70 results about "Filamentous bacteriophage" patented technology

A strategy for immunizing against amyloid plaques using display technology. The strategy includes methods, agents, and pharmaceutical compositions for vaccination against plaque forming diseases (e.g. Alzheimer's disease) which rely upon presentation of an antigen or epitope on a display vehicle. The strategy further includes methods, agents, and pharmaceutical compositions for vaccination against plaque forming diseases (e.g. Alzheimer's disease) which rely upon presentation of an antibody, or an active portion thereof, on a display vehicle. Whether antigens or antibodies are employed, disaggregation of plaques results from the immunization.

The present invention describes methods for producing antibody libraries, and particularly for increasing antibody library diversity by inducing mutagenesis within the CDR regions of immunoglobulin heavy or light chains that are displayed on the surface of filamentous phage particles comprising the library. The invention also describes oligonucleotides useful for increasing the library diversity, and universal light chains useful in the library production methods.

A method for selecting novel proteins such as growth hormone and antibody fragment variants having altered binding properties for their respective receptor molecules is provided. The method comprises fusing a gene encoding a protein of interest to the carboxy terminal domain of the gene III coat protein of the filamentous phage M13. The gene fusion is mutated to form a library of structurally related fusion proteins that are expressed in low quantity on the surface of a phagemid particle. Biological selection and screening are employed to identify novel ligands useful as drug candidates. Disclosed are preferred phagemid expression vectors and selected human growth hormone variants.

The present invention refers to a method that allows the use of filamentous bacteriophages to detect the presence of molecules of interest in biological samples. It consists of a series of combined operations, which are drawn up and defined according to the characteristics of the phages employed. These have, exposed on the surfaces of the capsid, at least one molecule, generally but not exclusively of proteic nature, capable of binding at least one molecule of interest present in the biological sample. Detection of the presence of the molecule takes place, according to the method of the invention, using the association between the molecule exposed on the surfaces of the phage and the genome of the phage itself. The ability to form specific complexes typical of the molecule exposed on the capsid enables formation of phage-molecule of interest complexes, which can be detected by means of amplification of known sequences in the phage DNA. The method according to the invention is extremely sensitive and can be used in particular for diagnostic and prognostic purposes.

The present invention relates to a filamentous phage display method wherein the polypeptides of interest displayed on the phage particle are cotranslationally translocated across the cytoplasmic membrane of Gram-negative bacteria based on the signal recognition particle pathway. This method is particularly suitable for polypeptides, which are known to be difficult to display on phages, and for proteins of cDNA libraries and other combinatorial libraries, in particular when derived from very fast folding, stable protein scaffolds. The invention further relates to phage or phagemid vectors useful in the method comprising a gene construct coding for a fusion polypeptide comprising the polypeptide to be displayed on the phage particle and an N-terminal signal sequence promoting cotranslational translocation.

Filamentous bacteriophage which does not display an antibody or a non-filamentous bacteriophage antigen on its surface is used to inhibit or treat brain inflammation associated with amyloid deposits and / or involving activated microglia, to inhibit the formation of amyloid deposits, and to disaggregate pre-formed amyloid deposits.

The present invention relates to the use of a filamentous agent other than a filamentous bacteriophage to disaggregate aggregated proteins in plaque or to treat a patient suffering from or susceptible to a disease characterized by the presence of plaque.

[Problems] To provide a phage display vector which can be fused in the inside of pIII and a phage display method using the vector.[Means for Solving Problems] Disclosed is a phage display method which is characterized by using a mutant pIII protein having an amino acid residue inserted between a proline residue at position 11 and a histidine residue at position 12 in an M13 phage pIII protein as depicted in SEQ ID NO:1. The method enables to produce a random peptide with high efficiency and to provide a novel source in peptide conformation.

Described herein is a humanized antibody to vascular endothelial growth factor (VEGF). Also described herein is a method for rapidly producing and identifying framework mutations which improve the binding of humanized antibodies to their cognate antigens. In a preferred embodiment, non-human CDRs are grafted onto a human V1 kappa I-V HIII framework. Random mutagenesis of a small set of critical framework residues is also performed followed by monovalent display of the resultant library of antibody molecules on the surface of filamentous phage. The optimal framework sequences are then identified by affinity-based selection. Optionally, the selected antibodies can be further mutated so as to replace vernier residues which sit at the VL-VH interface by residues which match the non-human parent antibody. The methods described herein can be applied to any non-human antibody. Accordingly, humanized antibodies are provided.

The present invention relates to a filamentous phage display method wherein the polypeptides of interest displayed on the phage particle are cotranslationally translocated across the cytoplasmic membrane of Gram-negative bacteria based on the signal recognition particle pathway. This method is particularly suitable for polypeptides, which are known to be difficult to display on phages, and for proteins of cDNA libraries and other combinatorial libraries, in particular when derived from very fast folding, stable protein scaffolds. The invention further relates to phage or phagemid vectors useful in the method comprising a gene construct coding for a fusion polypeptide comprising the polypeptide to be displayed on the phage particle and an N-terminal signal sequence promoting cotranslational translocation.

Provided are: an agent for preventing bacterial wilt disease, which agent can prevent the development of bacterial wilt disease caused by various different bacterial wilt disease strains, that is, the development of bacterial wilt disease in various different plant varieties; and a method for preventing bacterial wilt disease utilizing the agent for preventing bacterial wilt disease. The agent for preventing bacterial wilt disease comprises as an active ingredient a wilt bacterium (Ralstonia solanacearum) infected with the φRSM1-type filamentous phage and / or the φRSM3-type filamentous phage. The method for preventing bacterial wilt disease comprises the step of inoculating the agent for preventing bacterial wilt disease to a plant. The plant is preferably any one of tomato, potato, green pepper, eggplant, tobacco, capsicum, Japanese basil, Japanese radish, strawberry, banana, marguerite, chrysanthemum and sunflower.

Filamentous bacteriophage which does not display an antibody or a non-filamentous bacteriophage antigen on its surface is used to inhibit or treat brain inflammation associated with amyloid deposits and / or involving activated microglia, to inhibit the formation of amyloid deposits, and to disaggregate pre-formed amyloid deposits.

The present invention is directed to an immunizing composition containing an antigenic product such as a multiple antigen peptide system (MAPS) or a filamentous bacteriophage displaying an AssPP epitope spanning the ss-secretase cleavage site of AssPP and a method for inducing an immune response against the ss-secretase cleavage site of AssPP using this immunizing composition. The present invention is also directed to antibodies against the ss-secretase cleavage site of AssPP and their use in a method for inhibiting the formation of amyloid ss.

The invention describes the display of exogenous polypeptides on filamentous phage using a fusion between the exogenous polypeptide and phage pVII or pIX proteins. In particular, phage particles and phagemid vectors are described for expression and display of heterodimeric proteins such as antibody Fv heterodimers in combinatorial libraries, and uses thereof.

A composition of matter comprising a plurality of procaryotic cells containing diverse combinations of first and second DNA sequences encoding first and second polypeptides which form a heteromeric receptor exhibiting binding activity toward a preselected molecule, said heteromeric receptors being expressed on the surface of filamentous bacteriophage.

The present invention provides novel technologies for producing and screening fusion proteins on the surface of filamentous phage. In particular, a single vector can be used for generating cell and phage libraries containing a given series of protein sequences fused to either one or other of two phage coat proteins. This approach simplifies and improves the efficiency of the subsequent phage display-based selection of protein-binding molecules having therapeutic or diagnostic utility, such as antibodies, peptides, or epitope-binding regions.

Filamentous bacteriophages are particularly efficient for the expression and display of combinatorial random peptides. Two phage proteins are often employed for peptide display: the infectivity protein, pIII and the major coat protein, pVIII. The use of pVIII typically requires the expression of two pVIII genes: the wild type and the recombinant pVIII genes to generate mosaic phages. “Type 88” vectors contain two pVIII genes in one phage genome. A novel “type 88” expression vector has been rationally designed and constructed, which can be used to express recombinant peptides as pVIII chimeric proteins in mosaic bacteriophages. This vector is not only genetically stable but also of high copy number and produces high titers of recombinant phages.

Petroleum reservoir souring caused by microbially induced production of hydrogen sulphide and other sulphur compounds and the attendant corrosion are remediated by isolating bacteriophage specific for the problematic bacteria (target bacteria) and adding an effective amount of such bacteriophage to water introduced into or resident in the reservoir to kill at least some of the target bacteria. Suitable virulent bacteriophage may be indigenous in the water or located in surrounding areas or taken from a known banked stock. Means of concentrating solutions of bacteriophage are also disclosed.

The invention disclsoes a phage vector for dual-epitope display and a construction method thereof. The phage vector for dual-epitope display is a filobactivirus-originated annular vector used for displaying coding gene of pIII protein and pVIII protein of exogenous peptides. By integrating a phage pIII display system and a pVIII display system for the first time, a phage pIII and pVIII dual-epitope display system is formed. Different exogenous peptides can be displayed on pIII protein and pVIII protein of a same phage. Therefore, types of the phage display system are enriched, and new tools and methods are provided for biological and medical application of the system.

The invention discloses a preparation method of a human antinuclear antibody, comprising the following steps: collecting single nuclear cells of peripheral blood of a patient with the autoimmune disease, extracting the total RNA (Ribonucleic Acid), and carrying out reverse transcription to obtain a cDNA (Complementary Deoxyribonucleic Acid) library; amplifying a light chain k,1 gene and an immunoglobulin molecule heavy chain Fd gene by taking the acquired cDNA library as a template through a PCR (Polymerase Chain Reaction) method; cloning the light chain k,1 gene into a pComb3Hss carrier to construct a light chain library; loading the heavy chain Fd gene into a carrier to construct and finish a combinatorial library; transforming the obtained recombinant plasmid into escherichia coli XL1-Blue, infecting by using a helper phage M12KO7, and expressing the random combinatorial library on the surface of a filamentous phage to finish phage surface display; and purifying the Fab segment of the human antinuclear antibody by utilizing affinity chromatography. By using the preparation method, the defects that the random combinatorial antibody library has strong randomness, the screening workload is large and a specific antibody is not easy to obtain are overcome, and the specific antibody can be directly screened from a phage antibody library; and in addition, the method is simple and feasible, and the experimental period is shortened.

A method of controlling filamentous bacteria responsible for foaming and bulking in wastewater systems with virulent bacteriophage. The method includes, optionally, identification of problematic filamentous bacteria and matching virulent bacteriophage, use of bacteriophage from phage libraries and concentration of filamentous bacteria and bacteriophage from the wastewater to be treated.

The invention relates to the fields of nanomaterials, catalysis and analytical chemistry, in particular to a preparation method for synthesizing a manganese dioxide nanowire on the basis of using filamentous phage as a biological template and the application of the manganese dioxide nanowire in catalysis aspect. The method comprises the following steps: mixing the filamentous phage with manganous ions by using inherent nanostructure characteristics of the filamentous phage and properties of capsid protein of the filamentous phage; adding sodium hydroxide and carrying out normal temperature reaction to generate manganese dioxide on the surface of the filamentous phage, namely obtaining the manganese dioxide nanowire with the diameter of 10 to 50nm. The material has the biomimetic catalytic characteristic and electrochemical catalysis characteristic, so that the material has a broad application prospect in the fields of analytical chemistry, capacitors and catalysis. According to the method, a natural nanobiological structure is used as a template; the method has the advantages of simple preparation process, mild and environment-friendly reaction conditions and easily-controlled nanostructure.

The present invention discloses a bifunctional phage and uses thereof. According to the present invention, a WR polypeptide capable of specifically recognizing vascular endothelial growth factor (VEGF) is successfully obtained through phage biopanning, and the WR polypeptide and a tumor-targeting recognition peptide are simultaneously displayed on filamentous phage to form a bifunctional phage, wherein the phage can specifically recognize tumor and can also block the entering of the VEGF secreted by tumor cells into vascular endothelial cells around tumor so as to inhibit the formation of new blood vessels around the tumor; with the technology, the tumor cells cannot proliferate due to insufficient nutrients and cannot successfully pass through the capillaries, such that the tumor metastasis cannot be achieved; and the bifunctional phage overcomes the disadvantages of deficiency in targeting, high cost, complex preparation and the like of the traditional targeting drugs.