University of Pennsylvania

The Wistar Institute

David Nathan Levy

David B Weiner

Yosef Refaeli

William Valentine Williams

Velpandi Ayyavoo

Pharmaceutical compositions comprising the HIV protein vpr or nucleic acid molecule encoding vpr are disclosed. Also disclosed are methods of treating patients suffering from diseases characterized by hyperproliferating undifferentiated cells such as cancer by administering such compositions. Methods of identifying compounds which have anti-HIV activity are disclosed, in particular, methods of identifying compounds which modulate the activity of vpr and of identifying compounds which inhibit vpr binding to the HIV protein gag.

VPR function and activity

Method of inhibiting proliferation of cells using vpr protein or nucleotide sequences that encode vpr are disclosed. Method of preventing lymphocyte activation using vpr protein or nucleotide sequences that encode vpr are disclosed. Methods of treating an individual diagnosed with or suspected of suffering from autoimmune disease, diseases characterized by proliferating cells and graft versus host disease by administering vpr protein or a functional fragment thereof, or a nucleic acid molecule that comprises a nucleotide sequence that encodes vpr protein or a functional fragment thereof are disclosed. Conjugated compositions for delivery of active agents to the nucleus of cells are disclosed.

Compositions and methods for the abrogation of cellular proliferation utilizing the human immunodeficiency virus VPR protein

The present invention is directed toward methods of identifying compounds which inhibit the human immunodeficiency virus (HIV) viral protein R (Vpr) from stimulating the differentiation of undifferentiated cells. This invention takes advantage of the observation that cell lines from rhabdomyosarcomas, which are tumors of muscle origin, have been used as models of CD4-independent HIV infection. These cell lines can be induced to differentiate in vitro. The vpr gene of HIV-1 is sufficient for the differentiation of the human rhabdomyosarcoma cell line TE671. Differentiated cells are characterized by great enlargement, altered morphology, lack of replication, and high level expression of the muscle-specific protein myosin. Morphological differentiation and inhibition of proliferation of other transformed cell lines following vpr expression was also observed. This invention also relates toward methods of identifying compounds which inhibit HIV Vpr binding to Gag. These screening methods should facilitate the identification and development of antiviral agents.

Identification of compounds that modulate HIV-1 vpr protein activity

A method for treating an individual exposed to or infected with HIV is disclosed which comprises administering to said individual a therapeutically effective amount of one or more compounds which inhibit or prevent replication of said HIV by interfering with the replicative or other essential functions of Vpr expressed by said HIV, by interactively blocking the Vpr target in human cells, and thereby preventing translocation of the Vpr/target complex from the cytosol of said human cells to the nuclei of said cells, where Vpr carries on activities essential to replication of HIV. In preferred embodiments, the compound or compounds which interactively block the target are steroid hormone receptor antagonists, glucocorticoid receptor antagonists, or glucocorticoid receptor Type II antagonists, especially mifepristone (RU-486). Pharmaceutical compositions comprising these compounds, as well as a method for identifying them and a kit for use therein, are also disclosed.

Methods and compositions for inhibiting HIV replication

VPR receptor protein

The present invention provides compositions and methods for targeting recombinant retroviral particles specifically to cells of interest for delivery of desired therapeutic or toxic agents. The invention provides chimeric nucleotide constructs, chimeric proteins formed of a selected viral envelope gene from which a selected sequence has been deleted and into which has been inserted all or an effective portion of a heterologous ligand, said ligand or portion thereof capable of binding to a selected receptor, recombinant viral particles formed of the chimeric proteins, a biological mediator for delivery to the target cell; and retroviral gag and pol proteins. The lack of retroviral nucleic acid renders the viral particle replication defective and non-pathogenic.

Chimeric envelope proteins for viral targeting

Human and simian immunodeficiency viruses (HIV/SIVs) contain, in addition to the canonical gag/pol/env genes, additional small open reading frames (ORFs) encoding gene products, including the 96-amino acid 15-kDa virion-associated HIV-1 Vpr gene product. Vpr functions as a regulator of cellular processes related to HIV replication. A biologically active recombinant HIV-1 Vpr protein was employed as a ligand to identify its cognate cellular target(s). A novel 41-kDa cytosolic viral protein R interacting protein, designated Rip-1, was identified using the recited assay. Rip-1 displays a wide-tissue distribution, including relevant targets of HIV infection. HIV-1 Vpr induced nuclear translocation of Rip-1. This invention provides novel biochemical reagents and methods that will facilitate the identification of antiviral agents.

Growing community of inventors

Philadelphia, PA, United States of America

David Nathan Levy