18 results about "Infection experiment" patented technology

The invention belongs to the technical field of biology, and particularly relates to a porcine epidemic diarrhea virus broad-spectrum neutralizing antibody and application thereof. A porcine epidemic diarrhea virus broad-spectrum neutralizing antibody 6G2 is screened, the virus neutralizing activity of the antibody is evaluated through a cell model, and it is found that the antibody can effectively block infection of G1a, G1b, G2a, G2b, G2c and S-INDEL (porcine epidemic diarrhea virus) gene subtype strains with high epidemic rate on cells. Further, animal infection experiments of pigs prove that the neutralizing antibody provided by the invention has good prevention and treatment effects on the porcine epidemic diarrhea virus, and has important significance on improving the capability of preventing and controlling porcine epidemic diarrhea in a pig farm.

The invention discloses a primer and probe combination and method for detecting the content of vRNA, cRNA and mRNA of influenza viruses H7N9 in vivo and application of the primer and probe combination and method, and belongs to the technical field of biology. In order to solve the technical problem that the prior art can only detect vRNA, cRNA and mRNA of influenza viruses on in-vitro cell lines and cannot adapt to animal in-vivo infection experiments with complex template quantities, the invention designs a primer and probe combination for detecting in-vivo H7N9 influenza virus PB2 or NA gene vRNA, cRNA and mRNA. The primer and probe combination comprises a reverse transcription primer, a fluorescent quantitative PCR primer and a probe, the obtained primer and probe combination and a fluorescent quantitative PCR technology are utilized to measure the vRNA content, the cRNA content and the mRNA content of PB2 and NA genes of the H7N9 virus in a mouse body, and an experimental scheme is provided for researching the real copying condition of the influenza virus H7N9 in the body.

The application provides a kind of nasal mucosa in vitro culture method and culture fluid, the composition of the culture fluid includes Wnt / β-catenin signal pathway activator 0.1-20 μg / ml, fibroblast growth factor 10-150 ng / ml, TGF-β inhibitor 0.02-3 μg / ml, ROCK inhibitor 0.1-100 μmol / L, P38 MAPK inhibitor 0.1-1 μmol / L, serum-free additive 1X, N-acetyl cysteine 1-10 mmol / L, nicotinamide 1-20 mmol / L, GlutaMax additive 1X, antibiotic, DMEM / F12 culture medium 1X.The application can carry out in vitro culture to nasal mucosa, can keep at least 2 weeks of activity, and have complete epithelial barrier and immune system, can realize ex vivo nasal mucosa virus infection experiment.

The application provides a method for constructing an immortalized bovine nasopharyngeal tonsil epithelial cell line and application, and belongs to the technical field of cell engineering. The healthy yellow bovine nasopharyngeal tonsil is used as a material, and the primary epithelial cells are separated by enzyme digestion. The 3rd to 4th generation cells are taken, infected with SV40 T lentivirus (MOI=80), and screened by 1.5 μg / mL puromycin to obtain a stable immortalized cell line. The cell line is continuously passaged to the 50th generation and still stably expresses SV40LT protein and epithelial specific markers CD326, CD324 and KRT8, maintains a typical pavement stone-like morphology, normal proliferation and no malignant transformation. Infection experiments show that the cell is highly sensitive to FMDV, supports efficient replication, and the virus titer can reach 10 7.5 TCID 50 / mL. The application overcomes the defects of the existing immortalized bovine nasopharyngeal tonsil epithelial cell model, such as limited source, large batch difference, low sensitivity and poor persistence, and provides a stable and reliable in vitro model for the research of foot-and-mouth disease prevention and control related mechanisms, drug screening and vaccine development.

The application provides an animal immune evaluation method based on a Lutzomyia longipalpis infection model, and comprises the following steps: S1, experimental animal preparation and screening; S2, Lutzomyia longipalpis preparation and quality verification; S3, Lutzomyia longipalpis infection of experimental animals; S4, immune related index detection; S5, animal immune function evaluation; and S6, repeatability verification and data summarization. The application realizes systematic and objective evaluation of the effect of immune candidate drugs.

The invention relates to a recombinant kunitz protein of third-generation botryosphaeria formosa as well as a preparation method and application of the recombinant kunitz protein, and belongs to the technical field of fish parasite protein expression and function application research. The serine protease inhibitor of the third-generation botryosphaeria formosa is a GcKSI protein, and the amino acid sequence of the GcKSI protein is as shown in SEQ ID NO: 2. According to the invention, the amino acid sequence of the GcKSI protein is optimized, and the GcKSI recombinant protein rGcKSI is obtained through prokaryotic expression. The rGcKSI inhibits complement activity of host fish in vitro and has an obvious inhibition effect on serine protease, after injection immunization of the rGcKSI and third-generation insect infection experiments, the infection rate and the average infection intensity of the rGcKSI are obviously lower than those of a control group, and it is proved that the rGcKSI has good immunoprotectiveness on third-generation insect infection, and the rGcKSI can be used as an immunopotentiator for the third-generation insect infection of the tilapia. The GcKSI gene of the serine protease inhibitor and the GcKSI protein coded by the GcKSI gene can be used as new targets for drug research and development.

The utility model relates to a cage for a small animal transmission infection experiment, and relates to the technical field of cages, and the cage comprises a first cage used for placing infected animals and healthy animals and provided with an air inlet in a communicating manner; the second cage is used for placing healthy animals, is arranged beside the first cage and is communicated with the first cage, and the communication part is isolated by two layers of separation nets; the third cage is used for placing healthy animals, is connected with the second cage through a transmission pipeline, and is communicated with an air outlet; a plurality of animal isolation cavities which are isolated from one another are formed in the second cage and the third cage. By arranging the cage suitable for the small animal transmission infection experiment, the requirement of the small animal transmission infection experiment is met.

The application discloses a kind of siRNA and antiviral application of targeting swine epidemic diarrhea virus Nsp9, belong to the field of biotechnology.The application designs a kind of siRNA targeting PEDV Nsp9, the nucleotide sequence of the siRNA sense strand is as shown in SEQ ID NO.3, the nucleotide sequence of the siRNA antisense strand is as shown in SEQ ID NO.4.It is proved by cell transfection experiment and virus infection experiment that the siRNA prepared in the application can significantly reduce the replication infection of PEDV in cells, effectively inhibit the expression of virus, and play an antiviral role;And the siRNA has no cytotoxicity, and has extensive application prospect.

The present application relates to a guppy trichodinid third generation recombinant kunitz protein and a preparation method and application thereof, and belongs to the technical field of fish parasite protein expression and functional application research.The serine protease inhibitor of the guppy trichodinid third generation in the present application is a GcKSI protein, and the amino acid sequence of the GcKSI protein is shown as SEQ ID NO:2.The amino acid sequence of the GcKSI protein is optimized in the present application, and a GcKSI recombinant protein rGcKSI is obtained through prokaryotic expression.rGcKSI can inhibit the complement activity of a host fish in vitro, and has an obvious inhibitory effect on serine protease.The infection rate and average infection intensity of rohu fish injected with rGcKSI and then subjected to trichodinid infection experiment are significantly lower than those of a control group, proving that rGcKSI has good immunoprotective properties for trichodinid infection, and indicating that the serine protease inhibitor GcKSI gene and the GcKSI protein encoded by the GcKSI gene can be used as a new target for drug research and development.

The invention discloses a reagent composition for improving lentivirus infection NK cell efficiency and application thereof. The reagent combination comprises a suspension culture type 293T cell, a lentivirus transfer plasmid, a lentivirus packaging plasmid and a lentivirus packaging helper plasmid. The lentivirus prepared by using the suspension culture type 293T cell package can significantly improve the NK cell infection efficiency of the lentivirus, and compared with the lentivirus prepared by using adherent cells, the virus titer is higher, the culture medium does not need to be added with serum, and the use amount of the lentivirus in a subsequent infection experiment can be reduced, so that the cost is saved, and the cost is reduced. In addition, operation is easy and convenient, time is saved, and large-scale production is facilitated.

The present invention relates to molecular biology and aquaculture breeding, specifically to a method for obtaining a PRMT2 gene mutant by knocking out the gene based on CRISPR / Cas9 technology, and establishing an antibacterial strain of tilapia with a PRMT2 knockout. By knocking out this gene, a tilapia strain resistant to Streptococcus agalactiae can be obtained. Infection experiments revealed that tilapia with a PRMT2 knockout gene exhibited enhanced antibacterial activity compared to wild-type tilapia. This invention provides an important model for disease-resistant tilapia breeding and offers gene targets and new research directions for creating more disease-resistant fish strains and varieties.

The utility model discloses a centrifugal device for DF1 cell infection experiment, which comprises a support frame and a support disc connected to the top of the support frame, the center of the support disc is rotatably connected with a centrifugal shaft, a support plate is connected with a spring I for supporting the support plate, the top of the centrifugal shaft is connected with a pressing mechanism for pressing a plurality of test tubes, and the spring I is connected with a spring II for supporting the support plate. The pressing mechanism comprises a connecting rod, a rotating cylinder, a movable disc, a sliding block, a second spring, a plurality of L-shaped plates and a plurality of glands, the two ends of each L-shaped plate are connected with the rotating cylinder and the corresponding glands, the sliding block is used for guiding the movable disc, and the second spring is used for driving the movable disc to move in the direction close to the centrifugal shaft. The top of the centrifugal shaft is connected with a locking mechanism used for locking the L-shaped plate. The stability of a plurality of glands can be improved, a plurality of test tubes can be synchronously pressed and fixed, the installation time of the test tubes is shortened, and the working efficiency is improved.

The utility model relates to a delivery window for a transmission infection experiment device, and relates to the technical field of delivery windows. The cabin door is arranged at the communication part of the cabin body and the experimental device and is hinged with the cabin body; the opening-closing assembly is used for driving the cabin door to rotate along the hinged position to achieve opening-closing control of the communicating position of the cabin body and the experimental device. By arranging the delivery window facilitating opening and closing of the cabin door, the convenience of inputting or outputting articles through the delivery window is effectively improved.

The invention provides an animal immunity evaluation method based on a chlamys farreri infection model. The animal immunity evaluation method comprises the following steps: S1, preparing and screening experimental animals; s2, preparation and quality verification of the chlamys farreri; s3, infecting experimental animals with the chlamys farreri; s4, detecting immune related indexes; s5, animal immune function evaluation; and S6, carrying out repeatability verification and data summarization. According to the invention, systematic and objective evaluation of the effect of the immune candidate drug is realized.

The invention discloses a pseudomonas plecoglossicida recombinant strain for expressing green fluorescence as well as a construction method and application of the pseudomonas plecoglossicida recombinant strain. The construction method comprises the following steps: constructing a pBBR1-GFP plasmid, and transforming the pBBR1-GFP plasmid into pseudomonas plecoglossa NB2011, so as to obtain a recombinant strain P. plecoglossa NB2011 / pBBR1-GFP capable of stably expressing green fluorescence. The recombinant strain shows green fluorescence when being observed under a fluorescence microscope, the plasmid stability rate can reach 100% after 30 generations of passage, the strain is constructed through an electrotransformation method, positive clones are screened through chloramphenicol, the strain has high hereditary stability, and through an infection experiment, the strain has good clinical application prospects. The fluorescent recombinant strain shows good visualization ability in mouse macrophages J774A.1 and juvenile zebrafish, and the interaction between the strain and host cells and tissues can be observed in real time. The invention provides a visual and stable fluorescence labeling tool, can be used for researching the pathogenic mechanism of pseudomonas plecoglossicida, and provides a new method and technical means for researching the interaction between pathogenic bacteria and hosts.

The invention relates to the technical field of tools for infection experiments, in particular to a cell culture dish for infection experiments. According to the cell culture dish for the infection experiment, the technical problem that a cell culture dish in the prior art cannot be independently replaced or maintained is solved. The invention discloses a cell culture dish for infection experiments. The cell culture dish comprises a frame, the culture device is arranged on the frame; the culture device is arranged on the frame through the connector; wherein the incubator comprises a body and a cavity formed in the body, and the body is connected to the connector in an inserted mode; and the body of the incubator is inserted into the positioning cylinder of the connector. And the positioning cylinder plays a role in positioning and fixing the incubator, so that the position of the incubator on the connector is ensured to be accurate and stable. The incubator can be conveniently taken down from or installed on the connector through the inserting mode, and independent operation of the incubator is achieved.

The invention discloses a quantitative detection method of fungal cells and application thereof, and belongs to the technical field of microorganisms. The method comprises the following steps: culturing fungi to be detected in a liquid culture medium for 2-7 days; selecting hypha clusters not smaller than 0.5 cm * 0.5 cm, adding normal saline, and fully grinding to obtain hypha suspension; filtering the obtained hypha suspension by using a filter screen with the aperture of 70-100 microns, and collecting the filtered hypha suspension; and adding the obtained hypha suspension to a blood cell counting plate, and observing and counting hyphae of fungi by using a microscope. The detection method can be used for counting fungi with weak sporulation and fungi without sporulation, and can be used for downstream fungi quantitative related experiments, such as antifungal drug sensitivity detection experiments, fungus in-vitro infection experiments, animal infection model experiments and the like.

This invention provides the application of norzelamin in the preparation of NDM-1 enzyme inhibitors. Through cefotaxime hydrolysis assays, checkerboard minimum inhibitory concentration (MIC) tests, growth curves, bactericidal curves, hemolysis tests, and *Gnaphalium affine* infection experiments, it was demonstrated that norzelamin can inhibit NDM-1 enzyme activity and exhibits good synergistic antibacterial activity with the carbapenem antibiotic meropenem, enhancing the protective effect of meropenem against *Gnaphalium affine* larval infection models. Therefore, norzelamin, as a potential adjuvant for β-lactam antibiotics, can enhance the antibacterial effect of β-lactam antibiotics by inhibiting NDM-1 enzyme activity, which is of great significance for the clinical development of safe and effective β-lactam antibiotic adjuvants.