18 results about "Hemagglutination" patented technology

This invention discloses a method for detecting antigen content, comprising the following steps: diluting the test sample and a reference sample to specific concentrations; serially diluting the test sample and reference sample to specific concentrations using a diluent on a 96-well hemagglutination plate; adding sensitized red blood cell suspension to wells of different dilutions of the test sample and reference sample, mixing, allowing to stand, and then determining the agglutination results of each well; scoring and recording the agglutination results of each well; summing the scores of each test sample and recording it as A, and summing the total scores of each reference sample and recording it as B; calculating the antigen content of the test sample according to the formula: antigen content of the reference sample × 2. (A‑B) / 16 This method is convenient and fast. The test results are calculated using the self-developed method and compared with the test results of the reference sample, which can obtain relatively accurate test results and solve the problem of inconsistent test results of different batches of sensitized red blood cell suspensions.

The invention discloses a recombinant nano antibody of a waterfowl H9N2 avian influenza virus, a recombinant expression vector, a recombinant strain and application thereof, and relates to the field of biology. The amino acid sequence of the recombinant nano antibody is SEQ ID NO: 2, and the nucleotide sequence of the recombinant nano antibody is SEQ ID NO: 1. The invention provides a recombinant expression vector containing the coding gene of the recombinant nano-antibody and a recombinant strain for expressing the recombinant nano-antibody. The recombinant nano antibody is applied to preparation of a waterfowl H9N2 avian influenza resisting medicine or a waterfowl H9N2 avian influenza diagnostic reagent. The yield of the recombinant nano antibody reaches 1.5 g / L, the hemagglutination inhibition activity titer for resisting the waterfowl H9N2 avian influenza virus is 4 log2, and the recombinant nano antibody has remarkable biological activity and can be used for preparing a novel nano antibody preparation for preventing and / or treating the waterfowl H9N2 avian influenza.

The present invention belongs to the field of interferon genetic engineering, and discloses recombinant pigeon alpha interferon and its application in the preparation of medicines for resisting pigeon paramyxovirus infection. The present invention constructs recombinant pigeon interferon piINF 5, realizes efficient expression and purification in CHO cell expression system, significantly prolongs its half-life and improves stability. Recombinant pigeon interferon piINF 5 has no toxic effect on DF1 and VERO cells, and can effectively stimulate the transcription level of interferon-stimulated genes, can significantly inhibit the replication of pigeon paramyxovirus, reduce viral copy number and hemagglutination value. In vivo animal attack experiment shows that the recombinant pigeon interferon piINF 5 can well protect pigeons from the attack of pigeon paramyxovirus, and the survival rate reaches 80%, and there is no detoxification in the first five days after the attack, and only 20% of animals have detoxification in the later stage. The present invention provides an efficient and stable new drug selection for the treatment of pigeon paramyxovirus disease, with good commercial application prospects.

The invention relates to the technical field of biology, and discloses an influenza A virus H5 protein mutant and application thereof. In order to solve the problems of weak cross immune response to epidemic strains, insufficient stability of wild type HA protein, low immunogenicity and the like of the existing H5N1 vaccine, a stable soluble H5 protein mutant is constructed through a sequence modification strategy. Specifically, the 332th to 380th amino acids in the HA protein of a wild type influenza A virus H5N1 are replaced by SPGCAT, and point mutations T386C, L418P and H456P are introduced to obtain the mutant. The mutant can significantly improve the structural stability of trimer protein, improve the expression level of recombinant protein, broaden the cross protection spectrum, enhance the level of immunogenic hemagglutination inhibition antibodies and improve immune response balance.

The present invention describes hemagglutination inhibition (HAI) assay methods to determine candidate subunit protein vaccines in the absence of using source viruses.

The present invention belongs to the technical field of biomedicine, and specifically relates to a recombinant influenza virus protein, a vaccine, and a preparation method therefor and the use thereof. To overcome the defects of existing influenza vaccines with respect to safety and high toxic side effects, a recombinant influenza virus protein is provided, which has an amino acid sequence as shown in at least one of SEQ ID No. 1 to SEQ ID No. 6. Recombinant hemagglutinin proteins of H1N1 and H3N2 subtypes, and Victoria and Yamagata lineages are expressed and purified by means of an insect baculovirus expression system, and are mixed with an adjuvant to prepare a highly immunogenic recombinant bivalent, trivalent or quadrivalent recombinant influenza virus protein vaccine. The prepared vaccine can induce high levels of specific IgG antibodies and hemagglutination-inhibiting neutralizing antibodies, the addition of adjuvant WGa01 improves the immunogenicity of the vaccine, and the provided vaccine is suitable for people allergic to eggs and has high safety.

The invention discloses an anti-influenza A virus micropeptide uYIPF2 coded by an upstream open reading frame of a YIPF2 gene and application thereof, and relates to the technical field of biological medicines. The micropeptide uYIPF2 is coded by an upstream open reading frame (uORF) of a YIPF2 gene, contains 87 amino acids, and has a specific sequence as shown in SEQ ID No.1. A hemagglutination test and a plaque test prove that the micropeptide uYIPF2 can significantly reduce the HA titer and the virus load of the influenza A virus, and can significantly inhibit the replication of the influenza A virus. The invention reveals that the uYIPF2 micro-peptide has an anti-influenza A virus biological function for the first time, and provides application of the uYIPF2 micro-peptide in preparation of drugs for preventing and treating influenza A virus infection. The invention provides a brand-new drug target and a treatment strategy for the field of flu prevention and treatment.

The invention discloses a histophilic somniphilus, a hemagglutination antigen, a hemagglutination inhibition antibody detection method, a kit and application of the histophilic somniphilus and the hemagglutination antigen. The method comprises the following steps: screening a histophilic sleep bacteria Yunnan isolate ZY25055 with high hemagglutination activity, culturing, and carrying out beta-propiolactone inactivation to prepare the histophilic sleep bacteria hemagglutination antigen. 1% hydroformylated sheep red blood cells are prepared by collecting sheep blood. Immunizing goat posterior jugular vein blood sampling with beta-propiolactone inactivated histophilic sleep bacteria liquid for three times, and centrifugally separating serum to prepare histophilic sleep bacteria standard positive serum. The method and the kit for detecting the histophilic sleeping bacteria hemagglutination inhibition antibody are established by utilizing the prepared histophilic sleeping bacteria hemagglutination antigen, 1% hydroformylated sheep red blood cells and histophilic sleeping bacteria standard positive serum, the method has no cross reaction with positive serum of common pathogens of cattle and sheep, and the method has the advantages of strong specificity, simplicity and convenience in operation, no need of complex equipment and the like, and can be used for detecting the histophilic sleeping bacteria hemagglutination inhibition antibody. The kit can be used for detecting the histophilic somniphilus antibody in bovine serum, sheep serum and goat serum.

The present invention describes hemagglutination inhibition (HAI) assay methods to determine candidate subunit protein vaccines in the absence of using source viruses.

The invention provides a method for preparing a Newcastle disease virus antigen by a cell suspension culture process, and relates to the technical field of virus antigen and vaccine preparation. The suspension culture method comprises the following steps: inoculating full-suspension Newcastle disease virus production cells into an F807k basal culture medium according to a certain density for cell culture, adding an NF01d supplementary culture medium after the cell culture is performed for 70-74 hours, adding an F808Vb supplementary culture medium after the cell culture is performed for 94-98 hours, inoculating Newcastle disease virus according to a virus inoculation amount of 0.1-0.5%, and culturing for 20-30 hours. And 38-42 hours after virus inoculation, adding the NF01d supplementary culture medium again, and expressing the Newcastle disease virus antigen at 28-38 DEG C. According to the optimized full-suspension culture process, higher antigen expression quantity can be obtained, the virus yield is improved, the hemagglutination titer of the obtained Newcastle disease virus antigen reaches 12log2 for the first time, and the protective efficacy is improved.

The present invention relates to the field of biological vaccine research and development technology, and in particular, to a VSV vector-based highly pathogenic H5 subtype avian influenza inactivated vaccine and a method for preparing same. The method comprises: using a vesicular stomatitis virus with the deletion of the surface envelope protein gene as a vector, inserting the NA gene and the HA gene of an H5 subtype highly pathogenic avian influenza virus strain between the M gene and the L gene of the vector in the form of an expression cassette, and acquiring a recombinant virus by means of rescue via reverse genetic technology; inoculating the recombinant virus into susceptible cells, culturing for replication and proliferation, and then harvesting a viral solution; inactivating the viral solution to acquire an inactivated viral solution; and adding the inactivated viral solution to a pharmaceutically or veterinarily acceptable carrier, excipient, medium, or adjuvant to acquire an inactivated vaccine. The provided H5 subtype avian influenza inactivated vaccine can induce a high hemagglutination inhibition titer of avian influenza virus on day 21 after chick immunization. The provided inactivated vaccine has good safety and immunogenicity.

The invention discloses a recombinant nano antibody for resisting H9 subtype avian influenza virus HA protein and application of the recombinant nano antibody, and relates to the field of bioengineering, and the amino acid sequence of the recombinant nano antibody is SEQ ID NO: 2; the nucleotide sequence for coding the amino acid sequence of the recombinant nano antibody is SEQ ID NO: 1. The yield of the recombinant nano-antibody is 1.84 mg / mL, the recombinant nano-antibody is only specifically combined with H9 virus and HA protein, has hemagglutination inhibition activity and HI titer of 8.3 log2, is the first nano-antibody with hemagglutination inhibition activity reported at present, has half effective inhibition concentration IC50 of 16.31 mu g / mL, can significantly reduce the detoxification level of the virus in chicks, has high biological activity, and can be used for preparing the recombinant nano-antibody. The strain can be applied to prevention and / or treatment of H9 subtype avian influenza, provides a novel, efficient and customizable biological preparation platform for prevention and control of avian influenza, and has important scientific research value and industrialization prospect.

Provided are an antibody or an antigen-binding fragment thereof that specifically recognizes CD47 and methods of making the same and using the same. The antibodies provided herein exhibit both induction of phagocytosis of cancer cells and have very low to no hemagglutination and phagocytosis of RBCs, showing improved efficacy to toxicity ratio for cancer treatment.

The present invention relates to a chimera formed of peptide epithedes derived from hemagglutinin and neuraminidase characterized in that it consists of SEQ ID NO.4.

The utility model provides an avian influenza hemagglutination inhibition test analyzer, which comprises a rack, and further comprises a carrier, a rotating assembly, a circulating assembly, a light source plate and a mounting plate, and a plurality of carrier holes are formed in the carrier and are used for placing hemagglutination plates to be detected. By means of the design, the device has more advantages in batch testing, and the working efficiency is improved. According to the design, the accuracy and the efficiency of an avian influenza hemagglutination inhibition test are improved, the time and the labor cost of a laboratory can be saved, the manual operation is reduced, the automation degree of the test is improved, the test efficiency is improved, the personal error is reduced, and a shot sample result can be recorded; and the work of scientific research and clinical detection is more efficient and quicker. Through reasonable structural design and intelligent function configuration, an efficient, accurate and reliable solution is provided for related research and clinical detection, and the requirements of modern laboratories for diversification and high efficiency of equipment are met.

The invention discloses an anti-H7N9 influenza virus monoclonal antibody and an application thereof. The anti-H7N9 influenza virus monoclonal antibody disclosed by the invention has relatively high affinity with various H7N9 viruses, the affinity with H7N9-AH13HA is at a pM level, and the affinity with H7N9-SF003HA and H7N9-SD12HA is at an nM level; the neutralizing activity (IC50) on H7N9 / AH13 and H7N1 / SF003 can reach 0.01 mu g / mL, and the neutralizing activity on H7N9 / AH13 and H7N1 / SF003 can reach 0.005 mu g / mL; the hemagglutination titer to H7N9 / AH13 is 0.97 mu g / mL, the hemagglutination titer to H7N1 / SF003 is 1.95 mu g / mL, and both the H7N9 / AH13 and the SF003 have very high neutralization titers; the kit can be used for detecting the H7N9 influenza virus and / or the HA protein of the H7N9 influenza virus, and preventing and / or treating diseases caused by the H7N9 influenza virus.

This invention relates to the field of bioengineering, and more particularly to sgRNA, MDCK cells, and their applications. This invention provides sgRNA having the nucleotide sequences shown in SEQ ID NO:1 to SEQ ID NO:4. This invention employs a CRISPR-Cas9 gene editing method, which, compared to existing RNAi methods, offers higher specificity and lower off-target risk. Compared to MDCK cells, PCR detection showed a reduction of over 90% in RNA levels in IRF7- / - cells, Western blotting showed a significant decrease in IRF7 protein expression, and viral hemagglutination assays showed higher titers for influenza virus compared to the original cells. Tumorigenicity assays showed that the gene knockout cells retained low tumorigenicity. Compared to existing technologies, the cells of this invention exhibit both low tumorigenicity and significantly increased viral yield, making them suitable for influenza vaccine production.

The invention discloses a novel red blood cell agglutination and red blood cell agglutination inhibition test detection method, which comprises the following steps of: after adding a to-be-detected sample into 1% of pig red blood cell suspension to react, sucking 50 microliters of supernatant liquid into a 96-hole ELISA (enzyme-linked immunosorbent assay) plate, and reading at the wavelength of 450 nm by using a microplate reader; calculating the average value of the OD values of the four multiple holes of each dilution degree of the sample to be detected, substituting the dilution times and the average value of the OD values into fitting software ELISACalc, and fitting by adopting a four-parameter fitting mode to obtain an S-shaped curve and an equation; the linear parameter R2 of the obtained S-shaped curve is observed, and when R2 is larger than or equal to 0.97, the linear parameter meets the requirement, and the test result is credible; and substituting the OD average value of the control sample into the equation to obtain a corresponding dilution multiple, namely the erythrocyte agglutination valence or erythrocyte agglutination inhibition valence of the sample to be detected. The scientificity and accuracy of the erythrocyte agglutination and erythrocyte agglutination inhibition test method are improved.