593 results about "Retrovirus" patented technology

The present invention relates to a retroviral vector system comprising a packaging cell line that synthesize the core and enzymatic proteins of MLV virus from one or more gag and pol containing constructs and the envelope of MMTV virus from the same or an independent env containing construct, and to pseudotyped retroviral particles produced by culturing said retroviral vector system transfected with a MLV based retroviral vector, and isolation of said pseudotyped retroviral particles.

Non-infectious, retrovirus-like particles contain mutations to reduce gag-dependent RNA-packaging of the gag gene product, eliminate reverse transcriptase activity of the pol gene product, eliminate integrase activity of the pol gene product and eliminate RNase H activity of the pol gene product through genetic manipulation of the gag and pol genes. The corresponding nucleic acid molecules are described. The non-infectious, retrovirus-like particles have utility in diagnosis.

The present invention describes a comprehensive system for gene discovery using retrovirus that have been engineered to exhibit increased accessibility to genomic DNA, or to mutate and identify the chromosomal target sequences of DNA binding proteins. The strategy employs the combination of retroviral integrase/DNA binding protein fusion constructs and gene-trapping methodologies. This novel technology provides the ability to establish proviral integration at any location within the genome. In addition, it allows for the generation of a collection of eukaryotic cells in which each cell contains a mutation in a target gene or sequence for a known DNA binding protein which also allow for rapid in vivo functional analysis. Sequence information obtained for genes identified using the described methods identify a collection of eukaryotic genes related by, or directly or indirectly regulated by, a given DNA binding protein.

A method of inactivating a proviral DNA integrated into the genome of a host cell latently infected with a retrovirus by treating the host cell with a composition comprising a Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR)-associated endonuclease, and two or more different guide RNAs (gRNAs), wherein each of the at least two gRNAs is complementary to a different target nucleic acid sequence in a long terminal repeat (LTR) in the proviral DNA, and inactivating the proviral DNA. A composition for use in inactivating a proviral DNA integrated into the genome of a host cell latently infected with a retrovirus including isolated nucleic acid sequences comprising a CRISPR-associated endonuclease and a guide RNA, wherein the guide RNA is complementary to a target sequence in a human immunodeficiency virus.

We have made retrovirus particles displaying a functional antibody fragment. We fused the gene encoding an antibody fragment directed against a hapten with that encoding the viral envelope protein (Pr80env) of the ecotropic Moloney murine leukemia virus. The fusion gene was co-expressed in ecotropic retroviral packaging cells with a retroviral plasmid carrying the neomycin phosphotransferase gene (neo), and retroviral particles with specific hapten biding activities were recovered. Furthermore the hapten-binding particles were able to transfer the neo gene and the antibody-envelope fusion gene to mouse fibroblasts. In principle, the display of antibody fragments on the surface of recombinant retroviral particles could be used to target virus to cells for gene delivery, or to retain the virus in target tissues, or for the construction of libraries of viral display packages.

The present invention relates to retroviral vectors, particularly lentiviral vectors, pseudotyped with Sindbis envelope and targeted to specific cell types via a targeting moiety linked to the envelope.

Non-infectious, retrovirus-like particles comprise an assembly of an env gene product, a pol gene product and a gag gene product contain an antigenic marker which is non-retroviral or non-HIV retroviral. In one embodiment, the marker comprises an amino acid sequence containing an epitope inserted into the gag gene product at an antigenically-active insertion site. In another embodiment, the marker comprises an antigenic anchor sequence operatively connected to the env gene product replacing endogenous anchoring function. The corresponding nucleic acid molecules are described. The non-infectious, retrovirus-like particles have utility in in vivo administration including to humans and in diagnosis. The presence of the antigenic marker enables recognition that antiserum containing anti-retroviral antibodies has been generated by exposure to the non-infectious retrovirus-like particles by testing for antibodies specific to the antigenic marker.

Retroviral vectors are disclosed which include an insertion site for genes of interest and are capable of expressing high levels of the protein derived from the genes of interest in a wide variety of transfected cell types. Also disclosed are retroviral vectors lacking a selectable marker, thus rendering them suitable for human gene therapy in the treatment of a variety of disease states without the co-expression of a marker product, such as an antibiotic. These retroviral vectors are especially suited for use in certain packaging cell lines.

In one aspect, the invention provides methods and compositions for the expression of small RNA molecules within a cell using a retroviral vector (FIG. 1A). Small interfering RNA (siRNA) can be expressed using the methods of the invention within a cell. In a further aspect, the invention provides methods for producing siRNA encoding lentivirus where the siRNA activity may interfere with the lentiviral life cycle. In yet a further aspect, the invention provides methods for expression of a small RNA molecule within a cell, such as an siRNA capable of downregulating CCR5, wherein expression of the small RNA molecule is relatively non-cytotoxic to the cell. The invention also includes small RNA molecules, such as an siRNA capable of downregulating CCR5, that are relatively non-cytotoxic to cells.

Provided are compounds and pharmaceutically acceptable salts thereof, their pharmaceutical compositions, their methods of preparation, and their use for treating viral infections mediated by a member of the retrovirus family of viruses such as the Human Immunodeficiency Virus (HIV).

Chemical compounds that disrupt retroviral assembly and maturation are presented herein. More particularly, this disclosure provides small molecule compounds that disrupt the formation and maturation of virus particles and methods of using such small molecules to treat HIV-1 infection.

The present invention demonstrates that VSV-G-pseudotyped lentivirus vectors efficiently transduce AEC in primary culture and in vivo with transduction favored by virus application from the apical side. Transduction efficiency in AEC increased with increasing MOI and greatly exceeded that achieved with a similarly pseudotyped MLV retrovirus vector. The present invention also demonstrates the successful in vivo transfer of genes through lentivirus vector transduction. Mammals injected with lentivirus vector via the trachea expressed the reporter protein in alveolar epithelial cells within 48 to 72 hours after infection.

The present invention involves methods and compositions for increasing the susceptibility of target cells to transduction by gene transfer vectors. Specifically, it is proposed that increasing intracellular permeability in epithelial tissue increases the percentage of input vector that will transduce that target tissue. Specific examples show that receptors for retrovirus are preferentially accessible on the basolateral surface of airway epithelia, and permeabilizing such tissues results in greater infection with retrovirus. This has important implications in gene therapy, for example, to treat cystic fibrosis with the CFTR gene.

The present invention relates to a method of preventing or inhibiting viral infection of a cell and/or fusion between the envelope of a virus and the membranes of a cell targeted by the virus (thereby preventing delivery of the viral genome into the cell cytoplasm, a step required for. viral infection). The present invention particularly relates to the families of RNA viruses, including the arenaviruses, coronaviruses, filoviruses, orthomyxoviruses, paramyxoviruses, and retroviruses, having Class I membrane fusion proteins as the fusion proteins that mediate this fusion process. The present invention provides for a method of identifying a conserved motif or domain called the fusion initiation region (FIR) in these viruses. The present invention further provides for methods of preventing infection by such viruses, by interfering with their FIR. The present invention further provides for methods of treatment and prophylaxis of diseases induced by such viruses.

A method for removing retroviruses from liquid samples and a nanofiber containing liquid filtration medium that simultaneously exhibits high liquid permeability and high microorganism retention is disclosed. Retroviruses are removed from a liquid by passing the liquid through a porous nanofiber containing filtration medium having a retrovirus LRV greater than about 6, and the nanofiber(s) has a diameter from about 10 nm to about 100 nm. The filtration medium can be in the form of a fibrous electrospun polymeric nanofiber liquid filtration medium mat.