To explore the interaction between ASFV capsid protein M1249L and host from the host cellular perspective,M1249L was selected for constructing the bait plasmid(pGBKT7-M1249L)to screen the bone marrow-derived macrophages(BMDMs)cDNA library.After again co-transform and sequence alignment,20 candidate interacting host proteins were screened,such as IL-1β,CTSB and DNAJA3.And then,co-immunoprecipitation assay was performed to verify the interaction be-tween M1249L and host proteins.GO ontology(GO)and KEGG pathway enrichment analyses re-vealed that biological regulation,cellular communication and response to stimulus and others were enriched in biological processes.And these host proteins could share some pathways,including toll-like receptor signaling pathway and Nod-like receptor signaling pathway.Therefore,the results provides the theoretical basis for further research on the mechanism of ASFV M1249L in viral in-fection and immune regulation.

This study constructed a porcine reproductive and respiratory syndrome virus(PRRSV)NADC30-like strain GP3 recombinant adenovirus vector vaccine through in vitro homologous re-combination to explore its immunological efficacy evaluation at the mouse level.Using type 5 ade-novirus as a vector,a recombinant adenovirus expressing PRRSV GP3 protein was prepared and i-dentified in vitro by fluorescence observation,PCR,and Western blot analysis.Immunize mice with recombinant adenovirus and detect humoral and cellular immune responses induced by recombi-nant adenovirus using indirect ELISA and ELISpot methods.The recombinant adenovirus rAdGP3 was identified by enzyme digestion,PCR,fluorescence and Western blot,indicating that the recom-binant adenovirus rAdGP3 was successfully constructed and packaged.After immunizing mice,spe-cific antibodies and neutralizing antibodies were produced,indicating that the recombinant adenovi-rus could elicit strong humoral immunity.ELISpot and lymphocyte proliferation assays showed that the recombinant adenovirus vaccine could stimulate the secretion of IFN-γ-specific T lymphocytes and induce the proliferation of lymphocytes,indicating that the recombinant adenovi-rus could enhance the level of cellular immune response.In this study,rAdGP3 recombinant adeno-virus was successfully constructed and had good immunogenicity at the mouse level,which provid-ed a reference for the development of novel PRRSV vaccines.

The receptor-binding region(RBD)of the spike protein(S)on the surface of porcine epi-demic diarrhea virus(PEDV)is a critical structural domain mediating viral invasion of host cells and serves as a key target for inducing neutralizing antibodies.In order to prepare antibodies that can be used to study the biological function of PEDV RBD and develop novel diagnostic and thera-peutic methods,recombinant RBD protein expressed in Sf9 insect cells was utilized as an immuno-gen to immunize BALB/c mice.Monoclonal antibodies(mAbs)were generated via hybridoma tech-nology,and positive hybridoma clones were screened using indirect ELISA.The reactivity of the mAbs was subsequently characterized.The results of ELISA,Western blot,and indirect immuno-fluorescence assay(IFA)showed that three monoclonal antibodies screened(3E5,4F9 and 5A5)had good reactivity with the virus and RBD protein.Antibody subtype results showed that 3E5 and 4F9 were of IgG1 subtypes and 5A5 was of IgM subtype.Neutralization assay further revealed that 3E5 monoclonal antibody had viral neutralizing activity.In this study,three monoclonal antibodies against PEDV RBD proteins were successfully prepared,providing the basis for the study of the bi-ological function of RBD proteins,PEDV serologic detection and vaccine development.

A quadruplex RT-qPCR method was developed for rapid identification and diagnosis of transmissible gastroenteritis virus(TGEV)of swine,porcine epidemic diarrhea virus(PEDV),porcine deltacorona virus(PDCoV),and porcine rotavirus type A(PoRVA).The full-length sequences of PEDV(77 strains),TGEV(63 strains),PDCoV(17 strains)that are prevalent in China,as well as the 85 VP6 gene sequences of PoRVA,were downloaded from the NCBI database for homology analysis.Based on the relatively conserved sequences,the corresponding primers and probes for each virus were designed and used to establish the quadruplex RT-qPCR method.After optimization of the probes and the reaction conditions,the specificity,sensitivity,and repeatability were determined.Using the established method,109 clinical samples of diarrhea were tested and further compared with the results by standard method.The results showed that the quadruplex RT-qPCR method established in this experiment has good amplification effect,with the C,value linearly correlated with the copies of templates(R2＞0.99).Specificity assay demonstrated that the quadruplex RT-qPCR method can identify TGEV,PEDV,PDCoV,PRoVA strains,and do not de-tect African swine fever virus(ASFV),porcine circovirus type 2(PCV2),porcine reproductive and respiratory syndrome virus(PRRSV),classical swine fever virus(CSFV),pseudorabies virus(PRV)and other epidemic viruses.Sensitivity assay showed that the detection limits for TGEV,PEDV,PDCoV and PoRVA were 10,20,20 and 50 copies/μL,respectively.The method exhibits excellent reproducibility,with coefficients of variation(Cv)for both intra-and inter-assay repli-cates being less than 1％.Detection of 109 samples of diarrhea by this method yielded the coinci-dence rate of 100％with the industry standard,indicating high practical applicability.The devel-oped method possesses the advantages of strong strain compatibility,high sensitivity,strong speci-ficity,good repeatability and stability.It is suitable for virus diagnosis and large-scale clinical sam-ple testing,providing technical support for disease prevention and control as well as epidemiologi-cal investigation.

This study aims to establish an efficient protoplast-mediated genetic transformation sys-tem for Pochonia chlamydosporia(P.chlamydosporia)to facilitate gene transformation,genetic modification,and subsequent biological function research.Through orthogonal testing,the study systematically optimized key factors influencing electroporation,including voltage,osmotic stabi-lizer,pulse time,nucleic acid concentration,and protoplast concentration.The results showed that the optimal electroporation conditions were:voltage of 250 V,osmotic stabilizer as 0.6 mol/L su-crose solution,pulse time of 10 ms,plasmid concentration of 1％,and protoplast concentration of 1×107 protoplasts/mL,yielding a transformation efficiency of 0.4 × 103 CFU/pg.The interaction analysis revealed that the five factors affected transformation efficiency in the following order:plasmid concentration＞protoplast concentration＞pulse time＞osmotic stabilizer type＞voltage.Based on the positive transformants,the study further evaluated their colony morphology,growth rate,conidial yield,mycelial dry weight,and the ability to infect the eggs of three types of animal gastrointestinal nematodes.The results indicated that the electroporation process did not signifi-cantly affect the biological functions of P.chlamydosporia.The transformants successfully ex-pressed enhanced green fluorescent protein(EGFP),and PCR analysis confirmed the successful in-tegration of the thiostrepton resistance gene.In conclusion,this study successfully established a protoplast-based electroporation-mediated genetic transformation system for P.chlamydosporia,providing a valuable foundation for further research into the mechanism of egg parasitism and the underlying genes involved in its biocontrol activity.

In order to understand the genetic variation and whole genome characteristics of goose as-trovirus(GoAstV)in Jiangxi Province,a strain of GoAstV was successfully isolated from a typical gosling gout case sample and the whole genome sequencing and genetic characteristics of the isola-ted strain were analyzed.The results showed that the JXNC1 strain could be stably passaged on LMH cells and could cause mild cytopathic effects in LMH cells.Sequencing and analysis showed that the full-length genome of the strain was 7 173 bp,and its genetic relationship was the closest to the GZ2301(PP966939)reference strain,belonging to the GoAstV-Ⅱ genotype.The complete genome of JXNC1 strain shared 98.1％-98.8％nucleotide similarity with 22 GoAstV-Ⅱ reference strains,and the amino acid similarity of ORF2 gene was 97.6％-99.6％.At the same time,the analysis results showed that the mutation of the strain mainly occurred in the ORF2 gene,and there were 13 amino acid site mutations,of which T630I was a unique mutation.Animal regression experiments showed that the inoculation of JXNC1 strain could cause urate deposition in the or-gans of goslings,congestion and dilatation of hepatic sinusoids,and small focal necrosis of some hepatocytes.Renal tissue tubular dilatation,renal interstitial connective tissue hyperplasia.The re-sults of this study laid a foundation for accurate prevention and control of the disease.

The purpose of this study was to prepare high affinity monoclonal antibodies(mAbs)a-gainst bovine viral diarrhea virus(BVDV)and establish a double antibody sandwich ELISA detec-tion method.BVDV was purified by differential ultracentrifugation and used to immunize BALB/c mice.Hybridoma cells were prepared by fusing spleen cells from the immunized mice with SP2/0 cells.Positive cells were screened by indirect ELISA.A double-antibody sandwich ELISA method for detecting BVDV was developed using monoclonal antibody 4D11 as the capture antibody and HRP-labeled monoclonal antibody 3F3 as the detection antibody.The results of the ELISA and the determination of the variable region gene sequence of monoclonal antibodies indicated that the two monoclonal antibodies recognize different antigenic epitopes.Specificity tests showed that two monoclonal antibodies specifically recognize BVDV and did not cross-react with other bovine viru-ses associated with diarrhea.Indirect immunofluorescence assay and Western blot assay demonstra-ted that both mAbs exhibited strong reactivity with BVDV.The double antibody sandwich ELISA detection method established in this study had good specificity.The sensitivity test revealed that the method could detect a minimum virus amount of 3.1 × 104 TCID50.The reproducibility test showed that the inter-batch coefficient of variation(Cv)was between 2.47％and 7.44％,and the intra-batch Cv was between 1.71％and 9.89％,indicating good reproducibility.The establishment of this method provides an effective technical tool for the rapid diagnosis and prevention and con-trol of BVDV.

To understand the current epidemiological status and biological characteristics of avian paramyxoviruses(APMV)in wild birds in China,a total of 1 384 fecal samples of wild birds were collected in eight provinces(autonomous regions),including Ningxia,in 2023,to detect avian pa-ramyxovirus infections by viral isolation and RT-PCR.Positive samples were subjected to F gene sequence amplification and genetic evolutionary analyses.The results showed that 10 strains of APMV were isolated and identified from 1 384 wild bird feces samples with a positive rate of 0.72％.Out of the 10 strains,4 strains were APMV-1,which was in the same branch to the Ameri-can goose APMV-1 strain and had the homology ranging from 93％to 97.3％.Three strains of APMV-4 were in the same branch with the Russian duck APMV-4 strain and the Russian pintail APMV-4 strain,with homology ranging from 99.1％to 99.5％.Three strains were APMV-6,they were in the same branch with the Russian ruddy bladdered duck APMV-6 strain,with homology ranging from 98.7％to 99.20％.The intracerebral inoculatable pathogenicity index(ICPI)of the four strains for 1-day-old chicks ranged from 0 to 0.48,which was low in pathogenicity for chick-ens.The above results enriches the epidemiological information and the biological characteristics of avian paramyxovirus in wild birds in China,which provides a reference for the early warning,scien-tific prevention and control of this disease.

Glaesserella parasuis is the causative agent of Gl?sser's disease in pigs.However,the pathogenic mechanisms underlying its virulence is not yet fully understood.The RuvB protein,a member of the AAA+superfamily,is implicated in various cellular processes,yet its specific role in the virulence of Glaesserella parasuis has not been fully characterized.In this study,we con-structed a RuvB gene deletion mutant,designated ΔRuvB,using the serotype 13 Glaesserella pa-rasuis strain ZJ1208 and a suicide plasmid-mediated natural transformation approach.To elucidate the functional role of the RuvB gene,we comprehensively evaluated the biological characteristics of the ΔRuvB strain through a series of assays,including growth kinetics,colony morphology,bac-terial staining,transmission electron microscopy(TEM),osmotic stress tolerance,high-tempera-ture tolerance,heat shock resistance,UV resistance,capsular polysaccharide quantification,serum bactericidal assays,and murine virulence experiments.Our findings revealed that the growth rate of ΔRuvB showed no significant difference compared to the parental strain.TEM revealed a notable increase in bacterial cell length;however,the number of outer membrane vesicles(OMVs)on the surface of ΔRuvB did not significantly increase.Notably,the ΔRuvB strain displayed a significant reduction in capsular polysaccharide production and serum resistance,as well as diminished toler-ance to UV radiation and high temperatures.Significant alterations were observed in its resistance to osmotic stress or oxidative stress.In the mouse toxicity challenge experiment,in com-parison with the parental strain ZJ1208,the mortality rate dropped by 20 percentage points,suggesting that the virulence of ΔRuvB has been weakened to some extent.Collectively,these results underscore the critical role of the RuvB gene in enhancing the environmental adaptability of Glaesserella parasuis.

Acute pancreatitis(AP)is a common and severe digestive disease in dogs,characterized by a high recurrence rate and complications that significantly impact canine health.This study in-vestigates the mechanism by which adipose-derived stem cells(ADSCs)regulate the CHOP/Bcl-2 pathway to mitigate acute pancreatic injury in dogs.Twenty Beagle dogs were randomly divided in-to four groups:a Sham group,an AP model group,an ADSCs treatment group,and a conditioned medium(CM)treatment group.The AP model was established by injecting a mixed solution of trypsin and sodium taurocholate into the AP model group.The ADSCs treatment group received intravenous injections of ADSCs immediately following surgery,while the CM treatment group re-ceived conditioned medium preparations.Pancreatic tissue was collected 24 hours post-surgery,and changes in the CHOP/Bcl-2 pathway were assessed using histopathology,transmission electron microscopy,western blotting,fluorescence quantification,immunofluorescence,and TUNEL stai-ning.The results indicated that AP induced significant interstitial edema,hemorrhage,inflammato-ry cell infiltration,chromatin contraction,and endoplasmic reticulum swelling,the expression lev-els of GRP78 and CHOP were found to be elevated,whereas the expression of Bcl-2 was downreg-ulated.Additionally,the expression levels of BAX,JNK,Caspase-3,and Caspase-12 increased,leading to an increased rate of cell apoptosis.Such changes result in an elevated apoptosis rate and a further decrease in Bcl-2 expression.Both ADSCs and CM therapy were found to alleviate the path-ological damage in pancreatic tissue,resulting in downregulation of CHOP and apoptosis-related markers,upregulation of Bcl-2,and a reduction in the apoptosis rate.The results of this study sug-gest that ADSCs may mitigate acute pancreatic injury induced by trypsin and sodium taurocholate in AP dogs by modulating the CHOP/Bcl-2 pathway.Targeted modulation of the transcriptional activity of CHOP may offer novel therapeutic approaches for AP.