412 results about "Insect cell" patented technology

The current invention provides methods to silence insect genes by using unpackaged dsRNA or siRNA, in one embodiment such dsRNA or siRNA is present in plant vascular tissue, preferably phloem, more particularly phloem sap, and the insect is a plant sap-sucking insect. Also provided are DNA sequences which when transcribed yield a double-stranded RNA molecule capable of reducing the expression of an essential gene of a plant sap-sucking insect, methods of using such DNA sequences and plants or plant cells transformed with such DNA sequences. Also provided is the use of cationic oligopeptides that facilitate the entry of dsRNA or siRNA molecules in insect cells, such as plant sap-sucking insect cells.

The present invention relates to the production of adeno-associated viral vectors in insect cells. The insect cells therefore comprise a first nucleotide sequence encoding the adeno-associated virus (AAV) capsid proteins, whereby the initiation codon for translation of the AAV VP1 capsid protein is a non-ATG, suboptimal initiation codon. The insect cell further comprises a second nucleotide sequence comprising at least one AAV inverted terminal repeat (ITR) nucleotide sequence; a third nucleotide sequence comprising a Rep52 or a Rep40 coding sequence operably linked to expression control sequences for expression in an insect cell; and, a fourth nucleotide sequence comprising a Rep78 or a Rep68 coding sequence operably linked to expression control sequences for expression in an insect cell. The invention further relates to adeno-associated viral vectors with an altered ratio of the viral capsid proteins that provides improved infectivity of the viral particles.

Recombinant influenza virus proteins, including influenza capsomers, subviral particles, virus-like particles (VLP), VLP complexes, and / or any portions of thereof, are provided as a vaccine for influenza viruses. The invention is based on the combination of two vaccine technologies: (1) intrinsically safe recombinant vaccine technology, and (2) highly immunogenic, self-assembled protein macromolecules embedded in plasma membranes and comprised of multiple copies of influenza virus structural proteins exhibiting neutralizing epitopes in native conformations. More specifically, this invention relates to the design and production of functional homotypic and heterotypic recombinant influenza virus-like particles (VLPs) comprised of recombinant structural proteins of human influenza virus type A / Sydney / 5 / 94 (H3N2) and / or avian influenza virus type A / Hong Kong / 1073 / 99 (H9N2) in baculovirus-infected insect cells and their application as a vaccine in the prevention of influenza infections and as a laboratory reagent for virus structural studies and clinical diagnostics.

The invention discloses an insect bioreactor capable of expressing multiple exogenous genes, and a construction method and application thereof. The construction method comprises the following steps: (1) introducing multicopy high-efficiency bacteria DNA (deoxyribonucleic acid) replication initiator into chitinase and cysteine proteinase genes of a baculovirus genome to obtain a baculovirus shuttle plasmid; (2) replacing virus duplicated essential gene downstream the polyhedrosis gene of the baculovirus shuttle plasmid with antibiotic gene to obtain a baculovirus plasmid DNA; and (3) replacingother virus duplicated and infected nonessential genes in the baculovirus shuttle plasmid with reverse selection marker gene to obtain the insect bioreactor. The antibiotic gene or reverse selection marker gene in the insect bioreactor which is constructed by replacing the exogenous target genes can express multiple exogenous genes in a host insect or insect cell. The insect bioreactor disclosed by the invention can efficiently expressing one or more exogenous genes in an insect body at the same time, and can produce massive recombinant proteins at low cost.

The present teachings disclose nucleic acid cassettes for expressing in an insect cell a plurality of polypeptides encoded by a gene comprising overlapping open reading frames (ORFs). A cassette comprises, in 5′ to 3′ order, a) a first insect cell-operable promoter, b) a 5′ portion of a gene comprising a first ORF of the gene, c) an intron comprising a second insect cell-operable promoter, and d) a 3′ portion of the gene comprising at least one additional ORF. Vectors and insect cells comprising the cassettes are also disclosed, as well as methods for production of recombinant adeno-associated virus in insect cells using the cassettes.

Chimeric virus-like particles that exhibit conformational antigenic epitopes capable of eliciting neutralizing antibodies are disclosed herein. The chimeric virus-like particles of the invention comprise a recombinant viral capsid protein that encapsulates a recombinant viral protein during self-assembly into a chimeric virus-like particle, wherein the chimeric virus-like particle exhibits confirmational antigenic epitopes capable of eliciting neutralizing antibodies. Pharmaceutical compositions, vaccines, and diagnostic test kits containing the chimeric virus-particles are also provided.

The present invention relates nucleic acid constructs for the production of recombinant parvoviral (e.g. adeno-associated viral) vectors in insect cells, to insect cells comprising such constructs and to methods wherein the cells are used to produce recombinant parvoviral virions. The insect cells preferably comprise a first nucleotide sequence encoding the parvoviral rep proteins whereby the initiation codon for translation of the parvoviral Rep78 protein is a suboptimal initiation codon that effects partial exon skipping upon expression in insect cells. The insect cell further comprises a second nucleotide sequence comprising at least one parvoviral (AAV) inverted terminal repeat (ITR) nucleotide sequence and a third nucleotide sequence comprising a sequences coding for the parvoviral capsid proteins.

The present invention relates to production of proteins in insect cells whereby repeated coding sequences are used in baculoviral vectors. In particular the invention relates to the production of parvoviral vectors that may be used in gene therapy and to improvements in expression of the viral rep proteins that increase the productivity of parvoviral vectors.

The present invention relates to the improved production of recombinant parvoviral virions in insect cells. In particular, the invention relates to an improved process for the production of recombinant parvoviral virions in insect cells, wherein the full / empty parvoviral virion ratio is increased. The invention also relates to the production of parvoviral vectors that may be used in gene therapy and to improvements in expression of the viral Rep proteins that increase the productivity of parvoviral vectors.

Codon optimized polynucleotides for optimal expression of recombinant proteins in eukaryotic cells are provided. The codon optimized polynucleotides encode a viral capsid protein that self assembles into a virus-like particle. The virus-like particle is expressed extracellularly and exhibits conformational antigenic epitopes capable of raising neutralizing antibodies. Pharmaceutical compositions, vaccines, and diagnostic test kits containing the gene products of the codon-optimized polynucleotides are also provided.

Production of clinical grade gene therapy vectors for human trials remains a major hurdle in advancing cures for a number of otherwise incurable diseases. Disclosed herein are systems based on a stably trans formed insect cell lines harboring helper genes required for vector production. Specifically exemplified are system embodiments that take advantage of DNA regulatory elements from two unrelated viruses—AcMNPV and AA V2. System embodiments utilize rep and / or cap genes either stably transfected in cell lines or which are introduced into cells as an expression cassette in a vector. Rep and cap genes that are designed to remain silent until the cell is infected with a viral vector. Infection with viral initiates rescue / amplification of integrated AAV helper genes resulting in dramatic induction of the expression and assembly of rAAV. The arrangement of this specific embodiment provides high levels of Rep and Cap proteins in every cell thus improving rAAV yields by 10-fold. The described vectors are modular in design and may be utilized for the production of other multiprotein complexes.

The invention provides influenza proteins, including subunit proteins and immunogenic compositions that can be utilized, with or without adjuvants, as vaccines to protect against influenza infection in animal models and humans. The recombinant proteins are expressed from transformed insect cells that contain integrated copies of the appropriate expression cassettes in their genome. The invention uses a Drosophila melanogaster expression system to provide high yields of recombinant subunit proteins with native-like conformation.

The invention provides influenza proteins, including subunit proteins and immunogenic compositions that can be utilized, with or without adjuvants, as vaccines to protect against influenza infection in animal models and humans. The recombinant proteins are expressed from transformed insect cells that contain integrated copies of the appropriate expression cassettes in their genome. The invention uses a Drosophila melanogaster expression system to provide high yields of recombinant subunit proteins with native-like conformation.

The present invention provides a method for altering a B cell mediated pathology in a patient. This method comprises administering a composition comprising at least one and / or two chimeric proteins. Each chimeric protein comprises at least a portion of either the VH or VL region of a immunoglobulin molecule from particular B cells from a patient having a B cell mediated pathology, and an immunoglobulin constant region. The genes encoding VH and / or VL regions and the genes encoding immunoglobulin constant regions are isolated and inserted into an expression vector. The chimeric proteins are produced by introducing the expression vectors into insect cell lines. The chimeric proteins are purified using antibody affinity columns, and then chemically conjugated to an immunogenic carrier, keyhole-limpet hemocyanin (KLH). Since the conjugates comprise chimeric proteins made specifically from particular B cells from a patient having B cell mediated pathology, when it is administered to such a patient, with or without a cytokine, such as granulocyte-macrophage-CSF, or a chemokine, it can induce immune responses to alter such a B cell mediated pathology.

The invention discloses a preparing method of insect sample, which comprises the following steps: fixing living insect, dehydrating through alcohol, replacing, permeating, solidifying or polymerizing to obtain the insect sample, fitting for studying microscopic structure and super-microscopic structure of insect cell.

The present invention relates to nucleic acid molecules, polypeptides encoded by the same, antibodies directed thereto and a method of preparing such polypeptides including: (a) inserting an isolated DNA molecule coding for a polypeptide which is immunoreactive with a 66 kDa polypeptide derived from Borrelia garinii IP90 into an expression vector; (b) transforming a host organism or cell with the vector; (c) culturing the transformed host cell under suitable conditions; and (d) harvesting the polypeptide. The isolated DNA molecule is preferably at least 10 nucleotides in length, and the method may optionally include subjecting the polypeptide to post-translational modification. The host cell can be a bacterium, a yeast, a protozoan, or a cell derived from a multicellular organism such as a fungus, an insect cell, a plant cell, or a mammalian cell.

The present invention relates to nucleic acid molecules, polypeptides encoded by the same, antibodies directed thereto and a method of preparing such polypeptides including: (a) inserting an isolated DNA molecule coding for a polypeptide which is immunoreactive with a 66 kDa polypeptide derived from Borrelia garinii IP90 into an expression vector; (b) transforming a host organism or cell with the vector; (c) culturing the transformed host cell under suitable conditions; and (d) harvesting the polypeptide. The isolated DNA molecule is preferably at least 10 nucleotides in length, and the method may optionally include subjecting the polypeptide to post-translational modification. The host cell can be a bacterium, a yeast, a protozoan, or a cell derived from a multicellular organism such as a fungus, an insect cell, a plant cell, or a mammalian cell.