384 results about "Phage display" patented technology

The invention provides a method for selecting, from a repertoire of polypeptides, a population of functional polypeptides which bind a target ligand in a first binding site and a generic ligand in a second binding site, which generic ligand is capable of binding functional members of the repertoire regardless of target ligand specificity, comprising the steps of: a) contacting the repertoire with the generic ligand and selecting functional polypeptides bound thereto; and b) contacting the selected functional polypeptides with the target ligand and selecting a population of polypeptides which bind to the target ligand. The invention accordingly provides a method by which a polypeptide repertoire is preselected, according to functionality as determined by the ability to bind the generic ligand, and the subset of polypeptides obtained as a result of such preselection is then employed for further selection according to the ability to bind the target ligand.

Anti-VEGF antibodies and variants thereof, including those having high affinity for binding to VEGF, are disclosed. Also provided are methods of using phage display technology with naïve libraries to generate and select the anti-VEGF antibodies with desired binding and other biological activities. Further contemplated are uses of the antibodies in research, diagnostic and therapeutic applications.

The present invention describes peptides capable of specifically binding to preselected micromolecules or to their natural receptor. The preselected molecules include but are not limited to drugs, vitamins, neuromediators and steroid hormones. Methods of using the phage display libraries to identify peptide compositions in preselected binding interactions are also disclosed. The retrieved peptides mimicking a natural receptor binding site to preselected molecules are used as is or as ligands to re-screen the same or different libraries to find and / or derive new receptor ligands, or are used to elicit the production of antibodies capable of binding to the natural receptor. The two categories of effector molecules (peptides or antibodies) may find diagnostic, therapeutic or prophylactic uses. The peptides directly derived from the phage display libraries may be used as drug detectors or antidotes. The others may be used to identify, target, activate or neutralize the receptor for the preselected micromolecules, the receptor being known or unknown.

The invention relates to posttranslational modification of phage-displayed polypeptides. These displayed polypeptides comprise at least one unnatural amino acid, e.g., an aryl-azide amino acid such asp-azido-L-phenylalanine, or an alkynyl-amino acid such as para-propargyloxyphenylalanine, which are incorporated into the phage-displayed fusion polypeptide at a selected position by using an in vivo orthogonal translation system comprising a suitable orthogonal aminoacyl-tRNA synthetase and a suitable orthogonal tRNA species. These unnatural amino acids advantageously provide targets for posttranslational modifications such as azide-alkyne [3+2]cycloaddition reactions and Staudinger modifications.

Anti-VEGF antibodies and variants thereof, including those having high affinity for binding to VEGF, are disclosed. Also provided are methods of using phage display technology with naïve libraries to generate and select the anti-VEGF antibodies with desired binding and other biological activities. Further contemplated are uses of the antibodies in research, diagnostic and therapeutic applications.

The present invention relates to a method for adjusting the affinity of a polypeptide to a target molecule by a combination of steps, including: (1) the identification of aspartyl residues which are prone to isomerization; (2) the substitution of alternative residues and screening the resulting mutants for affinity against the target molecule. In a preferred embodiment, the method of subtituting residues is affinity maturation with phage display (AMPD). In a further preferred embodiment the polypeptide is an antibody and the target molecule is an antigen. In a further preferred embodiment, the antibody is anti-IgE and the target molecule is IgE. In another embodiment, the invention relates to an anti-IgE antibody having improved affinity to IgE.

The invention overcomes the deficiencies of the prior art by providing a rapid approach for isolating binding proteins capable of binding small molecules and peptides. In the technique, libraries of candidate binding proteins, such as antibody sequences, are expressed in the periplasm of gram negative bacteria and mixed with a labeled ligand. In clones expressing recombinant polypeptides with affinity for the ligand, the concentration of the labeled ligand bound to the binding protein is increased and allows the cells to be isolated from the rest of the library. Where fluorescent labeling of the target ligand is used, cells may be isolated by fluorescence activated cell sorting (FACS). The approach is more rapid than prior art methods and avoids problems associated with the outer surface-expression of ligand fusion proteins employed with phage display.

Disclosed herein are humanized antibodies in which human germline residues are introduces to the complementarity determining regions (CDRs) of a non-human donor antibody. Also described herein are libraries of antibody variable domains (e.g., phage-display libraries) and methods for screening for humanized antibodies.

Antibodies are disclosed which specifically bind to native PrPSc in situ. Preferred antibodies bind only to the native PrPSc of a particular species e.g., human, cow, sheep, pig, etc. Particularly preferred antibodies bind specifically to a particular isoform of human PrPSc. Preferred antibodies of the invention are (1) produced by phage display methodology, (2) bind specifically to native PrPSc, (3) neutralizes the infectivity of prions, (4) bind to PrPSc in situ and (5) bind 50% or more of PrPSc in a liquid flowable sample. Antibodies of the invention can be bound to a substrate and used to assay a sample (which has any PrPSc denatured via proteinase K) for the presence of PrPSc of a specific species which PrPSc is associated with disease. Antibodies which specifically bind to human PrPSc can be labeled and injected carrying out an in vivo diagnostic test to determine if the human is infected with prions associated with disease. The antibodies are preferably produced using phage display technology wherein the genetic material in the phage expressing the antibody is obtained from a mammal with an ablated endogenous PrP protein gene and an endogenous chimeric PrP gene which mammal had been inoculated with PrPSc to induce antibody production.

Transdermal delivery peptides for the treatment of skin diseases and / or facilitation or enhancement of transdermal delivery of pharmaceutically active agents are provided. Compositions comprising the transdermal delivery peptides and methods of therapeutic use, including the improvement of transdermal delivery of drugs or other pharmaceutically active agents, are also disclosed. Nucleic acids, expression vectors, and methods of their use, which encode the transdermal delivery peptides are disclosed. Methods are also provided for in vivo phage display for identifying further peptides with enhanced transdermal delivery capability.

A pharmaceutical composition for treating allergy is described. The composition comprises as an active ingredient a recombinant polyclonal antibody or a mixture of different monoclonal antibodies capable of reacting with or binding to an allergen together with one or more pharmaceutically acceptable excipients. The composition may be used topically as a solution, dispersion, powder, or in the form of microspheres. The polyclonal antibody is preferably a recombinant polyclonal antibody produced by phage display technology. The pairing of specific immunoglobulin variable region light chain and heavy chain maintained from the original polyclonal immune response or selected by panning using the allergen in question is preferably maintained by bulk transfer of the pairs into an expression vector.

A phage-displayed library of llama single heavy domain antibodies (sdAbs) was enriched for species that selectively bind to and are internalized by human cerebromicrovascular endothelial cells (HCEC). From the enriched library, two sdAbs were selected, sequenced, subcloned, and expressed as fusion proteins with c-myc-His5 tags. Similarly as phage-displayed sdAbs, these soluble tagged sdAbs were shown to selectively bind to HCEC and to transmigrate across in vitro human blood-brain barrier (BBB) model. In contrast to an unrelated llama sdAb, these sdAbs were also detected in the brain after i.v. injection into mice. These small (˜13 kDa) antibody fragments have essential characteristics of brain-specific delivery vectors and can be used to facilitate drug transport across the BBB.