352 results about "Titer" patented technology

The invention discloses a cat measles virus specific monoclonal antibody and application thereof, the monoclonal antibody is prepared by immunizing a cat measles virus N protein, and the monoclonal antibody specifically recognizes the cat measles virus N protein. The recognized feline measles virus N protein comprises a feline measles virus N protein-N fragment with a nucleotide sequence as shown in SEQ ID NO: 1 and a feline measles virus N protein-C fragment with a nucleotide sequence as shown in SEQ ID NO: 2. The monoclonal antibody provided by the invention can specifically recognize the feline measles virus N protein and is high in titer, good in affinity and high in sensitivity, a detection kit prepared based on the antibody can effectively detect feline measles viruses in body fluids such as cat blood and urine, and a technical support is provided for epidemiological monitoring and diagnosis of feline measles virus infection.

The invention discloses an anti-human hepatitis B e antigen monoclonal antibody and application thereof, and relates to the technical field of hepatitis B detection. In a heavy chain variable region of the monoclonal antibody, an amino acid sequence of a complementarity determining region CDR1-3 is as shown in SEQ ID NO.1-3 or has at least 95% of homology with the sequence as shown in SEQ ID NO.1-3; in the light chain variable region, amino acid sequences of complementary determining regions CDR1 and CDR3 are shown as SEQ ID NO.4 and SEQ ID NO.5 or have at least 95% of homology with the sequences shown as SEQ ID NO.4 and SEQ ID NO.5, and an amino acid sequence of a complementary determining region CDR2 is FAS. The monoclonal antibody provided by the invention can well recognize a natural hepatitis B e antigen, and the titer of a supernatant cultured by a B cell can reach 1: 10000, so that the monoclonal antibody can be completely applied to detection research of the human hepatitis B e antigen. The chemiluminescence reagent prepared by using the monoclonal antibody has the advantages of high specificity, strong anti-interference capability, high detection sensitivity, good stability and the like, almost has no leak detection, and can replace an imported reagent.

The invention discloses preparation of an antibody capable of detecting multi-subtype KPC and application of a kit of the antibody, and belongs to the field of biological medicine. According to the kit for detecting the common subtypes of KPC and the application of the kit, the mouse antibodies are prepared through immunization of conserved antigen epitopes of all the subtypes of KPC, in-vitro screening and pairing are carried out in multiple modes, then an antibody pair which is good in specificity and high in affinity and can be combined with multiple subtypes is obtained, the titer of the two antibodies can reach one million or above, and the kit is high in specificity, good in affinity and capable of being used for detecting the common subtypes of KPC. Amino acid sequences of a heavy chain variable region and a light chain variable region are obtained through sequencing, and rapid and stable expression can be realized after recombination. The product for detecting the carbapenem KPC is developed on the basis of an immunochromatography platform, and the kit has the advantages of high sensitivity, good specificity, good stability, capability of covering most epidemic KPC subtypes and rapidness and convenience in detection, and provides important help for clinical auxiliary diagnosis and medication guidance.

The invention relates to a Nipah virus N protein specific monoclonal antibody as well as a preparation method and application thereof. The nipah virus specific monoclonal antibody is prepared by immunizing nipah virus N protein, the amino acid sequence of the nipah virus N protein is as shown in SEQ ID NO.2, the nipah virus N protein is obtained by transcription of a nipah virus N gene, and the nucleotide sequence of the nipah virus N gene is as shown in SEQ ID NO.1. The nipah virus specific monoclonal antibody has the advantages that the nipah virus specific monoclonal antibody is prepared by immunizing the nipah virus N protein; the monoclonal antibody with the nipah virus N protein specificity can be specifically combined with the nipah virus N protein and is high in titer and good in affinity, meanwhile, a detection kit prepared based on the antibody can effectively carry out nipah virus detection, and technical support can be provided for epidemiological monitoring and diagnosis of nipah virus infection.

The invention discloses preparation of a human CD56 immune phage display antibody library, which comprises the following steps: S1, animal immunization: expressing recombinant hCD56 protein in escherichia coli, then immunizing a Balb / c mouse, and detecting immune titer; s2, splenocyte preparation: extracting RNA (Ribonucleic Acid) of immune mouse spleen cells, and performing reverse transcription to obtain cDNA (Complementary Deoxyribonucleic Acid); s3, preparation of an initial bacteriophage display library: amplifying a heavy chain variable region and a light chain variable region by using a PCR technology, and then assembling to form scFv; constructing scFv phagocytids, electrically transforming the scFv phagocytids into TG1 competent cells, and constructing a bacterial library; s4, constructing a phage single-chain library of the hCD56: infecting the bacterial library by using a helper phage M13K07, and constructing a phage single-chain antibody library; and S5, elutriation and screening of a phage library: specifically enriching a phage single-chain antibody library, screening positive clones from the phage single-chain antibody library, and determining a sequence. According to the invention, the human hCD56 antibody scFv sequence fragment can be screened out, and the research and development period is shortened.

The present invention belongs to the field of virus detection technology, and specifically relates to monoclonal antibodies with neutralizing activity against adenovirus type 5 and their uses. The monoclonal antibody 8B9 of the present invention can specifically recognize and neutralize adenovirus type 5, and the amino acid sequences of the heavy and light chain variable regions and their complementarity determining regions of the monoclonal antibody 8B9 are provided. The present invention also provides an in vitro neutralization activity assessment model based on HEK-293A cells. At a concentration as low as 3.3 μg / mL, the titer of the neutralizing activity against the virus stock solution after 6000-fold dilution is 7×10 4 TCID 50 / mL of virus has close to 100% neutralizing activity. After further humanization, it is expected to be developed into a neutralizing antibody drug for the treatment of diseases such as severe pneumonia caused by HADV-5 infection, filling the current lack of effective treatment options in this field and possessing significant scientific research value and clinical application prospects.

This invention discloses a monoclonal antibody against human hepatitis B e antigen and its application, relating to the field of hepatitis B detection technology. In the heavy chain variable region of the monoclonal antibody, the amino acid sequences of the complementarity-determining regions (CDR1-3) are as shown in SEQ ID NO. 1-3 or have at least 95% homology with the sequences shown in SEQ ID NO. 1-3; in the light chain variable region, the amino acid sequences of the complementarity-determining regions (CDR1 and CDR3) are as shown in SEQ ID NO. 4 and 5 or have at least 95% homology with the sequences shown in SEQ ID NO. 4 and 5, and the amino acid sequence of the complementarity-determining region (CDR2) is FAS. The monoclonal antibody provided by this invention can effectively recognize natural hepatitis B e antigen, and the titer of the supernatant from B cell culture can reach 1:10000, making it fully applicable to the detection and research of human hepatitis B e antigen. The chemiluminescent reagent prepared using the monoclonal antibody described in this invention has advantages such as high specificity, strong anti-interference ability, high detection sensitivity, and good stability, with almost no missed detections, and can replace imported reagents.

Methods and systems for monitoring and / or controlling production units used at various stages of biological product development and manufacturing are presented herein. In particular, in certain embodiments, the biological production monitoring and control techniques described herein utilize a mid-infrared (mid-IR) analyzer that is capable of obtaining mid-infrared spectral data from an aqueous sample in substantially real time. The techniques described herein can utilize this mid-infrared spectroscopic data to measure sample quality metrics, such as protein content, titer, secondary structure, aggregation, and the like, as well as viral and / or nucleic acid characteristics. Thus, sample quality metrics can be measured substantially in real time and / or continuously to assess, for example, the production quality of protein and gene therapeutic agents, and can be used by a control system to adjust and / or control process parameters to improve product quality, etc.

The invention discloses a hybridoma cell strain capable of secreting clonorchis sinensis monoclonal antibodies and application of the hybridoma cell strain, and belongs to the technical field of monoclonal antibodies. The invention aims to improve the sensitivity, specificity and titer of clonorchis sinensis monoclonal antibody detection. The invention provides a hybridoma cell strain capable of secreting clonorchis sinensis monoclonal antibodies, the hybridoma cell strain is preserved in China General Microbiological Culture Collection Center (CGMCC), the preservation number is CGMCC NO.46128, and the preservation time is November 6, 2024. The test strip provided by the invention is safe and harmless to an operator and does not cause pollution to the environment, so that the test strip has huge application potential and prospect in the market of clinical detection of clonorchiasis sinensis.

The invention discloses a surface antigen gene StSAG1 of Sarcocystis tenella, the nucleotide sequence of the surface antigen gene StSAG1 is as shown in SEQ ID NO: 1, and according to the analysis result of protein antigenicity and antigen epitope, the 686 bp-1175 bp segment of the StSAG1 gene is selected to construct a recombinant protein expression vector and engineering bacteria; the antigen disclosed by the invention has very strong antigenicity and specificity, and can be subjected to effective antigen-antibody reaction with an antibody generated in serum after sheep (Ovis aries) is infected with sarcosporidium tenella, so that diagnosis is realized; low-titer antibodies can be detected two weeks after infection, and the detection window period is obviously advanced; by adopting the ELISA detection method, a visual result can be directly obtained. The method breaks through the limitation of an infection window period, has the advantages of low cost, high sensitivity, simplicity and convenience in operation, no need of expensive instruments and analysis and the like, is suitable for field detection in primary laboratories and pastures, and is beneficial to industrial production and market popularization and application.

The present invention relates to the technical field of biomedicine. Specifically provided are a respiratory syncytial virus (RSV) Pre-F recombinant protein nanoparticle vaccine and a preparation method therefor. By performing amino acid mutation on an RSV Pre-F protein, and performing fusion expression on the mutated Pre-F protein and ferritin particles in eukaryotic cells, PreF-Ferritin fusion protein nanoparticles, in which eight Pre-F protein trimers are densely displayed on the surface of each ferritin particle, are obtained. By stabilizing and exposing antigen epitopes required to be displayed and disrupting or masking unrequired antigen epitopes, the PreF-Ferritin fusion protein nanoparticles effectively improve the immunogenicity and the production stability of the antigen. Experiments show that: when the PreF-Ferritin fusion protein is injected into mice, high-titer protective sera can be acquired, and the mice sera can yield relatively high neutralizing titers against RSV.

[00121] The present invention relates to a label-free, high throughput method for determining an infectious virus titer in an aqueous sample comprising infectious virus, wherein the method comprises detecting the kinetics of morphological cell alteration, such as cell rounding, following viral infection, determining a parameter defining the curve of the morphological cell alteration as a function of time post infection and determining the infectious virus titer based on a standard curve of the infectious virus at a known infectious titer.

The invention provides a safrole hapten and application of the safrole hapten in detection of safrole through immunoassay. The structure of the safrole hapten is shown in the specification. The two safrole haptens provided by the invention have spacer arms with proper lengths, and after the safrole haptens are coupled with carrier protein, the haptens can be fully exposed, and recognition of the spacer arms can be avoided as much as possible. The safrole hapten is used for preparing an artificial antigen and an antibody, and the obtained safrole monoclonal antibody is high in titer, strong in specificity and high in affinity. An immunoassay method constructed on the basis of the safrole artificial antigen and antibody has high specificity and sensitivity, the lowest detection limit LOD is 0.09 ng / mL, the half inhibitory concentration IC50 is 2.05 ng / mL, the quantitative detection range is 0.28-14.89 ng / mL, no cross reaction exists on safrole analogues, and rapid qualitative and quantitative detection can be conducted on safrole in a sample.

The invention discloses a novel helper plasmid for producing a recombinant adeno-associated virus as well as a construction method and application of the novel helper plasmid. The novel helper plasmid is constructed by inserting a UL12 element of an I-type herpes simplex virus HSV-1 and an NS2 element of a human bola virus HBoV into a basic pHelper plasmid, the constructed novel helper plasmid UL12-NS2-pHelper can remarkably improve the titer of rAAV produced by HEK293 cells, the proportion of solid rAAV is increased, immunoreaction and toxicity caused by empty capsid can be reduced, and the helper plasmid can be used for preparing the rAAV. The treatment dosage is reduced, and the curative effect and safety are improved.

The invention discloses an RSV antigen, nucleic acid, an expression element, a pharmaceutical composition and application thereof. The RSV antigen is characterized by comprising mutations A102C and S362C on the basis of SEQ ID NO: 1. The RSV antigen has stronger immunogenicity than RSV in the prior art, can obtain higher neutralizing antibody titer, and has higher protective efficacy.

The invention provides an avian adenovirus D11 type tandem multi-epitope vaccine, and belongs to the technical field of veterinary vaccines. According to the invention, an amino acid sequence of fiber protein of the fowl adenovirus D11 type is analyzed, 10 potential B cell epitopes are screened out, 10 antigen epitopes are artificially synthesized to prepare the vaccine, and six antigen epitopes with high neutralizing antibody titer are screened out by immunizing chicken. Flexible peptides are designed among the screened six antigen epitopes for connection, and a series multi-epitope antigen is designed. The oil emulsion vaccine is prepared by expressing tandem multi-epitope antigen protein through recombinant escherichia coli, purifying through a nickel column, and emulsifying with a mineral oil adjuvant. All test chickens immunized by the series multi-epitope vaccine in an over-dose manner have no abnormities in spirit, ingestion and water drinking, injection parts have no red and swollen reactions, and the vaccine is good in safety. The series multi-epitope vaccine has a good immune effect, can enable the immunized chicken to generate a neutralizing antibody to achieve challenge protection, and can block the detoxification of the challenge chicken.

A chimpanzee adenovirus vector from newly discovered and isolated chimpanzee adenovirus with unique HVR sequences and a method of its construction and application thereof, with higher viral titer, and provides a method for determining its viral titer. The chimpanzee adenovirus circular vector is constructed through a shuttle plasmid, and knocks out E1 and E3 to construct a replication-defective chimpanzee adenovirus vector. The chimpanzee adenovirus vector described in this article has no preexisting antibody in the population, and the knockout of E1 and E3 is safe. At the same time, it is significantly different from human adenovirus type 5 E1 in 293 cells, which can greatly avoid recovery mutation (RCA) and make it safer. The novel coronavirus vaccine has strong stability and does not cause mutations after multiple passages, and it can induce strong humoral immunity and cellular response in mouse models.

The invention relates to the technical field of biological medicines, and discloses a PD-L1 K263 acetylation modified antibody, which is prepared from an immunogen containing a sequence as shown in SEQ ID NO.1. The PD-L1 K263 acetylation modified antibody is a PD-L1 K263 acetylation modified antibody. The invention also discloses a preparation method of the PD-L1 K263 acetylation modified antibody. The preparation method comprises the following steps: designing and synthesizing a polypeptide antigen, preparing an immunogen, immunizing animals, purifying the antibody and evaluating serum titer. The antibody provided by the invention can accurately recognize and combine with the PD-L1 protein subjected to K263 acetylation modification in the breast cancer, provides a specific tool for qualitative and quantitative detection of K263Ac-PD-L1 in the breast cancer, and provides a reliable molecular marker detection means for evaluating the curative effect of anti-PD-1 / PD-L1 immunotherapy; therefore, a biological preparation with specificity and practicability and a technical support are provided for accurate diagnosis, targeted therapy and curative effect monitoring of breast cancer.

The invention discloses a self-assembled ferritin nano antigen particle and application thereof in preparation of a duck hepatitis A vaccine. The VP1 part in the duck hepatitis A virus P1 protein is connected with the N end of a self-assembled ferritin nanoparticle subunit through a connecting sequence to obtain the fusion protein, and the amino acid sequence of the fusion protein is shown as SEQ ID NO.1; in order to improve the expression quantity or expression efficiency of the fusion protein in bombyx mori, a nucleotide sequence of a coding gene of the fusion protein is optimized and modified according to the codon preference of bombyx mori, and an optimized gene sequence with the nucleotide sequence shown as SEQ ID NO.2 is obtained; the fusion protein is subjected to single-site or multi-site mutation, the mutant with obviously improved titer is obtained through screening, and the soluble expression quantity of the mutant is obviously improved. According to the invention, a silkworm or insect cell eukaryotic expression system is used for expressing recombinant protein, and an expression product causes a neutralizing anti-duck hepatitis A virus antibody.

The invention provides a Garlu virus attenuated strain and application thereof, and relates to the field of virology and biological medicine. According to the invention, the screened Garlu virus attenuated strain is a natural attenuated strain derived from a tick sample, can grow in Vero cells, has the titer of more than or equal to 107 TCID50 / mL, does not have clinical pathogenicity to an immunodeficient host, and is safe; after the attenuated strain is used as an immunogen for pre-intervention, infection of a lethal virus strain can be avoided, the survival rate is increased to 100%, adverse effects on growth and life of experimental animals are avoided, particularly, a host can be stimulated to generate humoral immunity and cellular immunity at the same time, and the survival rate of the experimental animals is improved. And moreover, broad-spectrum cross-protection efficacy can be generated on Bandavirus lethal virus strains, and a foundation is laid for improvement of research on Bandavirus live vaccines such as the Colu virus and the like.

The invention belongs to the technical field of biological detection, and particularly relates to a monoclonal antibody 1E12 for specific detection of AAV6 and application of the monoclonal antibody 1E12. According to the monoclonal antibody 1E12 provided by the invention, a heavy chain variable region and a light chain variable region respectively comprise three complementary determining regions (CDR) corresponding to SEQ ID NO.1-3 and SEQ ID NO.4-6. The CDRs endow the antibody with high specificity and affinity to AAV6, the antibody can accurately recognize AAV6 virus without cross reaction with other serotypes, and the detection sensitivity reaches 4 * 10 < 6 > vg / ml level. The antibody is suitable for development of multiple detection tools such as a double-antibody sandwich ELISA kit, a test strip and an antibody chip, especially has excellent performance in a biotin-avidin amplification system, can be used for virus identification, titer determination and clinical dose evaluation of AAV6, and provides an effective means for standardized and high-throughput detection.

Disclosed herein are improved methods for quantifying monoclonal antibody (mAb) titer using Protein A affinity High-Performance Liquid Chromatography (HPLC). The methods address inaccuracies caused by mAb adsorption to sample vial surfaces by incorporating a surfactant into the mobile phase used for sample dilution. This approach enhances the accuracy, linearity, and robustness of the titer assay, making it suitable for process control and quality assessment in biopharmaceutical development and manufacturing. The methods can be applied as a platform approach for various mAb products.

The invention discloses a duck BRS3 polypeptide and a preparation method and application of a polyclonal antibody of the duck BRS3 polypeptide, and belongs to the field of biochemistry and molecular immunology. The amino acid sequence of the duck BRS3 polypeptide is as shown in SEQ ID NO. 3. A segment of polypeptide sequence with the length of 20 aa is screened out in an intracellular region of a duck BRS3 protein sequence, after artificial solid-phase synthesis, the polypeptide sequence is used as an immunizing antigen to immunize New Zealand white rabbits, and the duck BRS3 protein polyclonal antibody with the antiserum titer being 1: 25600 or above is obtained. The rabbit anti-duck BRS3 polyclonal antibody prepared by the invention can be specifically combined with the BRS3 protein in duck tissues, so that the blank in the field of detection and research of the duck BRS3 protein is filled, and a foundation is laid for research of functions of the BRS3 in duck bodies.

The invention provides an anti-glycocholic acid antibody and application thereof, and particularly relates to more than ten positive monoclonal hybridoma cell strains obtained by adopting glycocholic acid antigen immune BALB / C mice and screening. Through performance determination, three cell strains capable of being specifically combined with glycocholic acid are finally obtained. Wherein the H15 antibody is high in titer, good in stability and stable in detection linearity, and can be used for clinical detection of glycocholic acid.

The invention belongs to the technical field of antibody preparation, and particularly relates to a recombinant rabbit monoclonal antibody for specifically recognizing type II grass carp reovirus VP56 protein and application of the recombinant rabbit monoclonal antibody. The amino acid sequence of a light chain variable region of the monoclonal antibody is as shown in SEQ ID NO.3, and the amino acid sequence of a heavy chain variable region of the monoclonal antibody is as shown in SEQ ID NO.1. The recombinant rabbit monoclonal antibody for resisting the II type grass carp reovirus VP56 protein prepared by the invention has relatively strong specificity and titer, can specifically recognize the virus VP56 protein in tissues and cells in a natural state, has high affinity for recognizing and combining the virus VP56 protein, has strong anti-interference capability, and can be used for preparing the recombinant rabbit monoclonal antibody for resisting the II type grass carp reovirus VP56 protein. The method is suitable for establishing a high-specificity, high-sensitivity and high-accuracy type II grass carp reovirus diagnosis technology.

A system for measuring an antibody concentration in a sample includes a polarizer holder holding a first detection polarizer and a second detection polarizer, the first detection polarizer restricting fluorescence emitted from within a container to pass in a first direction. The second detection polarizer restricts fluorescence emitted from within the container to pass in a second direction. The second direction is perpendicular to the first direction. The system includes a detector for measuring fluorescence emitted in a first direction and fluorescence emitted in a second direction. The system rotates the polarizer holder in an alternating direction about an axis of rotation such that the first detection polarizer and the second detection polarizer are alternately placed in an optical path of fluorescence emitted from within the container.

The present application belongs to the technical field of antibody preparation, and belongs to a human CHI3L1 monoclonal antibody 1D7, a recombinant carrier, a recombinant plasmid and a method and application. The present application provides a monoclonal antibody 1D7 capable of specifically recognizing CHI3L1, wherein the monoclonal antibody 1D7 comprises a heavy chain and a light chain; a variable region of the heavy chain comprises three heavy chain complementarity determining regions, and the amino acid sequences of the three heavy chain complementarity determining regions are shown as SEQ ID NO. 1-SEQ ID NO. 3 or SEQ ID NO. 11-SEQ ID NO. 13; and a light chain variable region of the monoclonal antibody 1D7 comprises three light chain complementarity determining regions, and the amino acid sequences are shown as SEQ ID NO. 4-SEQ ID NO. 6. The monoclonal antibody provided in the present application has good titer, and the expression carrier and the recombinant cell for preparing the monoclonal antibody are easy to store and modify.

This invention provides a peanut allergen peptide, its screening method, and its application. Phage display technology is used to screen for conformational epitopes of Ara h5 and Ara h8 proteins. Polyclonal IgE and IgG antibodies against the target proteins are prepared by immunizing BALB / c mice with Ara h5 and Ara h8 proteins as antigens. ELISA and dotted immunoblotting detection revealed that the titers of polyclonal IgG and IgE against Ara h5 and Ara h8 proteins were 1:64000 and 1:320, respectively, and the antibodies exhibited specificity. Using the antibodies as targets, phage display technology screened the conformational epitope sequences of Ara h5 protein as WETIYSR and FHWWYLK. The conformational epitopes of Ara h8 protein were FPYMKFV, FPYMKFR, SMFARID, and SFHWWLF.

The invention discloses a feline calicivirus VP1 recombinant protein and application thereof. The amino acid sequence of the feline calicivirus VP1 recombinant protein is shown as SEQ ID No.1 in a sequence table. The neutralizing titers of the feline calicivirus positive serum prepared by adopting the recombinant protein as an antigen and different gene groups are all up to 1: 4096 times or above, the requirements of ELISA and IFA tests can be met, the feline calicivirus positive serum obtained after immunization of the prepared recombinant protein is good in purity, free of bacteria, free of mycoplasma and exogenous virus pollution, high in specificity and good in clinical application prospect. And the strain can react with strains of different evolution groups well, and has good broad spectrum. Positive serum prepared from the recombinant protein prepared by the invention can be used for quality control of different gene group cat calicivirus vaccines, such as specificity test, exogenous virus test, diagnostic detection and the like.