title: Induction of an antigen-specific CTL response by a conformationally biased agonist of human C5a anaphylatoxin as a molecular adjuvant.
abstract: A conformationally biased decapeptide agonist of human C5a anaphylatoxin (YSFKPMPLaR) was used as a molecular adjuvant in stimulating an Ag-specific CTL response against murine P815S target cells expressing an Ld-restricted CTL epitope of the hepatitis B surface Ag (HBsAg). Groups of BALB/c mice (H-2d) were immunized with aqueous solutions of the HBsAg CTL epitopes (IPQSLDSWWTSL and IPQSLDSWWTSLRR); the C5a agonist (YSFKPMPLaR); the C5a agonist and HBsAg CTL epitopes admixed (IPQSLDSWWTSL and IPQSLDSWWTSLRR + YSFKPMPLaR); the C5a-active, HBsAg CTL epitope-C5a agonist constructs (IPQSLDSWWTSLYSFKPMPLaR, IPQSLDSWWTSLRRYSFKPMPLaR, and IPQSLDSWWTSLRVRRYSFPMPLaR); a C5a-inactive, reverse-moiety construct (YSFKPMPLaRRRIPQSLDSWWTSL); and a C5a-attenuated, carboxyl-terminal-blocked construct (IPQSLDSWWTSLRRYSFKPMPLaRG). Ag-specific CD8+ CTL responses were observed after the secondary boost in the absence of any added adjuvant only in mice that were immunized with C5a-active contructs, IPQSLDSWWTSLRRYSFKPMPLaR and IPQSLDSWWTSLRVRRYSFKPMPLaR. These two C5a-active immunogens contained potential subtilisin-sensitive linker sequences between the HBsAg CTL epitope and the C5a agonist; i.e., a double-Arg (RR) and a furin protease sensitive sequence (RVRR). The introduction of these potentially cleavable sequences may be a method of increasing the likelihood of liberating the CTL epitope from the C5a agonist by intracellular proteases, thereby facilitating entry of the epitope into Ag-processing pathways via an exogenous route.
authors.affiliation: Corixa, Hamilton, MT 59840, USA.
authors.forename: J T
authors.initials: JT
authors.lastname: Ulrich
authors.forename: W
authors.initials: W
authors.lastname: Cieplak
authors.forename: N J
authors.initials: NJ
authors.lastname: Paczkowski
authors.forename: S M
authors.initials: SM
authors.lastname: Taylor
authors.forename: S D
authors.initials: SD
authors.lastname: Sanderson
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage / Q000819:agonists* / Q000737:chemistry* / Q000494:pharmacology; D000595:Amino Acid Sequence; D000818:Animals; D001120:Arginine / Q000008:administration & dosage / Q000737:chemistry / Q000276:immunology; D002478:Cells, Cultured; D015936:Complement C5a / Q000008:administration & dosage / Q000819:agonists* / Q000737:chemistry* / Q000276:immunology; D003602:Cytotoxicity, Immunologic; D010450:Endopeptidases / Q000737:chemistry / Q000276:immunology; D018984:Epitopes, T-Lymphocyte / Q000008:administration & dosage / Q000737:chemistry / Q000276:immunology*; D005260:Female; D006183:H-2 Antigens / Q000008:administration & dosage / Q000737:chemistry / Q000276:immunology; D006510:Hepatitis B Antibodies / Q000096:biosynthesis; D006514:Hepatitis B Surface Antigens / Q000008:administration & dosage / Q000276:immunology; D064532:Histocompatibility Antigen H-2D; D006801:Humans; D007279:Injections, Subcutaneous; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000008:administration & dosage / Q000138:chemical synthesis / Q000276:immunology / Q000494:pharmacology; D011487:Protein Conformation; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*
chemical_list: D000276:Adjuvants, Immunologic; D018984:Epitopes, T-Lymphocyte; D006183:H-2 Antigens; D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D064532:Histocompatibility Antigen H-2D; D010446:Peptide Fragments; D015936:Complement C5a; D001120:Arginine; D010450:Endopeptidases