Anti-HIV peptides and proteins

Details Anti-HIV peptides and proteins Anti-HIV peptides and proteins

1999-08-24

2001-09-11

Nelson, Brett L. (Department: 1648)

Drug, bio-affecting and body treating compositions

Antigen, epitope, or other immunospecific immunoeffector

Virus or component thereof

C424S184100, C424S185100, C424S186100, C424S187100, C424S204100, C424S205100, C530S300000, C530S326000

Reexamination Certificate

active

06287572

ABSTRACT:

This invention relates to novel peptides and proteins useful against HIV infection, in particular, peptides and proteins which are derived from HIV p17 or p16 matrix proteins. The invention also relates to nucleic acids encoding the peptides and proteins and vectors containing the nucleic acids, in particular delivery vectors useful in gene therapy, such as retroviral vectors. The invention further relates to uses of the nucleic acids and vectors in gene therapy.
Despite intensive research efforts, there has been limited success in the development of low molecular weight compounds as treatments for HIV infection and AIDS. Similarly, it seems unlikely that a protective or therapeutic vaccine will be produced in the near future. This situation has led to recent proposals that greater emphasis should be given to biological therapeutics (Lehrman, 1994) and there is currently much interest in the prospect of gene therapy as a clinical approach to HIV-1 infection. Several molecules have been proposed as anti-HIV therapeutics, including ribozymes, trans-dominant proteins, scFv molecules, antisense constructs and TAR and RRE decoys (reviewed in Yu et al 1994). These molecules are envisaged to act both as therapy against already infected cells and as protective ‘intracellular immunisation’ (Baltimore, 1988) in uninfected cells. In addition, the use of toxins (suicide genes) or immunological markers has also been proposed as a means of killing infected cells so reducing the viral load in the patient.
Human immunodeficiency virus (HIV-1) has two genes that encode the structural proteins of the virus, these are the gag and env genes. The gag gene codes for a precursor protein call Gag or p55 which is proteolytically processed to produce the matrix protein (p17), the capsid protein (p24), the nucleocapsid protein (p7) and an additional protein, p6. Together these Gag derived proteins form the core of the virus particle. The correct functioning of these components is critical for viral particle production and infectivity.
The P17 protein forms the amino terminus of both the precursor Gag poly-protein p55
gag
, and p160
gag-pol
. Following proteolytic cleavage during particle maturation the p17 protein assembles into a shell referred to as the matrix (MA) directly underneath the lipid membrane. P17 pays a pivotal role at two stages in the life cycle of HIV-1. Late in infection it directs the precursor Gag polypeptide to the plasma membrane where assembly and budding occur (Gelderblom 1991) and early in a new infection it plays a role in penetration and uncoating (Yu et al 1992) and in mediating the nuclear transport of pre-integration complexes (Bukrinskaya et al 1996). The three dimensional structure of p17 has been determined and the protein is known to form a trimer which then assembles into the higher order structure of the viral core (Nermut et al 1994). The globular central core of the protein forms a compact fold consisting of four helices, with striking structural homology to IFN&ggr;. In addition, the protein contains a highly basic platform consisting of three &bgr;-strands.
A classical approach to inhibiting viral replication is to block the assembly of the viral components into virus particles by providing an excess of a mutant form of the normal viral proteins, the mutant protein is referred to as a trans-dominant inhibitor. It is generally thought that the mutant protein interferes with critical protein to protein interactions that are required to build up the structure of the viral particle. However other mechanisms can be envisaged such as the interference with cellular factors, such as the cyclophilins (Luban et al 1993) or protein kinases (Yu et al 1995) that might be required for proper virus particle formation. The approach was first proposed as a strategy for blocking HIV replication by Baltimore (1988) who subsequently demonstrated that the expression of a truncated form of one of the Gag proteins, p24, reduced viral replication (Trono et al 1989). This general approach has been developed by others (e.g. Lee and Linial 1995; Neidrig et al 1995; Lori et al 1994; Smythe et al 1994; Karacostas et al 1993) and is reviewed by Modrow et al 1994 & Meile and Lever (1996). The approach is however not always successful. For example Miele and Lever (1996) failed to protect cells against infection by using a modified p55. In addition the expression of full length proteins may be toxic as observed for p55 (Miele and Modrow op. cit.) or have other effects such as inhibition of lymphocyte proliferation as observed for wild type p17 (Hofman et al 1994). In addition in some cases the inhibition of viral replication by trans-dominant mutants of Gag was not dramatic. For example a truncated form of p24 was poorly effective in one study (Lori et al 1994). There is therefore a need for more effective inhibitors of viral assembly. There is also a need for inhibitors which are non-toxic or have acceptably low toxicity.
The present invention shows how to disrupt the function of the matrix protein p17, of HIV-1 and its counterpart p16 in HIV-2. We have identified novel molecules derived from the HIV-1 and HIV-2 Gag proteins, p17 and p
16
, that are potent inhibitors of viral replication. A first type of inhibitor comprises short peptides corresponding to part of the p17 or p16 protein and a second type of inhibitor comprises specific mutant forms of p17 or p16. The ability of these specific variants to inhibit HIV replication was not predicted.
The invention therefore provides in one aspect a peptide comprising an amino acid sequence of a part of the p17 protein of HIV-1 or of the p16 protein of HIV-2, from amino acid residues 31 to 45 or from amino acid residues 41 to 55 or a functional portion thereof, of which one or more residues may be conservatively substituted, said peptide capable of interfering with HIV replication.
In another aspect the invention provides a nucleic acid comprising at least one sequence encoding a peptide capable of interfering with HIV replication, which peptide comprises an amino acid sequence of a part of the p17 protein of HIV-1 or of the p16 protein of HIV-2, from amino acid residues :31 to 45 or a functional portion thereof, of which one or more residues may be conservatively substituted.
In another aspect the invention provides a nucleic acid comprising at least one sequence encoding a peptide capable of interfering with HIV replication, which peptide comprises an amino acid sequence of a part of the p17 protein of HIV-1 or of the p16 protein of HIV-2, from amino acid residues 41 to 55 or a functional portion thereof, of which one or more residues may be conservatively substituted.
Preferred peptides according to the invention are peptide 1 and peptide 2 designated by amino acid residues 31 to 45 and 41 to 55, respectively; and which may have conservative variations, in particular amino acid substitutions which do not significantly alter the characteristics of the peptide. Peptides 1 and 2 corresponding to the p17 amino acid sequence of the HXB2 HIV-2 isolate shown in
FIG. 2
are:
Peptide 1: LKHIVWASRELERFA [SEQ ID NO: 1]
Peptide 2: LERFAVNPGLLETSE [SEQ ID NO: 2].
FIGS. 6 and
7 show p17 and p16 from a range of isolates of HIV-1 and HIV-:2, indicating the locations of peptides 1 and 2 according to the invention, within those isolates.
However, it will be evident that functional peptides may still be obtained by reducing the length of the two regions defined herein as p17 and p16 residues 31 to 45 and 41 to 55. Also, it may be possible to retain the functions of peptides 1 and 2 using longer amino acid sequences containing one or more residues extending at either or both ends of the peptides. Such shorter or longer amino acid sequences can easily be defined by known methods and are included within the scope of the invention.
Peptides according to the invention can range in length e.g. from 5 to 30 amino acids or longer, or preferably 6 to 20 amino acids. 6 amino acid residues is generally the shortest length for an epitope of reasonable spec

Affiliated with

Also associated with

Rating

Anti-HIV peptides and proteins does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Anti-HIV peptides and proteins, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Anti-HIV peptides and proteins will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2515520