110 results about "Fusogenic peptide" patented technology

Amphipathic lytic peptides are ideally suited to use in a ligand / cytotoxin combination to specifically inhibit cells that are driven by or are dependent upon a specific ligand interaction; for example, to induce sterility or long-term contraception, or to attack tumor cells, or to selectively lyse virally-infected cells, or to attack lymphocytes responsible for autoimmune diseases. The peptides act directly on cell membranes, and need not be internalized. Administering a combination of gonadotropin-releasing hormone (GnRH) (or a GnRH agonist) and a membrane-active lytic peptide produces long-term contraception or sterilization in animals in vivo. Administering in vivo a combination of a ligand and a membrane-active lytic peptide kills cells with a receptor for the ligand. The compounds are relatively small, and are not antigenic. Lysis of gonadotropes has been observed to be very rapid (on the order of ten minutes.) Lysis of tumor cells is rapid. The two components-the ligand and the lytic peptide-may optionally be administered as a fusion peptide, or they may be administered separately, with the ligand administered slightly before the lytic peptide, to activate cells with receptors for the ligand, and thereby make those cells susceptible to lysis by the lytic peptide. The compounds may be used in gene therapy to treat malignant or non-malignant tumors, and other diseases caused by clones or populations of "normal" host cells bearing specific receptors (such as lymphocytes), because genes encoding a lytic peptide or encoding a lytic peptide / peptide hormone fusion may readily be inserted into hematopoietic stem cells or myeloid precursor cells.

An acid-cleavable peptide linker comprising aspartic acid and proline residues is disclosed. The acid-cleavable peptide linker provides an altered sensitivity to acid-hydrolytic release of peptides of interest from fusion peptides of the formula PEP1-L-PEP2. The inventive linker, L, is described in various embodiments, each of which provides substantially more rapid acid-release of peptides of interest than does a single aspartic acid-proline pair. In an additional aspect, a method of increasing the stability of an acid cleavable linkage to acid hydrolysis is also provided.

The present invention is directed to protocells for specific targeting of hepatocellular and other cancer cells which comprise a nanoporous silica core with a supported lipid bilayer; at least one agent which facilitates cancer cell death (such as a traditional small molecule, a macromolecular cargo (e.g. siRNA or a protein toxin such as ricin toxin A-chain or diphtheria toxin A-chain) and / or a histone-packaged plasmid DNA disposed within the nanoporous silica core (preferably supercoiled in order to more efficiently package the DNA into protocells) which is optionally modified with a nuclear localization sequence to assist in localizing protocells within the nucleus of the cancer cell and the ability to express peptides involved in therapy (apoptosis / cell death) of the cancer cell or as a reporter, a targeting peptide which targets cancer cells in tissue to be treated such that binding of the protocell to the targeted cells is specific and enhanced and a fusogenic peptide that promotes endosomal escape of protocells and encapsulated DNA. Protocells according to the present invention may be used to treat cancer, especially including hepatocellular (liver) cancer using novel binding peptides (c-MET peptides) which selectively bind to hepatocellular tissue or to function in diagnosis of cancer, including cancer treatment and drug discovery.

Compositions and methods for improved delivery of macromolecules into eukaryotic cells are provided. Fusogenic peptides from fusion proteins of non-enveloped viruses enhance the efficiency of transfection of eukaryotic cells mediated by transfection agents such as cationic lipids, polycationic polymers such as PEI and dendrimers. These fusogenic peptides are used as part of a transfection complex that efficiently delivers a macromolecule, for example, a nucleic acid, into a eukaryotic cell. Novel cationic lipids and compositions of cationic lipids also are provided that may be used for the introduction of macromolecules such as nucleic acids, proteins and peptides into a variety of cells and tissues. The lipids can be used alone, in combination with other lipids and / or in combination with fusogenic peptides to prepare transfection complexes.

The invention discloses a tumor-targeted CD38-pH low insertion peptide (pHLIP) fusion peptide. The fusion peptide is formed by connecting a pHLIP and a functional structure domain of CD38. The tumor microenvironment is acidic, under the acidic environment, the pHLIP can be inserted into a tumor cell membrane, by utilizing the properties of the pHLIP, the CD38 connected with the pHLIP is positionedon the surface of the tumor cell membrane in a targeted mode, through the technology, original tumor cells with tumor cell surfaces not expressing the CD38 can also be marked by the CD38, and thus antibody drugs aiming at the CD38 can exert the effects on the original tumor cells not expressing the CD38 as well. Through the research results, the indications of a specific tumor antibody drug are expanded, and clinical application prospects are good.

A method is disclosed for encapsulating plasmids, oligonucleotides or negatively-charged drugs into liposomes having a different lipid composition between their inner and outer membrane bilayers and able to reach primary tumors and their metastases after intravenous injection to animals and humans. The formulation method includes complex formation between DNA with cationic lipid molecules and fusogenic / NLS peptide conjugates composed of a hydrophobic chain of about 10-20 amino acids and also containing four or more histidine residues or NLS at their one end. The encapsulated molecules display therapeutic efficacy in eradicating a variety of solid human tumors including but not limited to breast carcinoma and prostate carcinoma. Combination of the plasmids, oligonucleotides or negatively-charged drugs with other anti-neoplastic drugs (the positively-charged cis-platin, doxorubicin) encapsulated into liposomes are of therapeutic value. Also of therapeutic value in cancer eradication are combinations of encapsulated the plasmids, oligonucleotides or negatively-charged drugs with HSV-tk plus encapsulated ganciclovir.