Abstract: 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.

Abstract: 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.

Abstract: An immunogenic retrovirus-like particle which is non-infectious and non-replicating and which is useful as a candidate vaccine component against retroviral infections, including AIDS and ATLL, is produced by genetic engineering. A DNA molecule comprising a retroviral genome devoid of long terminal repeats is incorporated into an expression vector, which is introduced into mammalian cells for expression of the retrovirus-like particle.

Abstract: Vectors for DNA immunization against cervical cancer comprise a nucleic acid molecule encoding at least one non-toxic T-cell epitope of the E6 and/or E7 antigens of a strain of human papilloma virus (HPV) associated with cervical cancer, such as HPV-16, and a promoter operatively coupled to the nucleic acid molecule for expression of the nucleic acid molecule in a host to which the vector is administered.

Abstract: Non-infectious, non-replicating immunogenic HIV-like particles are produced by stable longn-term constitutive expression in mammalian cells by eliminating elements toxic to the mammalian cells. An expression vector contains a nucleic acid molecule comprising a modified HIV genome devoid of long terminal repeats and wherein Tat and vpr sequences are functionally disabled and a constitutive promoter operatively connected to the modified HIV genome for constitutive expression of the modified genome to produce the HIV-like particles.

Abstract: 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.

Abstract: The present invention is concerned with the ability to differentiate between infection by HIV and immunization with an immunogenic preparation. Accordingly, the present invention provides a non-infectious, non-replicating, HIV retrovirus-like particle containing a heterologous antigenic marker, comprising an assembly of (a) an env gene product; (b) a pol gene product; (c) a gag gene product; and, (d) at least one non-retroviral, non-mammalian antigenic marker. The antigenic marker may have between 10 and 75 amino acid residues. In one embodiment, the amino acid sequence contains a tobacco mosaic virus (TMV) epitope obtained from the coat protein. In another embodiment, the marker is inserted into the gag gene product at an antigenically-active insertion site.

Abstract: An immunogenic retrovirus-like particle which is non-infectious and non-replicating and which is useful as a candidate vaccine component against retroviral infections, including AIDS and ATLL, is produced by genetic engineering. A DNA molecule comprising a retroviral genome devoid of long terminal repeats is incorporated into an expression vector, which is introduced into mammalian cells for expression of the retrovirus-like particle.

Abstract: The present invention is concerned with the ability to differentiate between infection by HIV and immunization with an immunogenic preparation. Accordingly, the present invention provides a non-infectious, non-replicating, HIV retrovirus-like particle containing a heterologous antigenic marker, comprising an assembly of (a) an env gene product; (b) a pol gene product; (c) a gag gene product; and, (d) at least one non-retroviral, non-mammalian antigenic marker. The antigenic marker may have between 5 and 100 amino acid residues. In one embodiment, the amino acid sequence contains a tobacco mosaic virus (TMV) epitope obtained from the coat protein. In another embodiment, the marker is inserted into the gag gene product at an antigenically-active insertion site.

Abstract: This invention is directed toward nucleic acids encoding self-assembled, non-infectious, non-replicating, immunogenic retrovirus-like particles comprising modified HIV-1 genomes devoid of long terminal repeats and containing nucleotide sequences encoding chimeric envelope glycoproteins. Retrovirus-like particles containing chimeric envelope glycoproteins were expressed in mammalian cells by using inducible promoters. One preferred embodiment discloses the engineering of a series of expression vectors in which a synthetic oligomer encoding gp120 residues 306 to 328 (amino acids YNKRKRIHIGP GRAFYTTKNIIG) from the V3 loop of the MN viral isolate was inserted at various positions within the endogenous HIV-1.sub.LAI env gene. Expression studies revealed that insertion of the heterologous V3(MN) loop segment resulted in the secretion of fully assembled HIV-like particles containing chimeric LAI/MN envelope glycoproteins. Both V3 loop epitopes were recognized by loop-specific neutralizing antibodies.

Abstract: 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.

Abstract: 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.

Abstract: This invention is directed toward self-assembled, non-infectious, non-replicating, immunogenic retrovirus-like particles comprising modified HIV-1 genomes devoid of long terminal repeats and containing nucleotide sequences encoding chimeric envelope glycoproteins. Retrovirus-like particles containing chimeric envelope glycoproteins were expressed in mammalian cells by using inducible promoters. One preferred embodiment discloses the engineering of a series of expression vectors in which a synthetic oligomer encoding gp120 residues 306 to 328 (amino acids YNKRKRIHIGP GRAFYTTKNIIG) from the V3 loop of the MN viral isolate was inserted at various positions within the endogenous HIV-1.sub.LAI env gene. Expression studies revealed that insertion of the heterologous V3(MN) loop segment resulted in the secretion of fully assembled HIV-like particles containing chimeric LAI/MN envelope glycoproteins. Both V3 loop epitopes were recognized by loop-specific neutralizing antibodies.

Abstract: 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.

Abstract: This invention is directed toward diagnostic kits and antigens useful for the detection of viral antigens in a test sample. The kit contains antigens obtained from self-assembled, non-infectious, non-replicating, immunogenic retrovirus-like particles comprising modified HIV-1 genomes devoid of long terminal repeats and containing nucleotide sequences encoding chimeric envelope glycoproteins. One preferred embodiment discloses the engineering of a series of expression vectors in which a synthetic oligomer encoding gp120 residues 306 to 328 (amino acids YNKRKRIHIGP GRAFYTTKNIIG) from the V3 loop of the MN viral isolate was inserted at various positions within the endogenous HIV-1.sub.LAI env gene. Expression studies revealed that insertion of the heterologous V3(MN) loop segment resulted in the secretion of fully assembled HIV-like particles containing chimeric LAI/MN envelope glycoproteins. Both V3 loop epitopes were recognized by loop-specific neutralizing antibodies.