virus-like particles confer full protection with reduced virus load and decreased virus shedding.

Newcastle disease (ND) is one of the most severe avian infectious disease inflicting a great loss on poultry industry worldwide. The control of ND relies on proper vaccination strategies. The vaccine strains of Newcastle disease virus (NDV) mainly belong to genotype I, II or III, which cannot fully prohibit virus shedding against the prevalent genotype VII virulent strain attack. To develop a safe, genotype matched vaccine candidate, we employed a bac-to-bac expression system and constructed a genotype VII NDV strain based virus-like particles (NDV VLPs). It was constructed with NDV M protein as the skeleton, and protective antigen F and HN proteins displayed on the surface. The NDV VLPs exhibited a similar appearance to the live NDV particles, but with denser F and HN proteins displayed on the surface. The immunization assay indicated that NDV VLPs stimulated a longer protection period, less tissue virus loading and shorter virus shedding period than the commercialized LaSota-formulated vaccine when challenged with genotype VII NDV strain. These results proposed the potential role of NDV VLPs as an alternative to current live genotype unmatched vaccine for the control and eliminate NDV in the avian flocks.

Determination of the mimic epitope of the M-like protein adhesin in swine Streptococcus equi subsp. zooepidemicus.

BACKGROUND: The M-like protein, also known as SzP, is expressed on the surface of Streptococcus equi subsp. zooepidemicus (S. zooepidemicus). Previous studies demonstrated that SzP is similar to M protein of group A Streptococcus in the structure and characteristics of antiphagocytosis. The M protein is an adhesin that can bind to the host cells, however it is not known whether the SzP of S. zooepidemicus also functions as an adhesin. We conducted an investigation to determine SzP as an adhesin, and one SzP epitope was identified to be responsible for mediating binding to HEp-2 cells. METHODS: The gene encoding SzP was expressed in E. coli, and the purified recombinant SzP (rSzP) was recognized by rabbit anti-S. zooepidemicus antibodies using immunoblot. Furthermore, the adherence of S. zooepidemicus to HEp-2 cells was inhibited by anti-rSzP antibodies in a dose-dependent manner. We employed a random 12-peptide phage display library for screening of immunodominant mimics of the SzP, which were recognized by an anti-SzP specific monoclonal antibody (mAb 2C8). Initial positive phage clones were identified by ELISA, followed by assays to determine the adherence-inhibiting ability of the peptide. RESULTS: Ten out of fourteen selected positive clones showed high reactivity that effectively inhibited the binding of mAb 2C8 to rSzP. The motif XSLSRX was highly conserved among six of the ten clones. CONCLUSION: Collectively, our findings suggest that the motif XSLSRX may represent an immunodominant mimic epitope of the SzP of S. zooepidemicus strain ATCC 35246, and that the same epitope may be used to mediate SzP binding to HEp-2 cells.

Costate prediction based optimal control for non-linear hybrid systems.

This paper is derived for solving a non-linear discrete-continuous systems optimal control problem by iterating on a sequence of simplified problems in discrete form. A mixed approach with a discrete cost function and continuous state variable system description is used as the basis of the design, and it is shown how the global problem can be decomposed into local subsystem problems and a coordinator within a hierarchical framework. The correct optimal solution to a real system in which model-reality difference exists can be obtained from the system model by interconnected costate prediction iterative solution. The algorithm efficiency and convergence properties are demonstrated by simulation study.

gga-miR-142-5p attenuates IRF7 signaling and promotes replication of IBDV by directly targeting the chMDA5's 3' untranslated region.

Chicken melanoma differentiation-associated gene 5 (chMDA5) is a key pattern recognition receptor (PRR) that recognizes RNA viral infections and initiates an antiviral innate immune response in chickens. MicroRNAs (miRNAs) are involved in the regulation of chMDA5 to sense RNA virus infection, but how it exerts antiviral activity against infectious bursal disease virus (IBDV) infection and regulates chMDA5 in chicken cells is unclear. Thus, we measured the expression of chMDA5 in IBDV-infected DT40 cells and found it significantly increased. Overexpression of chMDA5 activated the IFN-ß and Mx promoters via IRF7-dependent pathways and inhibited replication of IBDV in DT40 cells. The opposite effect occurred after chMDA5 knockdown using siRNA. Also, gga-miR-142-5p regulated chMDA5 according to bioinformatic analysis and data from a dual-luciferase reporter system. Overexpression of gga-miR-142-5p reduced the expression of the chMDA5 protein, promoting IBDV replication, and decreased the activity of the IFN-ß and Mx promoters via an IRF7-dependent pathway; however, it had no effect on the NF-κB-dependent pathway in DT40 cells. Thus, gga-miR-142-5p is a negative regulator of chMDA5 and promotes IBDV replication in DT40 cells through an IRF7-dependent pathway.

[Expression and immunogenic analysis for the tandem-arranged multiple mimic epitope gene of infectious bursal disease virus].

Five mimic epitopes of Infectious bursal disease virus (IBDV) have been identified from a 12-mer phage-displayed peptide library by 5 monoclonal antibodies. Based on the sequences of the five epitopes, multiple epitope gene 5epis was constructed by the five epitopes being tandemly arranged and linked with 4-peptide GGGS. The expression plasmid pET-5epis was constructed and successfully expressed in E. coli. The resultant protein of 5epis was called r5EPIS. The results from SDS-PAGE analysis showed that the proportion of r5EPIS was 15% of the total bacterial proteins and the molecular weight of r5EPIS was 10kDa. By use of parallel immunoblotting test with corresponding monoclonal and polyclonal antibodies, the immunological specificity and reactivity of r5EPIS against IBDV have been verified. Rabbits were subcutaneously injected with r5EPIS (400 micro g per injection), twice with 7 days interval. The titers of the IBDV-specific antibody measured by indirect ELISA were up to 1:4000 at the 7th day after first immunization and 1:256000 at the 14th day after the second immunization. To determine the protective ability of r5EPIS to the challenge of IBDV, chickens were injected intramuscularly with r5EPIS in adjuvant twice with 7 days interval (501g per injection) and the resultant antibody titer was up to 1:12800 at the 7'h day after the second immunonization. After challenge with 200ELD50 of virulent IBDV GX8/99 strain, all the chicken in r5EPIS-immunized group were survived in contrast to the mortality of 86.7%(13/15) in adjuvant control group, suggesting that r5EPIS had a potent ability to generate protective immune response and it implied that the constructed gene 5epis is a prospective candidate for the development of epitope-based IBD vaccine.

Development of CDV-specific monoclonal antibodies for differentiation of variable epitopes of nucleocapsid protein.

The highly contagious canine distemper viruses (CDVs) are still a major threat to a wide range of natural susceptible hosts. The nucleocapsid (N) protein plays various roles in the virus-induced immune response. But precise mapping of epitopes and antigenic variations in N protein of CDV are still scant. In this study, two monoclonal antibodies (MAbs), designated as F8N and G3N, against the N protein of CDV were generated and characterized. The epitopes recognized by the two MAbs were mapped by truncated N protein fragments expressed in E.coli based on western blotting. The 470ESRYDTQ476 and 385GITKEEAQL393 were identified as the minimal linear epitopes recognized by F8N and G3N, respectively. The amino acid residues of the epitope (385-393aa) were highly conserved in a variety of CDV strains from the databases as well as five CDV strains in this study, indicating that MAb G3N can detect various CDV strains. However, MAb F8N was found not to react with an older CDV 851 strain of the five CDV strains due to both of two amino substitution (S471P and Y473H) in the epitope, whereas either single mutant S471P or Y473H did not eliminate the binding of F8N. Further, the variable epitopes existed in the N protein of six CDV strains resembling CDV3 in phylogenic tree by alignment with sequences from the databases. This is the first record of a precise epitope affecting antigenity of N protein of CDV. These results may facilitate future investigations into the function of NP of CDV and diagnostic methods for CDV infection.

gga-miR-2127 downregulates the translation of chicken p53 and attenuates chp53-mediated innate immune response against IBDV infection.

Infectious bursal disease (IBD) is characterized by the immune suppression of infected birds. The molecular mechanism by which IBD virus (IBDV) suppresses the host immune system remains to be elucidated. The tumor suppressor protein p53 can inhibit the replication of various viruses, but its effect on IBDV remains unknown. This study established an in vitro infection model based on DF-1 cells (chicken embryo fibroblast cell line) to investigate the antiviral effects of chicken p53 (chp53) on IBDV infection. The expression level and activity of chp53 remarkably increased in IBDV-infected DF-1 cells. The overexpression of chp53 inhibited IBDV replication and upregulated the expression of multiple chicken antiviral innate immunity genes (IPS-1, IRF3, PKR, OAS, and Mx), whereas the suppression of chp53 led to the opposite effect. This result indicates that chp53 activates the antiviral innate immune response of chickens to IBDV infection. Bioinformatics analysis and dual-luciferase reporter assay showed that gga-miR-2127 targeted the 3'UTR of chp53. qRT-PCR and western blot revealed that gga-miR-2127 overexpression in DF-1 cells not only downregulated the expression levels of chp53 and of the antiviral innate immunity genes in chickens but also promoted IBDV replication. Our results suggest that gga-miR-2127 downregulates chp53 mRNA translation by targeting its 3'UTR and attenuates chp53-mediated antiviral innate immune response against IBDV.