The United States of America, As Represented by the Secretary, Department of Health and Human Services

The United States of America As Represented by the Department of Health

Mutsunori Shirai

Jay A Berzofsky

Peter L Nara

C David Pendleton

Jeffrey D Ahlers

Stephen M Feinstone

Toshiyuki Taskeshita

Steven Kozlowski

C David Pendelton

Toshitaka Akatsuka

David H Margulies

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. Spleen cells from mice of three distinct MHC haplotypes sharing the Dclass I MHC molecule but with different class II molecules, immunized with the compound peptides, exhibited enhanced gp160-specific CTL activity.

Peptides which elicit a high neutralizing antibody titer, cytotoxic T lymphocyte response and T helper cell response in a broad range of MHC type recipients

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. Spleen cells from mice of three distinct MHC haplotypes sharing the D,class I MHC molecule but with different class II molecules, immunized with the compound peptides, exhibited enhanced gp160-specific CTL activity.

Multideterminant peptides that elicit helper T-lymphocyte cytotoxic T-lymphocyte and neutralizing antibody responses against HIV-1

The invention is directed to peptides of the HIV-1 envelope protein presenting multiple immune determinants. The peptide elicits both humoral and cell-mediated immune responses in mice having a variety of MHC types. In other embodiments, the invention is directed to immunogens composed of the peptides and methods for immunization employing them.

Multideterminant peptides that elicit helper T-lymphocyte, cytotoxic T lymphocyte and neutralizing antibody responses against HIV-1

The cytotoxic T cell response to the protein encoded by the NS5 region of hepatitis C virus was determined using 28 peptides from NS5 which were selected by an amphipathicity algorithm as candidates for T cell epitopes. In BALB/c mice, a single relatively conserved epitope represented by a 16-residue synthetic peptide was presented by D.sup.d class I major histocompatibility complex (MHC) molecules to conventional CD4.sup.- CD8.sup.+ CTL. An exemplary peptide, which represents amino acid residues 2422-2437 of the polyprotein of the Chiron HCV1 isolate, had the amino acid sequence MSYSWTGALVTPCAAE [SEQ ID NO: 1]. A CTL line specific for this peptide recognized the two known natural variants of this NS5 sequence, each with conservative substitutions. Thus, CTL can recognize the product of the HCV NS5 gene, the probable RNA polymerase, in association with class I MHC molecules on model target cells and may recognize the same epitope on hepatocytes or any other cells infected with the virus.

Identification of peptides that stimulate hepatitis C virus specific

Peptides having high activity in the eliciting of a cytotoxic T lymphocyte response to the HIV-1 envelope glycoprotein gpl60 are described. The activation of 12-15 residue peptides by proteolytic degradation to shorter peptides is shown as are general techniques for characterizing such activation processes.

Potent peptide for stimulation of cytotoxic T lymphocytes specific for

This invention is directed toward a multideterminant human immunodeficiency virus type 1 (HIV-1) peptide which comprises a covalently linked T-helper (Th) lymphocyte epitope, cytotoxic T-lymphocyte (CTL) epitope, and an epitope capable of eliciting a neutralizing antibody response (AbN), wherein said peptide has the following amino acid sequence: KQIINMWQEVGKAMYAPPISGQIRRIHIGPGRAFYTTKN. This peptide has the further characteristic of evoking all three of these immune responses in hosts having a broad range of major histocompatibility complex (MHC) types. This peptide is useful as an immunogen to generate broad immune responses in a host, to assess immune responses in virally infected hosts, and as a diagnostic reagent to detect viral infection.

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Kagawa, Japan

Mutsunori Shirai