Abstract: The present invention relates to a method of inducing a CD8+ CTL response to a molecule in an individual deficient in CD4+ T cells comprising administering to the individual an hsp or a portion of an ATP binding domain of an hsp joined to the molecule. In one embodiment, the present invention relates to a method of treating HIV in an individual deficient in CD4+T cells comprising administering to the individual an hsp or a portion of an ATP binding domain of an hsp joined to the molecule. Also encompassed by the present invention is a method of inducing a CD4+ independent CTL response in an individual comprising administering to the individual a portion of an ATP binding domain of an hsp joined to the molecule. The present invention also relates to a method of inducing a CD8+ CTL response in an individual comprising administering to the individual a portion of an ATP binding domain of an hsp joined to the molecule.

Abstract: The present invention provides methods and compositions comprising a population of alphavirus replicon particles comprising two or more isolated nucleic acids selected from 1) an isolated nucleic acid encoding an env gene product or an immunogenic fragment thereof of a human immunodeficiency virus, 2) an isolated nucleic acid encoding a gag gene product or an immunogenic fragment thereof of a human immunodeficiency virus, wherein the gag gene product or immunogenic fragment thereof is modified to inhibit formation of virus-like particles containing the gag gene product or the immunogenic fragment thereof and their release from a cell, and 3) an isolated nucleic acid encoding a pol gene product or an immunogenic fragment thereof of a human immunodeficiency virus, wherein the pol gene product or immunogenic fragment thereof is modified to inhibit protease, integrase, RNase H and/or reverse transcriptase activity, and wherein the nucleic acids are each contained within a separate alphavirus replicon particle.

Abstract: A method of searching for and obtaining a vaccine against the pathogenic effects related to the infection of an animal or human host by a retrovirus that penetrates into a target cell of the host, and a vaccine obtained by the method are provided. The method includes preparing candidate vaccine agents based on a polypeptide comprising at least part of an envelope protein of a pathogenic strain of the retrovirus and selecting as the vaccine a modified polypeptide chosen from polypeptides that induces an immune response directed against an immunodominant region of an envelope protein of the retrovirus and not against a protein of the host.

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 in vivo administration including to humans and in diagnosis.

Abstract: Methods for immunizing, and immunogen pharmaceutical compositions for eliciting a heterologous immune response to HIV-1 in an animal, preferably a human, are provided, utilizing a modified HIV-1 envelope protein or fragment or DNA encoding a modified HIV-1 envelope protein or fragment, the modified protein having a HIV-1 envelope protein V2 region deletion. A humoral response against heterologous HIV-1 strains is achieved.

Abstract: The present invention provides for peptide conjugate compositions, methods of using the peptide conjugate compositions, and pharmaceutical compositions comprising the peptide conjugate compositions. The peptide conjugate compositions comprise peptides with amino acid sequences similar to the gp120 principal neutralizing domain (PND) of HIV, gp41, and Nef (p27) of HIV and carriers which enhance immunogenicity. The peptide conjugate compositions of the present invention may comprise a multivalent cocktail of several different peptide conjugates. Also provided by present invention is a method for reducing the level of HIV titers in a mammal by administering to the mammal a peptide composition of the present invention in an amount effective to reduce the level of HIV titers. The peptide conjugate compositions of the present invention induce prolonged antibody response in serum, a high level of antibody in the mucosa, and the production of cytotoxic lymphocytes.

Abstract: The subject invention pertains to novel methods and compositions for protecting cats from infection by a broad range of FIV strains using a multi-subtype FIV vaccine. Multi-subtype FIV vaccines comprising either cell free whole virus or cell lines infected with viruses are described. Methods for vaccinating cats with the subject vaccine compositions are also described. Cats vaccinated according to the methods and compositions of the subject invention exhibit protective humoral and cellular immune responses to FIV when challenged with homologous or heterologous strains of FIV. The subject invention also pertains to novel feline cell lines that are susceptible to infection by FIV and their methods of use.

Abstract: Immunologically active peptides which are derived from a novel immunodeficiency virus which has the designation MVP5180/91 are described. A diagnostic composition containing such a peptide and methods of detecting an antibody against a retrovirus that causes immune deficiency using such diagnostic composition are also described. A kit containing the immunologically active peptides is also described. An immunogen and method of immunizing a mammal against HIV infection using the immunologically active peptides is described. DNA encoding the peptides and methods of detecting nucleic acids encoding HIV viruses are also described.

Abstract: The molecular cloning and characterization of a novel human retrovirus, designated lymphadenopathy-associated virus, or LAV, is disclosed. LAV was originally isolated from a patient with acquired immune deficiency syndrome (AIDS). A cloned LAV complementary DNA (cDNA) was used to screen a library of recombinant phages constructed from the genomic DNA of LAV-infected T lymphocytes. The nucleotide sequence of an insert obtained from the recombinant phage clone &lgr;J19 was ascertained through M13 shotgun cloning and the dideoxy chain termination sequencing method. The env coding region was identified and various hydrophilic peptides obtained therefrom. These peptides correspond to amino acids 551-577, 594-603, 621-630, 657-679, and 719-758 of the LAV envelope glycoprotein. These peptides should provide suitable diagnostic reagents for the detection LAV-specific antibodies and for the generation of LAV-specific immunological reagents.

Abstract: The invention provides a method of generating a set of polypeptide antigens derived from a protein (or portion thereof) which is expressed with some degree of sequence heterogeneity among naturally or artificially induced variants of the protein. The purpose is to provide a mix of antigens which can be used to immunize against the variants and, preferably, possible unknown or new variants that may arise.

Abstract: The present invention is directed to genetically engineered, membrane-enveloped viruses with deletion mutations in the protein transmembrane domains. Also provided are viral vaccines based on the engineered viruses, methods of producing and using such vaccines.

Abstract: The invention describes the expression of a human immunodeficiency virus (HIV) type 1 provirus (F12-HIV) cloned from a nonproducer, chronically-infected CD4 down-regulated Hut-78 cell clone (F12) which does not lead to the formation of viral particles and, upon transfection in HeLa CD4+ cells, confers resistance to HIV superinfection without affecting CD4 receptor exposure. A Moloney murine leukemia virus-based retroviral vector containing an F12-HIV genome lacking the 3′ long terminal repeat (LTR) and part of the nef gene, expressed under the control of its 5′ LTR, was constructed to facilitate the transfer of the anti-HIV properties of F12-HIV into human cells. The F12-HIV genome was inserted in an orientation opposite to that of the murine leukemia virus transcriptional unit and was designated the N2/F12-HIV nef− antisense vector. Lymphoblastoid CEMss cells, as well as human peripheral blood lymphocytes, were successfully transduced by the recombinant retrovirus.

Abstract: The present invention provides, among other things, methods of removing virus from a sample, a composition comprising a solid support matrix to which is attached a cyanovirin, a conjugate comprising a cyanovirin coupled to at least one effector component, a composition comprising such a conjugate, methods of inhibiting prophylactically or therapeutically a viral infection of a host, and a matrix-anchored anti-cyanovirin antibody.

Abstract: Retroviruses associated with Acquired Immune Deficiency Syndrome (AIDS), including Lymphadenopathy Associated Virus (LAV), are isolated from the sera of patients afflicted with Lymphadenopathy Syndrome (LAS) or AIDS. LAV is a Human Immunodeficiency Virus (HIV). Viral extract, structural proteins and other fractions of the retrovirus immunologically recongize the sera of such patients. Immunological reaction is used to detect antibodies that specifically bind to antigenic sites of the retrovirus in samples of body fluids from patients with AIDS or risk of AIDS.

Abstract: A method is provided for enhancing the production of an infectious retrovirus comprising an envelope polypeptide in a producer cell which method comprises inhibiting the expression or activity in the producer cell of an endogenous receptor which is capable of binding to the envelope polypeptide of said retroviruses.

Abstract: The present invention relates to a novel human immunodeficiency virus (HIV) capable of inducing lymphadenopathies (LAS) and acquired immune deficiency syndromes (AIDS) in patients which has been designated the lymphadenopathy associated virus strain MAL (LAVMAL). Although the overall genomic organization of LAVMAL is similar to other known HIV-1 isolates such as LAVBRU and HTLV-III, nevertheless, this virus also displays considerable genotypic and phenotypic diversity as compared to these isolates. A proviral molecular clone of the virus was obtained and characterized. The complete nucleotide sequence of this clone was ascertained and putative regulatory regions (e.g., U3, R, U5,), regulatory elements (e.g., the TATA box, AATAAA polyadenylation signal, primer binding site), and open reading frames (e.g., Gag, Pol, Env, Vif, Vpr, Tat, Rev, Nef) identified. Of particular interest are unique polypeptides derived from the viral envelope.

Abstract: The development of general approaches for the isolation of efficient antivirals is becoming increasingly important. The genetic suppressor element (GSE) technology is an approach based on the functional expression and selection of efficient genetic inhibitors from random fragment libraries derived from a gene or genome of interest. We have applied this technology to isolate potent genetic inhibitors against the human immunodeficiency virus type 1 (HIV-1) The strategy employed involved the following steps: 1) fragmenting the HIV-1 genome into 100-700 base pair (bp) fragments; 2) inserting the fragments into expression vectors to form an expression library; 3) transferring the expression library into a population of cells (e.g., OM10.1) containing an inducible latent HIV-1 provirus; 4) selecting a subpopulation of cells which contain a subset of the expression library enriched for HIV-1 GSE by monitoring the expression of a cellular (e.g., CD4) or viral (e.g.

Abstract: A purified polypeptide having an epitope of an antigenic polypeptide of FIV.

Abstract: Methods and compositions for treatment, diagnosis, and prevention of a virus comprise administering to a patient antibodies which react with regions of viral proteins and result in neutralization of infectivity and inactivation of functionally essential events in the life cycle of the virus. The antibodies recognize viral epitopes which fail to elicit an immune response in man when encountered through infection or naturally through the environment. In a preferred embodiment, the invention provides compositions and methods useful in the treatment and diagnosis of human immunodeficiency virus (HIV) infections.

Abstract: The invention concerns epitopes of the HIV virus gp160 protein, that are immunologically homologous to epitopes of the protein family of the human major histocompatibility complex HLA, to be used for diagnosing and immunization.

Abstract: The invention provides methods and compositions for expanding cells that are not abundant or are difficult to obtain in pure form in culture, are in short supply (e.g., human cells), or have brief lifetimes in culture, using fusion polypeptide. The fusion polypeptide has a first region containing a translocation carrier moiety having the function of a transport polypeptide amino acid sequence from, e.g., herpesviral VP22, HIV TAT, Antp HD, Arg repeats, or a cationic polymer, or from homologues or fragments thereof, and a second region with a polypeptide having cell immortalization activity, a polypeptide having telomerase-specific activity, or a polypeptide having telomerase gene activation activity. The resulting cells of the invention are suitable for use in cell therapy.

Abstract: Activation of &agr;2-macroglobulin (&agr;2M) with a nucleophilic compound followed by incubation of the activated &agr;2M at elevated temperature with a biomolecule results in covalent incorporation of the intact biomolecule into the &agr;2M molecule, without the use of proteinases. The thus-formed structurally defined and stable complex may be used as an antigen for stimulating the immune response, for example, in the form of a vaccine. Enhanced antigen presentation of a particular biomolecule is provided, especially for those that are poorly immunogenic; reduction of the immunodominance of particular epitopes is also provided.

Abstract: A composition which elicits antibodies to multiple known variants of Tat protein of HIV-1 of both the B and non-B clades contains the peptide R1-Asp-Pro-Asn-Leu-Asp-Pro-Trp-Asn-R2 SEQ ID NO: 23, and preferably an additional at least two variants of a peptide or polypeptide of the formula: R1-Asp-Pro-Y7-Leu-Glu-Pro-Trp-Z12-R2 SEQ ID NO: 8. In this composition, at least one of the two variants contains Arg at Y7 and Lys at Z12, and in at least a second of the two variants Y7 is Asn and Z12 is Asn. Vaccinal and pharmaceutical compositions can contain one or more such peptides associated with carrier proteins, associated in multiple antigenic peptides, or as part of recombinant proteins. Diagnostic compositions and uses are described for assessing the immune status of vaccinated patients.

Abstract: An HIV-1 type (or subtype) O retrovirus protein, or a natural or synthetic polypeptide or peptide including at least a part of said protein, which is capable of being recognised by antibodies isolated from a serum resulting from infection by an HIV-1 type O VAU strain or an HIV-1 type (or subtype) O DUR strain.

Abstract: The present invention relates to therapeutic protocols and pharmaceutical compositions designed to target topo I for the treatment of HIV infection. The invention relates to therapeutic modalities and pharmaceutical compositions for the treatment of HIV-infection using human topo I and its interaction with HIV gag and RT as a target for intervention. The invention further relates to the use of human topo I to enhance the activity of RT. The present invention also relates to the expression of human topo I in transgenic animals, in particular mice, as a system to study the HIV life cycle and to screen agents for their ability to interfere with the HIV life cycle.

Abstract: An adenoviral vector is described which carries a codon-optimized gag gene, along with a heterologous promoter and transcription terminator. This viral vaccine can effectively prevent HIV infection when administered to humans either alone or as part of a prime and boost regime also with a vaccine plasmid.

Abstract: The invention is drawn is to peptides encoded by the feline immunodeficiency virus (FIV) env gene and their immunoprophylactic applications (prevention and treatment of feline immunodeficiency). Said peptides, capable of inducing a certain degree of protection against FIV infection are selected from the group consisting of: peptides containing 12 to 19 amino acids which correspond to the following: Lys-Lys-Gly-Leu-Gln-Gln-Leu-Gln-Glu-Trp-Glu-Asp-Trp-Val -Gly-Trp-Ile-Gly-Asn (SEQ ID NO:1); and peptides of not more than 50 amino acids comprising said sequence set forth by SEQ ID NO:1.

Abstract: Multiple branch peptide constructions formed from peptides derived from the envelope transmembrane glycoprotein gp41 of HIV, and including the consensus sequence RQGY preceded by 0 to 4 amino acid residues and succeeded by 2 to 4 amino acid residues, most preferably RQGYSPL, show increased receptor affinity and prevent cell-to-cell fusion. They have a direct virostatic effect. Because they present the same peptide sequence several times, these MBPCs are able to neutralize in vitro the different steps of virus envelope/cell membrane fusion, and infected cell membrane/uninfected cell membrane fusion of several strains of HIV-1 and HIV-2. These results open a potential use in treatment of HIV infection.

Abstract: A method for nucleic acid immunization which results in a cell-mediated immunological response to a selected antigen is disclosed. The method utilizes the T7 RNA infection/transfection system which provides for the controlled, transient cytoplasmic expression of a given antigen and which elicits the production of class I MHC restricted CTLs.

Abstract: The present invention is directed toward nucleic acids containing the full-length human immunodeficiency virus type 2 ROD (HIV-2ROD) pol gene. HIV-2, which was originally designated lymphadenopathy-associated virus type II (LAV-II), was isolated from AIDS patients in West Africa. The virus is genotypically and phenotypically distinct from HIV-1 and bears a closer genetic relationship to the simian immunodeficiency virus (SIV). The present invention describes the preparation of HIV-2ROD proviral molecular clones from a genomic lambda phage library of CD4+-infected cells. The complete nucleotide sequence of the full-length genome was determined and the putative gag, pol, env, vif (Q), vpr (R), vpx (X), nef (F), tat, and rev (art) genes identified. The claimed invention is directed toward nucleic acids containing the full-length HIV-2ROD pol gene (nt 1829-4936). These nucleic acids should prove useful as diagnostic reagents for the detection of HIV-2 and facilitate expression of the pol gene product.

Abstract: The present invention provides isolated and purified DNA encoding feline CD80 (B7-1) ligand, feline CD86 (B7-2) ligand, feline CD28 receptor, or feline CTLA-4 (CD152) receptor, as well as vectors comprising nucleic acid encoding feline CD80, feline CD86, feline CD28, or feline CTLA-4. The present invention provides a host cells transformed with CD80-encoding vectors, CD86-encoding vectors, CD28-encoding vectors, or CTLA-4-encoding vectors. The invention provides polypeptides encoded by the nucleic acid of feline CD80, feline CD86, feline CD28, or feline CTLA-4.

Abstract: An antigen/antibody specificity exchanger is disclosed. It comprises: A) an amino-acid sequence corresponding to an amino-acid sequence of an antibody which specifically binds to a certain antigen, including hapten, B) linked by a link to C) an amino-acid sequence to which a certain antibody binds. Also, a diagnostic reagent comprising an antigen/antibody specificity exchanger according to the invention is disclosed. Said reagent may be e.g. used instead of antisera or monoclonal antibodies in in vitro testing systems, such as immunological tests. Further, a method of treating a disease or disorder caused by a known antigen in an individual in need of an increased number of antigen-specific antibodies is disclosed. In the method a tailor-made antigen/antibody specificity exchanger of the invention is issued. Said method may be e.g. used to redirect a patient's antibodies against poliovirus to fight HIV infection in said patient.

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: The current invention relates to methods of generating immunogens that elicit broadly neutralizing antibodies which target regions of viral envelope proteins such as the gp 120/gp41 complex of HIV-1. More specifically, the current invention involves using stabilizing peptides modeling the &agr;-helical regions of the ectodomain of the HIV-1 transmembrane protein to stabilize fusion-active intermediate structures which can be used as vaccine immunogens.

Abstract: The present invention relates to stress proteins and methods of modulating an individual's immune response. In particular, it relates to the use of such stress proteins in immune therapy and prophylaxis, which results in an induction or enhancement of an individual's immune response and as an immunotherapeutic agent which results in a decrease of an individual's immune response to his or her own cells. The present invention also relates to compositions comprising a stress protein joined to another component, such as a fusion protein in which a stress protein is fused to an antigen. Further, the present invention relates to a method of generating antibodies to a substance using a conjugate comprised of a stress protein joined to the substance.

Abstract: Methods and kits for the in vitro detection of antibodies of an HIV variant are disclosed. In particular, the detection of HIV-1 variants, such as LAVBRU, LAVELI, LAVMAL, are taught by using an immunologically distinct antigen of these HIV variants to detect the antibodies of these variants. Moreover, the immunological characteristics of the HIV-1 variants of the invention are disclosed.

Abstract: The present invention is directed toward nucleic-acid based methodologies for the detection of human immunodeficiency virus (HIV) nucleic acids in a sample. A novel HIV-1 isolate, designated MVP5180/91, was isolated from a West African Cameroonian patient with immunodeficiency. Nucleic acid and amino acid sequence comparisons of this isolate, with other HIV-1 strains of subtypes A-E and HIV-2 isolates, demonstrated that this virus shares only limited homology with other known HIV-1 and -2 isolates. However, this virus does display some genetic relatedness to another Cameroonian isolate designated ANT-70. These viruses form the basis for a new HIV-1 group which has been designated subtype O. An immunologically important epitope, corresponding to amino acids 601-623 of the MVP5180/91 transmembrane envelope glycoprotein, was identified. Labeled nucleic acids can be prepared from the nucleotide sequence encoding this region and employed in standard hybridization assays to detect HIV-1 nucleic acids.

Abstract: Methods and compositions for treatment, diagnosis, and prevention of a virus comprise administering to a patient antibodies which react with regions of viral proteins and result in neutralization of infectivity and inactivation of functionally essential events in the life cycle of the virus. The antibodies recognize viral epitopes which fail to elicit an immune response in man when encountered through infection or naturally through the environment. In a preferred embodiment, the invention provides compositions and methods useful in the treatment and diagnosis of human immunodeficiency virus (HIV) infections.

Abstract: The present invention relates to stress proteins and methods of modulating an individual's immune response. In particular, it relates to the use of such stress proteins in immune therapy and prophylaxis, which results in an induction or enhancement of an individual's immune response and as an immunotherapeutic agent which results in a decrease of an individual's immune response to his or her own cells. The present invention also relates to compositions comprising a stress protein joined to another component, such as a fusion protein in which a stress protein is fused to an antigen. Further, the present invention relates to a method of generating antibodies to a substance using a conjugate comprised of a stress protein joined to the substance.

Abstract: A method for the rational design and preparation of vaccines based on HIV envelope polypeptides is described. In one embodiment, the method for making an HIV gp120 subunit vaccine for a geographic region comprises determining neutralizing epitopes in the V2 and/or C4 domains of gp120 of HIV isolates from the geographic region and selecting an HIV strain having gp120 a neutralizing epitope in the V2 or C4-domain which is common among isolates in the geographic region. In a preferred embodiment of the method, neutralizing epitopes for the V2, V3, and C4 domains of gp120 are determined. At least two HIV isolates having different neutralizing epitopes in the V2, V3, or C4 domain are selected and used to make the vaccine. The invention also provides a multivalent HIV gp120 subunit vaccine.

Abstract: A full-length feline immunodeficiency virus NCSU1 (FIV-NCSU1) genome (JSY3) was cloned directly from FIV-NCSU1-infected feline CD4+ lymphocyte (FCD4E) genomic DNA and identified by PCR amplification with 5′ long terminal repeat (LTR), gag, env, and 3′ LTR primer sets. Cell-free JSY3 virus was cytopathogenic for FCD4E lymphocytes but did not infect CrFK cells in vitro. To determine in vivo infectivity and pathogenesis, six young adult specific-pathogen-free cats were inoculated with cell-free JSY3 virus. Provirus was detected at 2 weeks postinfection (p.i.) and was still detectable at 25 weeks p.i. as determined by gag region PCR-Southern blot analysis of peripheral blood mononuclear cell lysates. Infectious virus was recovered from peripheral blood mononuclear cells at 6 and 25 weeks p.i., and an antibody response to FIV was detected by 4 weeks. In the acute phase of infection, JSY3 provirus was found only in the CD4+ lymphocyte subset; however, by 14 weeks p.i.

Abstract: Peptide sequences are disclosed which immunologically mimic proteins encoded by the env and gag regions of LAV-2, a retrovirus associated with AIDS. The peptide can be used in various specific binding assays to detect the presence of antibodies to LAV-2 in individuals previously exposed to the virus. The peptides enable one to distinguish the presence of antibodies to LAV-2 from antibodies to HIV-1.

Abstract: The present invention relates, in general, to human immunodeficiency virus (HIV) and, in particular, to an HLA-based HIV vaccine.

Abstract: Disclosed are methods for vaccine priming, using co-treatment, at a temporally similar or at a previous time, with a priming antibody capable of priming, or enhancing, or potentiating the effects of a vaccine, or vaccine composition. Also disclosed are methods of using this process to prevent or treat disease.

Abstract: Peptides immunologically related to proteins expressed by a viral agent, having a sequence of amino acids ordered by means of the protein informational analysis techniques using the Fourier transform method with reference to the amino acid sequence of a target antigen against which antibodies are desired to be formed, or lymphocytes desired to be directed. The sequence has in the Fourier spectrum, one or more frequencies of practically the same value as the frequency of frequencies characteristic of the target antigen.

Abstract: Peptide constructs comprised of multideterminant T helper peptides from the envelope glycoprotein of HIV previously identified to induce proliferative responses in four different haplotypes of mice and IL-2 responses in 52-73% of HIV positive, flu positive patients (cluster peptides), were co-linearly synthesized with the peptide 18 of the V3 loop of HIV-1 gp 160, corresponding to the principal neutralizing determinant of HIV-IIIB and also shown to contain a dominant CTL epitope. Cognate help for peptide 18 antibody was elicited following a single immunization in all strains of mice which had previously responded to a T cell epitope encompassed by the peptides. In two strains of mice, the level of neutralizing antibody achieved was comparable to levels adequate for protection from homologous viral challenge in chimpanzees. After a single boost, much higher antibody titers for 90% neutralization in the range of 1:1000 to 1:16,000 were achieved.

Abstract: Native and recombinant peptides which elicit anti-HIV immune response are provided.

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: A heteroconjugate is formed by linking a T cell binding ligand (TCBL) such as Peptide J of &bgr;-2 microglobulin to a modified HGP-30 antigentic peptide fragment of p17 gag peptide, such as, for example A T L  Y S V  H Q R  I D V  K D T (SEQ ID NO: 5) K E A  L E K  I E E  E Q N  K S The heteroconjugate is effective in eliciting a THI directed immune response and provides a vaccine composition for treating or preventing AIDS.

Abstract: This invention includes the conception of T-independent conjugate-vaccines and its application in the induction of antigen specific IgA response. We demonstrated that 1) &agr;(1,6)dextran can elicit a markedly enhanced IgA response in T-cell free mice (20-50 fold higher than in normal mice); 2)co-injection of the molecule with other antigens can enhance the IgA response to the co-antigen; and 3)a dextran-Gag conjugate can elicit the Gag-specific IgA. Thus, the invention identified &agr;(1,6)dextran as a carrier molecule for producing the T-independent conjugates and as an adjuvant for the enhancement of IgA production. The T-independent property of these conjugates makes it especially useful in vaccinations against HIV and other infectious and non-infectious diseases associated with T-cell deficiency.