Quantum Dots-based Anti-swine Viral Materials In Vitro Screening And Molecular Mechanism Study

The source of animal-derived food safety is breeding.At present,the source pollution of breeding in China is more and more damaging to food safety.Therefore,the solution to food safety problems depends largely on the strict control at the source.The three systemic diseases of respiration,multiplication and digestion of pigs typified by pseudorabies virus,porcine reproductive and respiratory syndrome virus and porcine epidemic diarrhea virus seriously endanger the current pig breeding industry and cause enormous economic losses and serious troubles to the global pig industry as well as animal-derived food safety poses a huge safety risk.The traditional methods of prevention and treatment of swine viral diseases mainly rely on the combination of vaccine immunization and integrated management of biosecurity in farms.However,the evolution of variation in swine virus now frequent,the targeted vaccine development and production is seriously lagging behind,resulting in clinical use of immunoprotection ineffective.Secondly,different from the bacterial infection,due to the lack of specific antiviral drugs,which makes the prevention of viral infection is more complicated.Thus,it is of great practical significance to develop new,safe,efficient and low-cost anti-swine virus drugs for the prevention and treatment of foodborne animal diseases.As a zero-dimensional nanomaterial,quantum dots(QDs)mainly include semiconductor quantum dots,single-element quantum dots(C,Ag,Au)and other relevant forms.Due to their unique physicochemical properties,QDs has important application value in various fields such as food safety inspection,biomedicine,optoelectronics.Recently,the antimicrobial activity of QDs is one of the heated topics in the field of biological applications.Nevertheless,the research on the application of foodborne animal viruses is still infrequent.This paper is mainly based on the design,screening of antiviral activity of nanomaterials and explored the molecular mechanism of antiviral,so as to provide a theoretical basis for the future development of green antiviral agents.The contents of the full text are summarized as follows:1.Study on the antiviral effect of cadmium telluride quantum dots on porcine pseudorabies virusGlutathione-modified Cd Te quantum dots(GSH-Cd Te QDs)is prepared,the antiviral activity and antiviral mechanism of GSH-Cd Te QDs against PRV are discussed.One-step growth curve and fluorescence colocalization analyses indicate that Cd Te QDs inhibited PRV multiplication in the early stage of virus replication cycle by suppressing the invasion,but has no significant effect on the PRV penetration.Fluorescence spectrum analysis indicates that the size of QDs is reduced gradually after the addition of PRV within 30 mins,indicating that there is indeed an interaction between PRV and Cd Te QDs.In mechanism,release of Cd2+ was detected during the interaction of QDs and PRV,resulting in a decreased number of viruses which can infect cells.Additionally,the structure of viral surface proteins is altered by Cd Te QDs adsorbed on the virus surface,leading to the inhibition of virus replication.This study provides a basis for QDs-labeled virus research.2.Study on the antiviral effect of carbon quantum dots of polyethyleneimine on porcine pseudorabies virus and porcine reproductive and respiratory syndrome virusWe investigate the effect of CDs on the replication of virus by using pseudorabies virus(PRV)and porcine reproductive and respiratory syndrome virus(PRRSV)as the models of DNA virus and RNA virus,respectively.Analyses of virus titers and the expression of viral proteins demonstrated that cells treated with CDs can significantly inhibit the multiplication of PRV and PRRSV.In mechanism,CDs treatment dramatically induced interferon-?(IFN-?)production and the expression of IFN-stimulating genes(ISGs)which in turn inhibited virus replication.Taken together,these data provide the theoretical basis for further study on CDs as a new antiviral agent,and the results of this section are of great reference for understanding and study the antiviral mechanism of CDs on many other viruses.3.Study on the antiviral effect of carbon quantum dots of curcumin on swine epidemic diarrhea virus.Here,we report a one-step method to use curcumin,a polyphenolic compound extracted from turmeric rhizomes,for preparation of uniform and stable cationic carbon dots(CCM-CDs)with antiviral properties.The effect of as-prepared CCM-CDs on virus replication was investigated by using porcine epidemic diarrhea virus(PEDV)as a model of coronavirus.The cationic CCM-CDs treatment was found to significantly inhibit the multiplication of PEDV in the cells.In mechanism,the CCM-CDs treatment was found to inhibit viral entry by changing the structure of viral surface proteins and suppress the synthesis of viral negative-strand RNA,viral budding as well as the accumulation of reactive oxygen species(ROS)by PEDV.Furthermore,the experimental results also show that CCM-CDs can up-regulate the expression of interferon and proinflammatory cytokines and activate their own antiviral activity.These results provide a novel clue to improve the antiviral activity of herbs.4.Antiviral study of silver sulfide quantum dots on porcine epidemic diarrhea virusThis study described a one-pot method to prepare GSH capped-Ag2 S QDs.We demonstrated for the first time that Ag2 S QDs had remarkable antiviral activity against PEDV infection.The study of underlying molecular mechanisms indicated that Ag2 S QDs treatment inhibited the synthesis of viral negative-strand RNA and viral budding.Meanwhile,we also found that Ag2 S QDs up-regulated the production of IFN-stimulating genes(ISGs)and the expression of pro-inflammation cytokines and activated the downstream antiviral response pathway.Combining the above results with the good biocompatibility of Ag2 S QDs,it provides an experimental basis for further exploitation of Ag2 S QDs as a potential and highly effective the antiviral therapy in vivo.Additionally,given that SARS,MERS and PEDV belong to the coronavirus family,our results provide the reference for the development of anti-SARS or anti-MERS nano-drugs.