20 results about "Wild type virus" patented technology

This invention belongs to the field of genetic engineering. By introducing a TC tag between amino acids 199 and 200 of the wild-type bluetongue virus non-structural protein NS2, a recombinant virus was rescued. Analysis of viral plaques and growth curves revealed that the recombinant virus formed plaques of similar size to the wild-type virus, and their growth curves showed no significant difference. Immunofluorescence and FlasH-EDT2 staining of NS2 showed that the fluorescence of NS2 labeled with anti-NS2 antibody overlapped with that labeled with FlasH-EDT2. Three-dimensional imaging of FlasH-EDT2-labeled NS2 revealed that the viral inclusion bodies exhibited fluorescence around the periphery but no fluorescence inside, displaying an overall "core-shell" hierarchical structure. This recombinant bluetongue virus can be used for tracing and localizing NS2 protein and viral inclusion bodies in living cells, and can also be applied to BTV neutralization assays, antiviral drug screening, and other related research.

The present disclosure relates to a viral vector having an exogenous RNA segment having a hairpin-like structure, for example, having two or more base pairing regions separated by one or more non-base pairing regions. The exogenous RNA segment may have a secondary structure, minimum free energy, average position entropy, or other properties within a specified range, or have a value similar to one or more hairpin-like structures of a reference wild-type virus. In some examples, the viral vector is a live attenuated vaccine. In some examples, the viral vectors down-regulate a susceptibility gene in a host plant.

The present invention is related to method of preparing a gain-of-function mutation in poxvirus, like buffalopox virus (BPXV) by long-term propagating it in the presence of methyltransferase inhibitor like 3-Deazaneplanocin A (DZNep), which results in generation of viral 2'O-MTAse (VP39) mutant with a single point mutation (M236I). The resultant mutant has the following characteristics: (a) M236I mutation of 2'O-MTAse increases the cap-1 markings on viral mRNA; (b) The 2'O-MTAse mutant virus had hyperactive 2'O-MTAse and exhibited enhanced stability and translational efficiency of its mRNA; (c) The capping (cap1) performed by the mutant viral 2'O-MTAse (VP39) results in higher viral protein production, as compared to the wild type VP39 and (d) Mutant virus replicated at higher viral titer than the wild-type virus.

This invention discloses an attenuated chikungunya virus expressing a nanoluciferase gene, the nucleotide sequence of which is shown in SEQ ID NO:1. It is constructed by attenuating the virulence of the chikungunya virus LR2006-OPY1 strain by deleting 61 amino acids from positions 323 to 383 of the nsP3 protein and inserting a nanoluciferase gene after position 490 of the nsP3 protein. This virus model maintains similar growth characteristics to the wild-type virus but with significantly improved safety. Viral replication can be monitored in real time by detecting luciferase activity, making it suitable for drug screening at both cellular and animal levels. This provides an efficient and safe technical platform for the development of antiviral drugs against chikungunya virus.

Provided are an oncolytic virus preparation capable of crossing a blood-brain barrier, a preparation method therefor and a use thereof. The oncolytic virus preparation is an oncolytic virus modified by a polypeptide having a function of crossing a blood-brain barrier. The polypeptide having the function of crossing the blood-brain barrier is RVG29-Cys. The oncolytic virus is a genetically engineered oncolytic virus OH2 in which neurotoxic and immunosuppressive genes in a wild-type virus genome are knocked out and an immune-enhancing human granulocyte-macrophage colony stimulating factor gene is inserted. An OH2-PEG-RVG nanosystem is constructed by conjugating NHS-PEG-Mal to OH2, and then coupling a Mal group on NHS-PEG-Mal to a Cys group on RVG29-Cys, thus increasing the aqueous solubility of a drug while facilitating the therapeutic drug crossing of the blood-brain barrier to treat brain tumors, and preventing neutralizing antibodies and macrophages in vivo from neutralizing and phagocytosing the oncolytic virus, thereby prolonging the circulation time in vivo.

The present disclosure belongs to the field of viral vectors, and provides AAV capsid protein variants and applications thereof. The capsid protein variants are obtained by inserting a polypeptide into a wild-type AAV viral capsid protein. The capsid protein variants of the present disclosure can effectively improve the retinal cell infectivity of AAV viruses.

The present disclosure relates to a viral vector suitable for introducing a therapeutic agent, such as a peptide, protein or small RNA, into a host or otherwise treating a host. The vector may include an exogenous RNA segment with a hairpin-like structure or having two or more base-paired regions separated by one or more non-base-paired regions. The exogenous RNA segment may have a secondary structure, minimum free energy, average positional entropy or other attributes within specified ranges, or with values similar to one or more hairpin-like structures of a reference wild type virus. Optionally, the RNA vector may be derived from the reference wild type virus or a relative of the reference wild type virus. In some examples, the vector is capable of capable of systemic and phloem-limited movement and replication within a host plant. In some examples, the reference wild type virus is an umbravirus-like associated RNA.

The invention belongs to the technical field of biology, and particularly discloses a cell line capable of stably expressing an nsP4 gene and application of the cell line in preparation of a replication-deficient chikungunya virus. The inventor uses retrovirus for expressing CHIKV nsP4 to infect hamster kidney cells (hamster kidney cells), after puromycin screening, verification of passage stability of monoclonal cells, protein expression stability, replication-deficient virus titer and the like is carried out, finally, a cell line which can be used for continuous passage of CHIKV replication-deficient viruses and has high titer is obtained, and the preservation number is CCTCC NO: C2025281. The replication-deficient virus CHIKV-delta nsP4 generated by the RNA of the nsP4 gene deleted from the trans-complementary CHIKV of the cell line has good safety, immunogenicity and immune protection efficacy, can effectively resist the challenge infection of wild viruses, and can be used for preparing a safe and effective CHIKV novel vaccine candidate strain.

The invention relates to pharmaceutical product comprising a polynucleotide for use in the prevention or treatment of a SARS-CoV-2 virus infection wherein said SARS-CoV-2 virus is not a Wuhan wild-type SARS-CoV-2 virus. The polynucleotide encodes an attenuated human coronavirus or a fragment thereof, wherein the polynucleotide comprises at least 20 one-to-stop codons, wherein a one-to-stop codon is i) a different but synonymous codon compared to the corresponding codon in a natural human coronavirus genome and ii) differs by one nucleotide from a STOP codon.

The invention discloses a lentiviral vector with efficient transduction capability on T cells and application of the lentiviral vector. The lentiviral vector comprises a nucleic acid sequence for coding recombinant virus envelope glycoprotein, and the recombinant virus envelope glycoprotein has the following structure from the N end to the C end in sequence; wherein the element A is a protein element of wild type virus envelope glycoprotein, the element B is an auxiliary protein element, the auxiliary protein element specifically recognizes cell membrane surface protein, and the element C is a transmembrane structural domain and is a peptide bond or a peptide chain connector. The lentivirus obtained by packaging the lentivirus vector containing the recombinant virus envelope glycoprotein can transduce T lymphocytes with higher efficiency, introduces an exogenous gene into the T lymphocytes, and can be used as a vector in the preparation process of CAR-T cells, so that the production efficiency of the CAR-T cells is improved, and the yield of the CAR-T cells is increased.

The present application relates to an attenuated oncolytic virus strain, an oncolytic virus vaccine and a drug for treating tumors by combining the oncolytic virus vaccine with immune cells. The present application provides a new attenuated oncolytic virus strain by a site-directed mutation of a matrix protein M of a VSV wild-type virus. On the basis of the attenuated oncolytic virus strain, the present application further provides a vaccine that can be used in tumor treatment. On the basis of the vaccine, the present application further provide a drug that can effectively treat multiple kinds of tumors by combining the vaccine with immune cells.

The present invention provides live attenuated vaccines for the prophylactic treatment of Chikungunya virus infections. The vaccines comprise a genetically modified Chikungunya virus that has a reduced replication capacity due to a mutation or deletion in the R5 region of the hypervariable domain of nsP3, a nonstructural protein that interacts with host factors. The inventors have indeed discovered that the R5 region of the hypervariable domain of nsP3, a nonstructural protein that interacts with host factors, is critical for CHIKV replication and pathogenesis. Specifically, the inventors have shown that the R5 region is required for the interaction of nsP3 with FHL1, BIN1 and CD2AP, three host proteins that are involved in the regulation of actin cytoskeleton and membrane trafficking. These host proteins are expressed in muscle and joint tissues, which are the main targets of CHIKV infection and inflammation. By mutating or deleting the R5 region of nsP3, the inventors have generated a genetically modified CHIKV (CHIKV-ΔR5) that has a reduced replication capacity and virulence compared to the WT virus. Moreover, the inventors have demonstrated that CHIKV-ΔR5 is able to elicit a strong neutralizing antibody response and protect mice from lethal challenge with WT virus. The present invention also provides screening methods for identifying test substances that are capable of inhibiting the interaction between nsP3 and FHL1, CD2AP and BIN1, wherein the selected test substances would be suitable for the treatment of CHIKV infections.

The present invention relates to recombinant HVT vectors expressing antigens of avian pathogens and uses thereof. In particular, the present invention provides recombinant herpesvirus comprising and expressing a turkey (HVT) vector of an antigen of an avian pathogen, compositions comprising the recombinant HVT vectors, multivalent vaccines comprising the recombinant HVT vectors and one or more wild-type viruses or recombinant vectors. The present invention also provides methods of vaccinating against multiple avian pathogens and methods of making the recombinant HVT vectors.

The invention provides a recombinant oncolytic adenovirus based on PCV2 functional protein as well as a preparation method and application of the recombinant oncolytic adenovirus, and belongs to the technical field of biological medicines. The genome of the recombinant oncolytic adenovirus based on the PCV2 functional protein provided by the invention comprises a PCV2 Cap gene and / or a PCV2 Rep gene. According to the invention, the Cap and / or Rep genes of PCV2 are / is taken as brand new therapeutic transgenosis, the recombinant oncolytic adenovirus is successfully constructed, and brand new candidate entities and action target bases different from traditional cell factors or tumor suppressor genes are provided for oncolytic virus therapy. According to the invention, the recombinant adenovirus is used as an efficient delivery vector, so that the transduction and expression efficiency of the PCV2 functional gene is greatly improved, and the limitations of low natural infection efficiency and weak replication ability of the PCV2 wild type virus are overcome. The recombinant oncolytic adenovirus, especially the recombinant Rep adenovirus, provided by the invention realizes a multi-mechanism synergistic efficient anti-tumor effect.

The invention belongs to the technical field of biological detection, and relates to a probe primer combination for detecting AdV wild type virus residues and a method and application thereof. According to the invention, two sets of primer probe combinations respectively targeting wild type adenovirus E1A-CR2 and E3 regions are designed, and dPCR is utilized to realize dual-target synchronous detection and signal distinguishing. By calculating the concentrations of linkages of two targets on the same DNA chain, false positive results caused by host cell DNA residues, incomplete E3 region knockout or single region non-specific amplification can be effectively eliminated, so that the specific recognition of the wild type adenovirus is realized. The method is convenient and rapid, can complete detection of AdV wild virus residues in a short time, and does not need expensive instruments and equipment; compared with a PCR (Polymerase Chain Reaction) method (about 1 / 107), the method has the advantages that the sensitivity is improved by 2 orders of magnitude, and the sensitivity can be improved to 0.5 / 109 or above.

This invention belongs to the field of biodetection technology and relates to a method for specifically detecting wild-type virus residues in modified viral products and its application. This invention significantly suppresses non-specific extension into a mutant background by using LNA-modified primers; simultaneously, the SNP-embedded probe design differentiates at the signal level, amplifying the fluorescence signal differences between wild-type and mutant sequences. Finally, the ddPCR platform effectively eliminates PCR inhibitors and background noise from non-specific amplification. These three factors synergistically produce a significant enhancement effect. Taking VSV as an example, the embodiments demonstrate that this method can stably and repeatedly detect wild-type virus with a proportion as low as 1 / (10^7) against a mutant virus background of up to 10^10 copies, achieving a sensitivity at the part-in-ten-millions level. This represents an improvement of at least four orders of magnitude compared to traditional methods, far exceeding the reasonable expectations of those skilled in the art based on conventional technological improvements.

The application discloses a capsid protein mutant capable of improving the whole-eye infection ability of an AAV virus and an application thereof. The inventors have found that the whole-eye infection ability of an AAV virus can be effectively improved by using a specific peptide to replace amino acids at positions 561 to 588 of a wild-type AAV2 virus capsid protein, and the problem of the infection efficiency of AAV2 on eyes is fundamentally solved.

The invention provides a set of novel Single domain VHH antibodies against SARS-CoV-2 (SEQ ID No 1-6) and their use to detect and neutralize the wild type virus.

The invention relates to the technical field of biology, and discloses a mutant of virus envelope glycoprotein, which is characterized in that compared with a protein with an amino acid sequence as shown in SEQ ID NO: 1, the mutant comprises mutation of at least one site in H24, K63, H255 and R370. Compared with wild type virus envelope glycoprotein, the mutant virus envelope glycoprotein provided by the invention has the advantage that the broad-spectrum infection target cell recognition function in virus particles is remarkably reduced. The invention also discloses a virus particle containing the mutant protein. The virus particle has the characteristics of flexible design and efficient target infection of target cells.

The invention provides an in-vivo and in-vitro double visual recombinant mouse poxvirus genome, a recombinant mouse poxvirus strain and application, and belongs to the technical field of gene engineering. The invention provides a recombinant mouse poxvirus genome. The recombinant mouse poxvirus genome comprises a mouse poxvirus genome, a red fluorescent protein gene mKate and a Gaussian luciferase protein gene Gluc, wherein the red fluorescent protein gene mKate and the Gaussian luciferase protein gene Gluc are inserted between the mouse poxvirus genome A11R and the mouse poxvirus genome A12L. According to the invention, the area A of the mouse poxvirus is modified, and the double-reporter gene is inserted between A11R and A12L for the first time, so that the mouse poxvirus-resistant high-throughput drug screening method can be used for anti-orthopoxvirus high-throughput drug screening, the in-vivo effect of the drug can be more intuitively displayed, and the operation is simple and convenient. The recombinant virus obtained by the invention has good hereditary stability, has similar biological characteristics and virulence to a wild type virus, can visualize infection and distribution of the virus in a mouse body, and can be used for in-vitro high-throughput screening of drugs and development of corresponding vaccines.