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Abstract
Abstract
The study of proteins and peptides by mass spectrometry has been advanced by the development of matrix-assisted laser desorption/ionization and electrospray ionization. Proteins with masses > 100 kDa may be measured accurately at picomole sensitivities. Sequence analysis of peptides in mixtures at subpicomole quantities is possible by tandem mass spectrometry. Practical applications of the new technology to biological research are illustrated.
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Affiliation(s)
- D Arnott
- Department of Chemistry, University of Virginia, Charlottesville 22903
| | - J Shabanowitz
- Department of Chemistry, University of Virginia, Charlottesville 22903
| | - D F Hunt
- Department of Chemistry, University of Virginia, Charlottesville 22903
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2
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Penny S, Abelin J, Saeed A, Malaker S, Trantham P, Shabanowitz J, Ward S, Hunt D, Cobbold M. Phosphopeptides as novel tumour antigens in colorectal cancer. Eur J Cancer 2016. [DOI: 10.1016/s0959-8049(16)61751-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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3
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Recht J, Tsubota T, Tanny JC, Diaz RL, Berger JM, Zhang X, Garcia BA, Shabanowitz J, Burlingame AL, Hunt DF, Kaufman PD, Allis CD. Histone chaperone Asf1 is required for histone H3 lysine 56 acetylation, a modification associated with S phase in mitosis and meiosis. Proc Natl Acad Sci U S A 2006; 103:6988-93. [PMID: 16627621 PMCID: PMC1459006 DOI: 10.1073/pnas.0601676103] [Citation(s) in RCA: 198] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Histone acetylation affects many nuclear processes including transcription, chromatin assembly, and DNA damage repair. Acetylation of histone H3 lysine 56 (H3 K56ac) in budding yeast occurs during mitotic S phase and persists during DNA damage repair. Here, we show that H3 K56ac is also present during premeiotic S phase and is conserved in fission yeast. Furthermore, the H3 K56ac modification is not observed in the absence of the histone chaperone Asf1. asf1delta and H3 K56R mutants exhibit similar sensitivity to DNA damaging agents. Mutational analysis of Asf1 demonstrates that DNA damage sensitivity correlates with (i) decreased levels of H3 K56ac and (ii) a region implicated in histone binding. In contrast, multiple asf1 mutants that are resistant to DNA damage display WT levels of K56ac. These data suggest that maintenance of H3 K56 acetylation is a primary contribution of Asf1 to genome stability in yeast.
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Affiliation(s)
- J. Recht
- *Laboratory of Chromatin Biology, The Rockefeller University, New York, NY 10021
| | - T. Tsubota
- Program in Gene Function and Expression, University of Massachusetts Medical School, Worcester, MA 01605
| | - J. C. Tanny
- *Laboratory of Chromatin Biology, The Rockefeller University, New York, NY 10021
| | - R. L. Diaz
- *Laboratory of Chromatin Biology, The Rockefeller University, New York, NY 10021
| | - J. M. Berger
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720
| | - X. Zhang
- Department of Pharmaceutical Chemistry and Mass Spectrometry Facility, University of California, San Francisco, CA 94143; and
| | - B. A. Garcia
- Department of Chemistry, University of Virginia, Charlottesville, VA 22901
| | - J. Shabanowitz
- Department of Chemistry, University of Virginia, Charlottesville, VA 22901
| | - A. L. Burlingame
- Department of Pharmaceutical Chemistry and Mass Spectrometry Facility, University of California, San Francisco, CA 94143; and
| | - D. F. Hunt
- Department of Chemistry, University of Virginia, Charlottesville, VA 22901
| | - P. D. Kaufman
- Program in Gene Function and Expression, University of Massachusetts Medical School, Worcester, MA 01605
| | - C. D. Allis
- *Laboratory of Chromatin Biology, The Rockefeller University, New York, NY 10021
- To whom correspondence should be addressed at:
Laboratory of Chromatin Biology, The Rockefeller University, 1230 York Avenue, New York, NY 10021. E-mail:
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4
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Hopkins L, Polefrone J, Zarling A, Evans A, Shabanowitz J, Hunt D, Engelhard V. Differential expression of HLA-A2 and HLA-B7 phosphorylated peptides on cancer and non-cancer cells: New candidates for immunotherapy. Hum Immunol 2005. [DOI: 10.1016/j.humimm.2005.08.224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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5
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Bandholtz L, Guo Y, Palmberg C, Mattsson K, Ohlsson B, High A, Shabanowitz J, Hunt DF, Jörnvall H, Wigzell H, Agerberth B, Gudmundsson GH. Hsp90 binds CpG oligonucleotides directly: implications for hsp90 as a missing link in CpG signaling and recognition. Cell Mol Life Sci 2003; 60:422-9. [PMID: 12678505 DOI: 10.1007/s000180300035] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
CpG motifs originating from bacterial DNA (CpG DNA) can act as danger signals for the mammalian immune system. These CpG DNA motifs like many other pathogen-associated molecular patterns are believed to be recognized by a member of the toll-like receptor family, TLR-9. Here we show results suggesting that heat shock protein 90 (hsp90) is also implicated in the recognition of CpG DNA. Hsp90 was characterized as a binder to oligodeoxynucleotides (ODNs) containing CpG motifs (CpG ODNs) after several purification steps from crude protein extracts of peripheral blood mononuclear cells. This finding was further supported by direct binding of CpG ODNs to commercially available human hsp90. Additionally, immunohistochemistry studies showed redistribution of hsp90 upon CpG ODN uptake. Thus, we propose that hsp90 can act as a ligand transfer molecule and/or play a central role in the signaling cascade induced by CpG DNA.
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Affiliation(s)
- L Bandholtz
- Microbiology and Tumor Biology Center (MTC), Karolinska Institutet, 17177, Stockholm, Sweden
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6
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Hunt DF, Bone WM, Shabanowitz J, Rhodes J, Ballard JM. Sequence analysis of oligopeptides by secondary ion/collision activated dissociation mass spectrometry. Anal Chem 2002. [DOI: 10.1021/ac00234a035] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Kao H, Marto JA, Hoffmann TK, Shabanowitz J, Finkelstein SD, Whiteside TL, Hunt DF, Finn OJ. Identification of cyclin B1 as a shared human epithelial tumor-associated antigen recognized by T cells. J Exp Med 2001; 194:1313-23. [PMID: 11696596 PMCID: PMC2195974 DOI: 10.1084/jem.194.9.1313] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
We eluted peptides from class I molecules of HLA-A2.1(+) breast adenocarcinoma and loaded reverse phase high-performance liquid chromatography (HPLC) fractions onto dendritic cells to prime naive CD8(+) T cells. Fractions that supported growth of tumor-specific cytotoxic T lymphocytes were analyzed by nano-HPLC micro-ESI tandem mass spectrometry. Six HLA-A2.1-binding peptides, four 9-mers (P1-P4) differing in the COOH-terminal residue, and two 10-mers (P5 and P6) with an additional COOH-terminal alanine, were identified in one fraction. Peptide sequences were homologous to cyclin B1. We primed CD8(+) T cells from another HLA-A2.1(+) healthy donor with synthetic peptides and generated P4-specific responses. We also detected memory T cells specific for one or more of these peptides in patients with breast cancer and squamous cell carcinomas of the head and neck (SCCHN). T cells from one patient, restimulated once in vitro, could kill the tumor cell line from which the peptides were derived. Immunohistochemical analysis of tumor lines and tissue sections showed cyclin B1 overexpression and aberrant localization in the cytoplasm instead of the nucleus. Sequencing genomic DNA and cDNA corresponding to P1-P6 region showed that differences in COOH-terminal residues were not due to either DNA mutations or errors in transcription, suggesting a high error rate in translation of cyclin B1 protein in tumors.
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Affiliation(s)
- H Kao
- Department of Molecular Genetics and Biochemistry, University of Pittsburgh, Pittsburgh, PA 15261, USA
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8
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Fitton JE, Hunt D, Marasco J, Shabanowitz J, Winston S, Dell A. The amino acid sequence of delta haemolysin purified from a canine isolate ofS. aureus. FEBS Lett 2001. [DOI: 10.1016/0014-5793(84)80282-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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9
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Baginsky S, Shteiman-Kotler A, Liveanu V, Yehudai-Resheff S, Bellaoui M, Settlage RE, Shabanowitz J, Hunt DF, Schuster G, Gruissem W. Chloroplast PNPase exists as a homo-multimer enzyme complex that is distinct from the Escherichia coli degradosome. RNA 2001; 7:1464-1475. [PMID: 11680851 PMCID: PMC1370190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In Escherichia coli, the exoribonuclease polynucleotide phosphorylase (PNPase), the endoribonuclease RNase E, a DEAD-RNA helicase and the glycolytic enzyme enolase are associated with a high molecular weight complex, the degradosome. This complex has an important role in processing and degradation of RNA. Chloroplasts contain an exoribonuclease homologous to E. coli PNPase. Size exclusion chromatography revealed that chloroplast PNPase elutes as a 580-600 kDa complex, suggesting that it can form an enzyme complex similar to the E. coli degradosome. Biochemical and mass-spectrometric analysis showed, however, that PNPase is the only protein associated with the 580-600 kDa complex. Similarly, a purified recombinant chloroplast PNPase also eluted as a 580-600 kDa complex after gel filtration chromatography. These results suggest that chloroplast PNPase exists as a homo-multimer complex. No other chloroplast proteins were found to associate with chloroplast PNPase during affinity chromatography. Database analysis of proteins homologous to E. coli RNase E revealed that chloroplast and cyanobacterial proteins lack the C-terminal domain of the E. coli protein that is involved in assembly of the degradosome. Together, our results suggest that PNPase does not form a degradosome-like complex in the chloroplast. Thus, RNA processing and degradation in this organelle differ in several respects from those in E. coli.
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Affiliation(s)
- S Baginsky
- Institute of Plant Sciences, Swiss Federal Institute of Technology, ETH-Zentrum, Zürich
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10
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Pierce RA, Field ED, Mutis T, Golovina TN, Von Kap-Herr C, Wilke M, Pool J, Shabanowitz J, Pettenati MJ, Eisenlohr LC, Hunt DF, Goulmy E, Engelhard VH. The HA-2 minor histocompatibility antigen is derived from a diallelic gene encoding a novel human class I myosin protein. J Immunol 2001; 167:3223-30. [PMID: 11544309 DOI: 10.4049/jimmunol.167.6.3223] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Human minor histocompatibility Ags (mHag) present significant barriers to successful bone marrow transplantation. However, the structure of human mHag and the basis for antigenic disparities are still largely unknown. Here we report the identification of the gene encoding the human mHag HA-2 as a previously unknown member of the class I myosin family, which we have designated MYO1G. The gene is located on the short arm of chromosome 7. Expression of this gene is limited to cells of hemopoietic origin, in keeping with the previously defined tissue expression of the HA-2 Ag. RT-PCR amplification of MYO1G from different individuals led to the identification of two genetic variants, designated MYO1G(V) and MYO1G(M). The former encodes the peptide sequence previously shown to be the HA-2 epitope (YIGEVLVSV), whereas the latter shows a single amino acid change in this peptide (YIGEVLVSM). This change has only a modest effect on peptide binding to the class I MHC-restricted element HLA-A*0201, and a minimal impact on recognition by T cells when added exogenously to target cells. Nonetheless, as detected using either T cells or mass spectrometry, this amino acid change results in a failure of the latter peptide to be presented at the surface of cells that express MYO1G(M) endogenously. These studies have thus identified a new mHag-encoding gene, and thereby provide additional information about both the genetic origins of human mHag as well as the underlying basis of an Ag-positive vs Ag-negative state.
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Affiliation(s)
- R A Pierce
- Department of Microbiology and Carter Immunology Center, University of Virginia, Charlottesville, VA 22908, USA
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11
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Harnpicharnchai P, Jakovljevic J, Horsey E, Miles T, Roman J, Rout M, Meagher D, Imai B, Guo Y, Brame CJ, Shabanowitz J, Hunt DF, Woolford JL. Composition and functional characterization of yeast 66S ribosome assembly intermediates. Mol Cell 2001; 8:505-15. [PMID: 11583614 DOI: 10.1016/s1097-2765(01)00344-6] [Citation(s) in RCA: 262] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The pathway and complete collection of factors that orchestrate ribosome assembly are not clear. To address these problems, we affinity purified yeast preribosomal particles containing the nucleolar protein Nop7p and developed means to separate their components. Nop7p is associated primarily with 66S preribosomes containing either 27SB or 25.5S plus 7S pre-rRNAs. Copurifying proteins identified by mass spectrometry include ribosomal proteins, nonribosomal proteins previously implicated in 60S ribosome biogenesis, and proteins not known to be involved in ribosome production. Analysis of strains mutant for eight of these proteins not previously implicated in ribosome biogenesis showed that they do participate in this pathway. These results demonstrate that proteomic approaches in concert with genetic tools provide powerful means to purify and characterize ribosome assembly intermediates.
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Affiliation(s)
- P Harnpicharnchai
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA
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12
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Luckey CJ, Marto JA, Partridge M, Hall E, White FM, Lippolis JD, Shabanowitz J, Hunt DF, Engelhard VH. Differences in the expression of human class I MHC alleles and their associated peptides in the presence of proteasome inhibitors. J Immunol 2001; 167:1212-21. [PMID: 11466336 DOI: 10.4049/jimmunol.167.3.1212] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We have studied the contributions of proteasome inhibitor-sensitive and -insensitive proteases to the generation of class I MHC-associated peptides. The cell surface expression of 13 different human class I MHC alleles was inhibited by as much as 90% or as little as 40% when cells were incubated with saturating concentrations of three different proteasome inhibitors. Inhibitor-resistant class I MHC expression was not due to TAP-independent expression or preexisting internal stores of peptides. Furthermore, it did not correlate with the amount or specificity of residual proteasome activity as determined in in vitro proteolysis assays and was not augmented by simultaneous incubation with multiple inhibitors. Mass spectrometry was used to directly characterize the peptides expressed in the presence and absence of proteasome inhibitors. The number of peptide species detected correlated with the levels of class I detected by flow cytometry. Thus, for many alleles, a significant proportion of associated peptide species continue to be generated in the presence of saturating levels of proteasome inhibitors. Comparison of the peptide-binding motifs of inhibitor-sensitive and -resistant class I alleles further suggested that inhibitor-resistant proteolytic activities display a wide diversity of cleavage specificities, including a trypsin-like activity. Sequence analysis demonstrated that inhibitor-resistant peptides contain diverse carboxyl termini and are derived from protein substrates dispersed throughout the cell. The possible contributions of inhibitor-resistant proteasome activities and nonproteasomal proteases residing in the cytosol to the peptide profiles associated with many class I MHC alleles are discussed.
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Affiliation(s)
- C J Luckey
- Department of Microbiology, Carter Immunology Center, University of Virginia Health Sciences Center, Charlottesville, VA 22908, USA
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13
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Strahl BD, Briggs SD, Brame CJ, Caldwell JA, Koh SS, Ma H, Cook RG, Shabanowitz J, Hunt DF, Stallcup MR, Allis CD. Methylation of histone H4 at arginine 3 occurs in vivo and is mediated by the nuclear receptor coactivator PRMT1. Curr Biol 2001; 11:996-1000. [PMID: 11448779 DOI: 10.1016/s0960-9822(01)00294-9] [Citation(s) in RCA: 339] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Posttranslational modifications of histone amino termini play an important role in modulating chromatin structure and function. Lysine methylation of histones has been well documented, and recently this modification has been linked to cellular processes involving gene transcription and heterochromatin assembly. However, the existence of arginine methylation on histones has remained unclear. Recent discoveries of protein arginine methyltransferases, CARM1 and PRMT1, as transcriptional coactivators for nuclear receptors suggest that histones may be physiological targets of these enzymes as part of a poorly defined transcriptional activation pathway. Here we show by using mass spectrometry that histone H4, isolated from asynchronously growing human 293T cells, is methylated at arginine 3 (Arg-3) in vivo. In support, a novel antibody directed against histone H4 methylated at Arg-3 independently demonstrates the in vivo occurrence of this modification and reveals that H4 Arg-3 methylation is highly conserved throughout eukaryotes. Finally, we show that PRMT1 is the major, if not exclusive, H4 Arg-3 methyltransfase in human 293T cells. These findings suggest a role for arginine methylation of histones in the transcription process.
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Affiliation(s)
- B D Strahl
- Department of Biochemistry and Molecular Genetics, University of Virginia Health Science Center, Charlottesville, VA 22908, USA
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14
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Nepom GT, Lippolis JD, White FM, Masewicz S, Marto JA, Herman A, Luckey CJ, Falk B, Shabanowitz J, Hunt DF, Engelhard VH, Nepom BS. Identification and modulation of a naturally processed T cell epitope from the diabetes-associated autoantigen human glutamic acid decarboxylase 65 (hGAD65). Proc Natl Acad Sci U S A 2001; 98:1763-8. [PMID: 11172025 PMCID: PMC29331 DOI: 10.1073/pnas.98.4.1763] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
T cell recognition of autoantigens is critical to progressive immune-mediated destruction of islet cells, which leads to autoimmune diabetes. We identified a naturally presented autoantigen from the human islet antigen glutamic acid decarboxylase, 65-kDa isoform (GAD65), by using a combination of chromatography and mass spectrometry of peptides bound by the type I diabetes (insulin-dependent diabetes mellitus, IDDM)-associated HLA-DR4 molecule. Peptides encompassing this epitope-stimulated GAD65-specific T cells from diabetic patients and a DR4-positive individual at high risk for developing IDDM. T cell responses were antagonized by altered peptide ligands containing single amino acid modifications. This direct identification and manipulation of GAD65 epitope recognition provides an approach toward dissection of the complex CD4(+) T cell response in IDDM.
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Affiliation(s)
- G T Nepom
- Virginia Mason Research Center and Department of Immunology, University of Washington School of Medicine, Seattle, WA 98101, USA.
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15
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Guimezanes A, Barrett-Wilt GA, Gulden-Thompson P, Shabanowitz J, Engelhard VH, Hunt DF, Schmitt-Verhulst AM, Engelhardt VH. Identification of endogenous peptides recognized by in vivo or in vitro generated alloreactive cytotoxic T lymphocytes: distinct characteristics correlated with CD8 dependence. Eur J Immunol 2001; 31:421-32. [PMID: 11180106 DOI: 10.1002/1521-4141(200102)31:2<421::aid-immu421>3.0.co;2-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We studied the molecular basis for CD8 independence of in vivo generated (BM3.3) versus CD8 dependence of in vitro sensitized (KB5.C20/Des) alloreactive H-2K(b)-specific cytotoxic T lymphocytes (CTL). Using microcapillary high-performance liquid chromatography fractionation of H-2K(b) eluates, mass spectrometry and CTL reconstitution assays, we determined that BM3.3 and KB5.C20 recognize, respectively, a single peptide (pBM1) expressed on 8,000 H-2K(b) molecules per allogeneic cell, and three distinct peptides (pKB1, 2, 3), each expressed on around 200 H-2K(b) molecules per allogeneic cell. CD8 (in)dependence was intrinsic to the respective TCR/H-2K(b)-peptide interactions. KB5.C20 and BM3.3 TCR illustrate the correlation that appears to exist between CD8 dependence/low affinity and in vitro sensitization as opposed to low dependency on CD8 and high TCR affinity observed after in vivo sensitization. The results suggest that CD8-dependent alloreactive CTL obtained in vitro with high frequency correspond to low-affinity TCR from the MHC-biased TCR repertoire unpurged by negative selection and have implications for cellular immunotherapeutic approaches.
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Affiliation(s)
- A Guimezanes
- Centre d'Immunologie INSERM-CNRS de Marseille-Luminy, Marseille, France.
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16
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Lim KB, Walker CR, Guo L, Pellett S, Shabanowitz J, Hunt DF, Hewlett EL, Ludwig A, Goebel W, Welch RA, Hackett M. Escherichia coli alpha-hemolysin (HlyA) is heterogeneously acylated in vivo with 14-, 15-, and 17-carbon fatty acids. J Biol Chem 2000; 275:36698-702. [PMID: 10978310 DOI: 10.1074/jbc.c000544200] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
alpha-Hemolysin (HlyA) is a secreted protein virulence factor observed in certain uropathogenic strains of Escherichia coli. The active, mature form of HlyA is produced by posttranslational modification of the protoxin that is mediated by acyl carrier protein and an acyltransferase, HlyC. We have now shown using mass spectrometry that these modifications, when observed in protein isolated in vivo, consist of acylation at the epsilon-amino groups of two internal lysine residues, at positions 564 and 690, with saturated 14- (68%), 15- (26%), and 17- (6%) carbon amide-linked side chains. Thus, HlyA activated in vivo consists of a heterogeneous family of up to nine different covalent structures, and the substrate specificity of the HlyC acyltransferase appears to differ from that of the closely related CyaC acyltransferase expressed by Bordetella pertussis.
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Affiliation(s)
- K B Lim
- Department of Medicinal Chemistry, University of Washington, Seattle, Washington 98195, USA
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17
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Pestic-Dragovich L, Stojiljkovic L, Philimonenko AA, Nowak G, Ke Y, Settlage RE, Shabanowitz J, Hunt DF, Hozak P, de Lanerolle P. A myosin I isoform in the nucleus. Science 2000; 290:337-41. [PMID: 11030652 DOI: 10.1126/science.290.5490.337] [Citation(s) in RCA: 188] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
A nuclear isoform of myosin I beta that contains a unique 16-amino acid amino-terminal extension has been identified. An affinity-purified antibody to the 16-amino acid peptide demonstrated nuclear staining. Confocal and electron microscopy revealed that nuclear myosin I beta colocalized with RNA polymerase II in an alpha-amanitin- and actinomycin D-sensitive manner. The antibody coimmunoprecipitated RNA polymerase II and blocked in vitro RNA synthesis. This isoform of myosin I beta appears to be in a complex with RNA polymerase II and may affect transcription.
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Affiliation(s)
- L Pestic-Dragovich
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL 60612, USA
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18
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Martin SE, Shabanowitz J, Hunt DF, Marto JA. Subfemtomole MS and MS/MS peptide sequence analysis using nano-HPLC micro-ESI fourier transform ion cyclotron resonance mass spectrometry. Anal Chem 2000; 72:4266-74. [PMID: 11008759 DOI: 10.1021/ac000497v] [Citation(s) in RCA: 243] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Subfemtomole peptide sequence analysis has been achieved using microcapillary HPLC columns, with integrated nanoelectrospray emitters, coupled directly to a Fourier transform ion cyclotron resonance mass spectrometer. Accurate mass (+/-0.010 Da) peptide maps are generated from a standard six-protein digest mixture, whose principle components span a concentration dynamic range of 1000:1. Iterative searches against approximately 189000 entries in the OWL database readily identify each protein, with high sequence coverage (20-60%), from as little as 10 amol loaded on-column. In addition, a simple variable-flow HPLC apparatus provides for on-line tandem mass spectrometric analysis of tryptic peptides at the 400-amol level. MS/MS data are searched against approximately 280000 entries in a nonredundant protein database using SEQUEST. Accurate precursor and product ion mass information readily identifies primary amino acid sequences differing by asparagine vs aspartic acid (deltam = 0.98 Da) and glutamine vs lysine (deltam = 0.036 Da).
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Affiliation(s)
- S E Martin
- Department of Chemistry, University of Virginia, Charlottesville 22904-4319, USA
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19
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Crotzer VL, Christian RE, Brooks JM, Shabanowitz J, Settlage RE, Marto JA, White FM, Rickinson AB, Hunt DF, Engelhard VH. Immunodominance among EBV-derived epitopes restricted by HLA-B27 does not correlate with epitope abundance in EBV-transformed B-lymphoblastoid cell lines. J Immunol 2000; 164:6120-9. [PMID: 10843661 DOI: 10.4049/jimmunol.164.12.6120] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Using synthetic peptides, the HLA-B27-restricted CTL response to EBV in asymptomatic virus carriers has been mapped to four epitope regions in EBV latent cycle Ags. One of these peptide-defined epitopes (RRIYDLIEL) tends to be immunodominant and is recognized in the context of all three B27 subtypes studied, B*2702, B*2704, and B*2705. The other peptide-defined epitopes induce responses only in the context of one subtype, the immunogenic combinations being RRARSLSAERY/B*2702, RRRWRRLTV/B*2704, and FRKAQIQGL/B*2705. We used immunoaffinity chromatography to isolate the naturally presented viral peptides associated with these MHC class I molecules on the surface of EBV-transformed B-LCL. Using CTL reconstitution assays in conjunction with mass spectrometry, we established that the naturally processed and presented peptides are identical with the previously identified synthetic sequences. Despite the subtype-specific immunogenicity of three of the four epitopes, all four epitope peptides were found in association with each of the three different HLA-B27 subtypes. Indeed, those peptides that failed to induce a response in the context of a particular HLA-B27 subtype were frequently presented at greater abundance by that subtype than were the immunogenic peptides. Furthermore, among the peptides that did induce a response, immunodominance did not correlate with epitope abundance; in fact the immunodominant RRIYDLIEL epitope was least abundant, being present at less than one copy per cell. The relationship of this unexpected finding to the persistence of EBV is discussed.
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Affiliation(s)
- V L Crotzer
- Department of Microbiology and the Carter Immunology Center, University of Virginia, Charlottesville 22908, USA
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20
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Abstract
The objectives of this study were threefold: (i) assess immunogenicity of donor plasma proteins following hepatic xenotransplantation, (ii) identify potential immunogens, and (iii) consider the implications of antibody formation against these plasma proteins in xenograft survival. We studied liver and heart xenografts in a concordant combination, hamster to rat. All grafts were examined at necropsy for evidence of rat immunoglobulin G (IgG) deposition. Cardiac xenografts were placed in recipients who had, or had not, been sensitized with hamster serum. Hepatic xenografts were placed in naive recipients to see if antibodies to hamster serum proteins could be eluted from the rejecting organ. Sera of immunized rats were examined for the presence of anti-hamster antibodies by immunoelectrophoresis and by Western blotting following sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) separation of hamster serum. Antibodies in sera of immunized rats were compared with those eluted from rejecting livers. Candidate antigens were identified by tandem mass spectrometry, sequence analysis, and reference to protein databases. Results showed that sera of immunized rats recognized a minimum of four different antigens in hamster serum by immunoelectrophoresis, and a minimum of seven by the more sensitive SDS-PAGE Western blot. IgG eluted from rejecting livers bound three of seven candidate antigens recognized by sera of the immunized animals. Sequence analysis searches revealed proteinase inhibitors in each of the three SDS-PAGE bands common to the above samples. All of these candidate proteinase inhibitor immunogens share a common catabolic fate, uptake via the lipoprotein-related protein (LRP/alpha 2-macroglobulin receptor (CD91). Sensitization to hamster serum proteins hastened cardiac xenograft rejection in 30-50% of recipients (depending on sensitization protocol). Vascular deposition of rat IgG occurred in all rejecting xenografts. Antibody binding to proteinase inhibitors could disturb their functional activity and contribute to the pathogenesis of delayed xenograft rejection.
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Affiliation(s)
- S Celli
- Department of Surgery, University of Pittsburgh Transplant Institute, PA, USA.
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21
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Huberman A, Aguilar MB, Navarro-Quiroga I, Ramos L, Fernández I, White FM, Hunt DF, Shabanowitz J. A hyperglycemic peptide hormone from the Caribbean shrimp Penaeus (litopenaeus) schmitti. Peptides 2000; 21:331-8. [PMID: 10793213 DOI: 10.1016/s0196-9781(00)00155-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
From a crude extract of the sinus glands of the shrimp Penaeus (litopenaeus) schmitti a peptide with hyperglycemic activity in a homologous bioassay was isolated and characterized by a combination of automatic Edman degradation, enzymatic digestions, TLC of dansyl-amino acids, and mass spectrometry. Its M(r) is 8359.4 Da by MS, which coincides with the deduced sequence. Its N-terminus is free and its C-terminus is amidated. It has 6 Cys residues in conserved positions compared with other known CHHs. This is the first sinus gland hormone from an Atlantic Ocean shrimp characterized to date. It has a remarkable 90% sequence similarity to the Indo-Pacific shrimp P. (marsupenaeus) japonicus Pej-VII hyperglycemic hormone.
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Affiliation(s)
- A Huberman
- Instituto Nacional de la Nutrición 'Salvador Zubirán,' Department of Biochemistry, Vasco de Quiroga 15, Tlalpan, Mexico City, Mexico.
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22
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Abstract
The objectives of this study were threefold: (i) assess immunogenicity of donor plasma proteins following hepatic xenotransplantation, (ii) identify potential immunogens, and (iii) consider the implications of antibody formation against these plasma proteins in xenograft survival. We studied liver and heart xenografts in a concordant combination, hamster to rat. All grafts were examined at necropsy for evidence of rat immunoglobulin G (IgG) deposition. Cardiac xenografts were placed in recipients who had, or had not, been sensitized with hamster serum. Hepatic xenografts were placed in naive recipients to see if antibodies to hamster serum proteins could be eluted from the rejecting organ. Sera of immunized rats were examined for the presence of anti-hamster antibodies by immunoelectrophoresis and by Western blotting following sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) separation of hamster serum. Antibodies in sera of immunized rats were compared with those eluted from rejecting livers. Candidate antigens were identified by tandem mass spectrometry, sequence analysis, and reference to protein databases. Results showed that sera of immunized rats recognized a minimum of four different antigens in hamster serum by immunoelectrophoresis, and a minimum of seven by the more sensitive SDS-PAGE Western blot. IgG eluted from rejecting livers bound three of seven candidate antigens recognized by sera of the immunized animals. Sequence analysis searches revealed proteinase inhibitors in each of the three SDS-PAGE bands common to the above samples. All of these candidate proteinase inhibitor immunogens share a common catabolic fate, uptake via the lipoprotein-related protein (LRP/alpha 2-macroglobulin receptor (CD91). Sensitization to hamster serum proteins hastened cardiac xenograft rejection in 30-50% of recipients (depending on sensitization protocol). Vascular deposition of rat IgG occurred in all rejecting xenografts. Antibody binding to proteinase inhibitors could disturb their functional activity and contribute to the pathogenesis of delayed xenograft rejection.
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Affiliation(s)
- S Celli
- Department of Surgery, University of Pittsburgh Transplant Institute, PA, USA.
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23
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Pierce RA, Field ED, den Haan JM, Caldwell JA, White FM, Marto JA, Wang W, Frost LM, Blokland E, Reinhardus C, Shabanowitz J, Hunt DF, Goulmy E, Engelhard VH. Cutting edge: the HLA-A*0101-restricted HY minor histocompatibility antigen originates from DFFRY and contains a cysteinylated cysteine residue as identified by a novel mass spectrometric technique. J Immunol 1999; 163:6360-4. [PMID: 10586024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
In this report, we describe the use of novel mass spectrometry instrumentation to identify a male-specific minor histocompatibility Ag restricted by HLA-A*0101 (A1-HY). This Ag has the sequence IVDC*LTEMY, where C* represents a cysteine disulfide bonded to a second cysteine residue. The core peptide sequence is found in the protein product of DFFRY, a Y chromosome gene not previously identified as the source of an HY Ag. The male-specific form of the peptide differs from its X chromosomal counterpart by the substitution of serine for the C* residue. Both peptides are expressed on the cell surface at 30 or fewer copies per cell. However, A1-HY-specific CTL recognize the DFFRY-derived peptide at a 1500-fold lower dose than the female homologue. Thus, these studies have identified a new source of HY epitopes and provide additional information about the influence of posttranslational modifications of class I-associated peptides on T cell recognition.
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Affiliation(s)
- R A Pierce
- Department of Microbiology, Beirne B. Carter Center for Immunology Research, University of Virginia, Charlottesville 22908, USA
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24
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Skipper JC, Gulden PH, Hendrickson RC, Harthun N, Caldwell JA, Shabanowitz J, Engelhard VH, Hunt DF, Slingluff CL. Mass-spectrometric evaluation of HLA-A*0201-associated peptides identifies dominant naturally processed forms of CTL epitopes from MART-1 and gp100. Int J Cancer 1999; 82:669-77. [PMID: 10417764 DOI: 10.1002/(sici)1097-0215(19990827)82:5<669::aid-ijc9>3.0.co;2-#] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Melanoma-reactive human cytotoxic T lymphocytes (CTLs) mediate tumor regression in vivo through specific recognition of MHC-associated peptide epitopes, many of which are encoded by the melanocytic tissue differentiation proteins gp100/Pme117 and MART-1/Melan-A. Vaccines using these peptides may induce protective or therapeutic immunity against melanoma. Rational design of such approaches is aided by a clear understanding of the identity of these antigenic peptides; however, most CTL epitopes described to date were identified indirectly. Especially where these peptides may be used in human clinical trials for the treatment or prevention of cancer, there is substantial need for direct evaluation of HLA-A*0201-associated peptides from MART-1 and gp100 that are naturally processed and presented. To that end, we have isolated peptides directly from HLA-A*0201 molecules of human melanoma cells and have determined that naturally processed epitopes for HLA-A*0201-restricted, melanoma-reactive CTLs include the nonamers MART-1(27-35) (AAGIGILTV), gp100(154-162) (KTWGQYWQV), gp100(209-217) (ITDQVPFSV) and gp100(280-288) (YLEPGPVTA) and the decamer gp100(476-485) (VLYRYGSFSV). Among these, the one that appears to be most abundant at the cell surface is gp100(154-162) (KTWGQYWQV). The others are among the less abundant peptides. HLA-A*0201-restricted CTLs from one melanoma patient who has survived metastatic disease recognized MART-1(27-35) (AAGIGILTV), gp100(280-288) (YLEPGPVTA) and gp100(154-162) (KTWGQYWQV) and were cross-reactive on longer peptides that contained these nonamer sequences. These peptides, identified by both an indirect genetic approach and by a direct peptide approach, can be used for tumor vaccine strategies with confidence that they are identical to the naturally processed peptide epitopes presented at the surface of melanoma cells in association with HLA-A*0201 molecules.
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Affiliation(s)
- J C Skipper
- Department of Microbiology, University of Virginia Health Sciences Center and Cancer Center, Charlottesville, VA, USA
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25
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Skipper JC, Gulden PH, Hendrickson RC, Harthun N, Caldwell JA, Shabanowitz J, Engelhard VH, Hunt DF, Slingluff CL. Mass-spectrometric evaluation of HLA-A*0201-associated peptides identifies dominant naturally processed forms of CTL epitopes from MART-1 and gp100. Int J Cancer 1999. [PMID: 10417764 DOI: 10.1002/(sici)1097-0215(19990827)82:5<669::aid-ijc9>3.0.co;2-#] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Melanoma-reactive human cytotoxic T lymphocytes (CTLs) mediate tumor regression in vivo through specific recognition of MHC-associated peptide epitopes, many of which are encoded by the melanocytic tissue differentiation proteins gp100/Pme117 and MART-1/Melan-A. Vaccines using these peptides may induce protective or therapeutic immunity against melanoma. Rational design of such approaches is aided by a clear understanding of the identity of these antigenic peptides; however, most CTL epitopes described to date were identified indirectly. Especially where these peptides may be used in human clinical trials for the treatment or prevention of cancer, there is substantial need for direct evaluation of HLA-A*0201-associated peptides from MART-1 and gp100 that are naturally processed and presented. To that end, we have isolated peptides directly from HLA-A*0201 molecules of human melanoma cells and have determined that naturally processed epitopes for HLA-A*0201-restricted, melanoma-reactive CTLs include the nonamers MART-1(27-35) (AAGIGILTV), gp100(154-162) (KTWGQYWQV), gp100(209-217) (ITDQVPFSV) and gp100(280-288) (YLEPGPVTA) and the decamer gp100(476-485) (VLYRYGSFSV). Among these, the one that appears to be most abundant at the cell surface is gp100(154-162) (KTWGQYWQV). The others are among the less abundant peptides. HLA-A*0201-restricted CTLs from one melanoma patient who has survived metastatic disease recognized MART-1(27-35) (AAGIGILTV), gp100(280-288) (YLEPGPVTA) and gp100(154-162) (KTWGQYWQV) and were cross-reactive on longer peptides that contained these nonamer sequences. These peptides, identified by both an indirect genetic approach and by a direct peptide approach, can be used for tumor vaccine strategies with confidence that they are identical to the naturally processed peptide epitopes presented at the surface of melanoma cells in association with HLA-A*0201 molecules.
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Affiliation(s)
- J C Skipper
- Department of Microbiology, University of Virginia Health Sciences Center and Cancer Center, Charlottesville, VA, USA
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26
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Osterlund T, Beussman DJ, Julenius K, Poon PH, Linse S, Shabanowitz J, Hunt DF, Schotz MC, Derewenda ZS, Holm C. Domain identification of hormone-sensitive lipase by circular dichroism and fluorescence spectroscopy, limited proteolysis, and mass spectrometry. J Biol Chem 1999; 274:15382-8. [PMID: 10336425 DOI: 10.1074/jbc.274.22.15382] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Structure-function relationship analyses of hormone-sensitive lipase (HSL) have suggested that this metabolically important enzyme consists of several functional and at least two structural domains (Osterlund, T., Danielsson, B., Degerman, E., Contreras, J. A., Edgren, G., Davis, R. C., Schotz, M. C., and Holm, C. (1996) Biochem. J. 319, 411-420; Contreras, J. A., Karlsson, M., Osterlund, T., Laurell, H., Svensson, A., and Holm, C. (1996) J. Biol. Chem. 271, 31426-31430). To analyze the structural domain composition of HSL in more detail, we applied biophysical methods. Denaturation of HSL was followed by circular dichroism measurements and fluorescence spectroscopy, revealing that the unfolding of HSL is a two-step event. Using limited proteolysis in combination with mass spectrometry, several proteolytic fragments of HSL were identified, including one corresponding exactly to the proposed N-terminal domain. Major cleavage sites were found in the predicted hinge region between the two domains and in the regulatory module of the C-terminal, catalytic domain. Analyses of a hinge region cleavage mutant and calculations of the hydropathic pattern of HSL further suggest that the hinge region and regulatory module are exposed parts of HSL. Together, these data support our previous hypothesis that HSL consists of two major structural domains, encoded by exons 1-4 and 5-9, respectively, of which the latter contains an exposed regulatory module outside the catalytic alpha/beta-hydrolase fold core.
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Affiliation(s)
- T Osterlund
- Department of Cell and Molecular Biology, Lund University, S-221 00 Lund, Sweden
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27
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Pieper R, Christian RE, Gonzales MI, Nishimura MI, Gupta G, Settlage RE, Shabanowitz J, Rosenberg SA, Hunt DF, Topalian SL. Biochemical identification of a mutated human melanoma antigen recognized by CD4(+) T cells. J Exp Med 1999; 189:757-66. [PMID: 10049939 PMCID: PMC2192954 DOI: 10.1084/jem.189.5.757] [Citation(s) in RCA: 122] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
CD4(+) T cells play a critical role in generating and maintaining immune responses against pathogens and alloantigens, and evidence suggests an important role for them in antitumor immunity as well. Although major histocompatibility complex class II-restricted human CD4(+) T cells with specific antitumor reactivities have been described, no standard method exists for cloning the recognized tumor-associated antigen (Ag). In this study, biochemical protein purification methods were used in conjunction with novel mass spectrometry sequencing techniques and molecular cloning to isolate a unique melanoma Ag recognized by a CD4(+) tumor-infiltrating lymphocyte (TIL) line. The HLA-DRbeta1*0101-restricted Ag was determined to be a mutated glycolytic enzyme, triosephosphate isomerase (TPI). A C to T mutation identified by cDNA sequencing caused a Thr to Ile conversion in TPI, which could be detected in a tryptic digest of tumor-derived TPI by mass spectrometry. The Thr to Ile conversion created a neoepitope whose T cell stimulatory activity was enhanced at least 5 logs compared with the wild-type peptide. Analysis of T cell recognition of serially truncated peptides suggested that the mutated amino acid residue was a T cell receptor contact. Defining human tumor Ag recognized by T helper cells may provide important clues to designing more effective immunotherapies for cancer.
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Affiliation(s)
- R Pieper
- Surgery Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
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28
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Abstract
A cardioactive peptide was isolated from extracts of whole heads of the southern armyworm, Spodoptera eridania. This peptide has the sequence ENFAVGCTPGYQRTADGRCKPTF (Mr = 2516.8), determined from both Edman sequencing and tandem mass spectrometry in combination with off-line micropreparative capillary liquid chromatography. This peptide, termed Spoer-CAP23, has excitatory effects on a semi-isolated heart from larval Manduca sexta, causing an inotropic effect at low concentrations of peptide and chronotropic and inotropic effects at high doses. The threshold concentration for stimulatory effects of the synthetic peptide on the semi-isolated heart was about 1 nM, suggesting a physiological role as a neuropeptide.
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Affiliation(s)
- K Furuya
- Genentech, Inc., South San Francisco, CA 94080, USA
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29
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Hogan KT, Eisinger DP, Cupp SB, Lekstrom KJ, Deacon DD, Shabanowitz J, Hunt DF, Engelhard VH, Slingluff CL, Ross MM. The peptide recognized by HLA-A68.2-restricted, squamous cell carcinoma of the lung-specific cytotoxic T lymphocytes is derived from a mutated elongation factor 2 gene. Cancer Res 1998; 58:5144-50. [PMID: 9823325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The identification of naturally processed tumor peptides that can stimulate a tumor-specific, CTL response is crucial to the development of a vaccine-based, immunotherapeutic approach to cancer treatment. One type of cancer in which a tumor-specific, CTL response has been observed is squamous cell carcinoma of the lung. In the system investigated here, the tumor-specific CTLs are HLA-A68.2 restricted. Immunoaffinity chromatography was used to isolate the HLA-A68.2 molecules from the tumor cell line, and peptide was eluted with acid from the HLA-A68.2 molecules and subjected to three rounds of separation by reversed phase-high performance liquid chromatography (RP-HPLC). To determine which fractions contained the peptide recognized by the tumor-specific CTLs, an aliquot of each RP-HPLC fraction was added to the autologous, B-lymphoblastoid cell line, and the cells were then tested as targets for tumor-specific CTLs. After the third round of RP-HPLC, mass spectrometry was used to sequence individual peptide candidates, and a peptide with a m/z of 497 was identified as the active peptide. Collision-activated dissociation of m/z 497 allowed identification of the peptide sequence as ETVSEQSNV. With the exception of a single amino acid difference (glutamic acid versus glutamine as the sixth position in the peptide), this peptide is identical to residues 581 to 589 of elongation factor 2. The PCR was used to amplify the elongation factor 2 gene in both the tumor cells and the autologous B cell line, and DNA sequencing of the products revealed the presence of a heterozygous mutation in the tumor cells that accounts for the difference between the two peptide sequences. Although a similar analysis did not reveal the presence of the mutation in three additional lung cell carcinomas, this does not rule out the possibility that a survey of a larger population of tumor cells would reveal the presence of the mutation at a low frequency. These results demonstrate the utility of this approach for identifying tumor-specific antigens that are the targets of a CTL response.
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Affiliation(s)
- K T Hogan
- Argonex Pharmaceuticals, Charlottesville, Virginia 22903, USA
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30
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Luckey CJ, King GM, Marto JA, Venketeswaran S, Maier BF, Crotzer VL, Colella TA, Shabanowitz J, Hunt DF, Engelhard VH. Proteasomes can either generate or destroy MHC class I epitopes: evidence for nonproteasomal epitope generation in the cytosol. J Immunol 1998; 161:112-21. [PMID: 9647214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Proteasomes have been implicated in the production of the majority of peptides that associate with MHC class I molecules. We used two different proteasome inhibitors, the peptide aldehyde N-acetyl-L-leucyl-L-leucyl-L-norleucinal (LLnL) and the highly specific inhibitor lactacystin, to examine the role of proteasomes in generating peptide epitopes associated with HLA-A*0201. Neither LLnL nor lactacystin was able to completely block the expression of the HLA-A*0201. Furthermore, the effects of LLnL and lactacystin on the expression of different categories of specific epitopes, TAP independent vs TAP dependent and derived from either cytosolic or membrane proteins, were assessed. As predicted, presentation of two TAP-dependent epitopes was blocked by LLnL and lactacystin, while a TAP-independent epitope that is processed in the endoplasmic reticulum was unaffected by either inhibitor. Surprisingly, both LLnL and lactacystin increased rather than inhibited the expression of a cytosolically transcribed and TAP-dependent peptide from the influenza A virus M1 protein. Mass spectrometric analyses of in vitro proteasome digests of a synthetic 24 mer containing this epitope revealed no digestion products of any length that included the intact epitope. Instead, the major species resulted from cleavage sites within the epitope. Although cleavage at these sites was inhibitable by LLnL and lactacystin, epitope-containing species were still not produced. We conclude that proteasomes may in some cases actually destroy epitopes that would otherwise be destined for presentation by class I molecules. These results suggest that some epitopes are generated by nonproteasomal proteases in the cytosol.
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Affiliation(s)
- C J Luckey
- Department of Microbiology, Beirne Carter Center for Immunology Research, University of Virginia, Charlottesville 22908, USA
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31
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Kittlesen DJ, Thompson LW, Gulden PH, Skipper JC, Colella TA, Shabanowitz J, Hunt DF, Engelhard VH, Slingluff CL, Shabanowitz JA. Human melanoma patients recognize an HLA-A1-restricted CTL epitope from tyrosinase containing two cysteine residues: implications for tumor vaccine development. J Immunol 1998; 160:2099-106. [PMID: 9498746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
To identify shared epitopes for melanoma-reactive CTL restricted by MHC molecules other than HLA-A*0201, six human melanoma patient CTL lines expressing HLA-A1 were screened for reactivity against the melanocyte differentiation proteins Pmel-17/gp100, MART-1/Melan-A, and tyrosinase, expressed via recombinant vaccinia virus vectors. CTL from five of the six patients recognized epitopes from tyrosinase, and recognition of HLA-A1+ target cells was strongly correlated with tyrosinase expression. Restriction by HLA-A1 was further demonstrated for two of those tyrosinase-reactive CTL lines. Screening of 119 synthetic tyrosinase peptides with the HLA-A1 binding motif demonstrated that nonamer, decamer, and dodecamer peptides containing the sequence KCDICTDEY (residues 243-251) all reconstituted the CTL epitope in vitro. Epitope reconstitution in vitro required high concentrations of these peptides, which was hypothesized to be a result of spontaneous modification of cysteine residues, interfering with MHC binding. Substitution of serine or alanine for the more N-terminal cysteine prevented modification at that residue and permitted target cell sensitization at peptide concentrations 2 to 3 orders of magnitude lower than that required for the wild-type peptide. Because spontaneous modification of sulfhydryl groups may also occur in vivo, tumor vaccines using this or other cysteine-containing peptides may be improved by amino acid substitutions at cysteine residues.
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Affiliation(s)
- D J Kittlesen
- Department of Surgery, The Beirne Carter Center for Immunology, University of Virginia, Charlottesville 22908, USA
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32
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den Haan JM, Meadows LM, Wang W, Pool J, Blokland E, Bishop TL, Reinhardus C, Shabanowitz J, Offringa R, Hunt DF, Engelhard VH, Goulmy E. The minor histocompatibility antigen HA-1: a diallelic gene with a single amino acid polymorphism. Science 1998; 279:1054-7. [PMID: 9461441 DOI: 10.1126/science.279.5353.1054] [Citation(s) in RCA: 347] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The minor histocompatibility antigen (mHag) HA-1 is the only known mHag for which mismatching is correlated with the development of severe graft versus host disease (GvHD) after human leukocyte antigen-identical bone marrow transplantation. HA-1 was found to be a nonapeptide derived from an allele of the KIAA0223 gene. The HA-1-negative allelic counterpart encoded by KIAA0223 had one amino acid difference from HA-1. Family analysis with HA-1 allele-specific polymerase chain reaction showed an exact correlation between this allelic polymorphism and the HA-1 phenotype. HA-1 allele typing of donor and recipient should improve donor selection and allow the determination of bone marrow transplantation recipients with high risk for HA-1-induced GvHD development.
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Affiliation(s)
- J M den Haan
- Department of Immunohematology and Bloodbank, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
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33
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Mosse CA, Meadows L, Luckey CJ, Kittlesen DJ, Huczko EL, Slingluff CL, Shabanowitz J, Hunt DF, Engelhard VH. The class I antigen-processing pathway for the membrane protein tyrosinase involves translation in the endoplasmic reticulum and processing in the cytosol. J Exp Med 1998; 187:37-48. [PMID: 9419209 PMCID: PMC2199193 DOI: 10.1084/jem.187.1.37] [Citation(s) in RCA: 101] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/1997] [Revised: 10/22/1997] [Indexed: 02/05/2023] Open
Abstract
Formation of major histocompatibility complex class I-associated peptides from membrane proteins has not been thoroughly investigated. We examined the processing of an HLA-A*0201-associated epitope, YMDGTMSQV, that is derived from the membrane protein tyrosinase by posttranslational conversion of the sequence YMNGTMSQV. Only YMDGTMSQV and not YMNGTMSQV was presented by HLA-A*0201 on cells expressing full-length tyrosinase, although both peptides have similar affinities for HLA-A*0201 and are transported by TAP. In contrast, translation of YMNGTMSQV in the cytosol, as a minigene or a larger fragment of tyrosinase, led to the presentation of the unconverted YMNGTMSQV. This was not due to overexpression leading to saturation of the processing/conversion machinery, since presentation of the converted peptide, YMDGTMSQV, was low or undetectable. Thus, presentation of unconverted peptide was associated with translation in the cytosol, suggesting that processing of the full-length tyrosinase occurs after translation in the endoplasmic reticulum. Nevertheless, presentation of YMDGTMSQV in cells expressing full-length tyrosinase was TAP (transporter associated with antigen processing) and proteasome dependent. After inhibition of proteasome activity, tyrosinase species could be detected in the cytosol. We propose that processing of tyrosinase involves translation in the endoplasmic reticulum, export of full-length tyrosinase to the cytosol, and retransport of converted peptides by TAP for association with HLA-A*0201.
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Affiliation(s)
- C A Mosse
- Department of Microbiology and the Beirne Carter Center for Immunology Research, University of Virginia, Charlottesville, Virginia 22904, USA
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Revett SP, King G, Shabanowitz J, Hunt DF, Hartman KL, Laue TM, Nelson DJ. Characterization of a helix-loop-helix (EF hand) motif of silver hake parvalbumin isoform B. Protein Sci 1997; 6:2397-408. [PMID: 9385642 PMCID: PMC2143578 DOI: 10.1002/pro.5560061113] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Parvalbumins are a class of calcium-binding proteins characterized by the presence of several helix-loop-helix (EF-hand) motifs. It is suspected that these proteins evolved via intragene duplication from a single EF-hand. Silver hake parvalbumin (SHPV) consists of three EF-type helix-loop-helix regions, two of which have the ability to bind calcium. The three helix-loop-helix motifs are designated AB, CD, and EF, respectively. In this study, native silver hake parvalbumin isoform B (SHPV-B) has been sequenced by mass spectrometry. The sequence indicates that this parvalbumin is a beta-lineage parvalbumin. SHPV-B was cleaved into two major fragments, consisting of the ABCD and EF regions of the native protein. The 33-amino acid EF fragment (residues 76-108), containing one of the calcium ion binding sites in native SHPV-B, has been isolated and studied for its structural characteristics, ability to bind divalent and trivalent cations, and for its propensity to undergo metal ion-induced self-association. The presence of Ca2+ does not induce significant secondary structure in the EF fragment. However, NMR and CD results indicate significant secondary structure promotion in the EF fragment in the presence of the higher charge-density trivalent cations. Sedimentation equilibrium analysis results show that the EF fragment exists in a monomer-dimer equilibrium when complexed with La3+.
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Affiliation(s)
- S P Revett
- Gustaf H. Carlson School of Chemistry, Clark University, Worcester, Massachusetts 01610, USA
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35
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Chinni SR, Falchetto R, Gercel-Taylor C, Shabanowitz J, Hunt DF, Taylor DD. Humoral immune responses to cathepsin D and glucose-regulated protein 78 in ovarian cancer patients. Clin Cancer Res 1997; 3:1557-64. [PMID: 9815843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Many cancer patients develop tumor-reactive immune responses against antigens that are either expressed on the surface of tumor cells or released from them into the peripheral circulation. In this study, tumor-reactive immunoglobulins, present in the sera of ovarian cancer patients, were used to identify commonly recognized tumor-associated antigens on ovarian tumor cells. Western immunoblot analysis of cellular proteins, obtained from UL-1 ovarian tumor cell line, demonstrated several commonly recognized immunoreactive proteins. Two of these proteins (Mr 32,000 and 71,000) were selected for further investigation. Cellular proteins isolated from normal human ovarian epithelia, in a similar fashion, failed to exhibit corresponding immunoreactivity to these proteins. As an additional control, sera from normal (nontumor-bearing) individuals failed to identify these proteins on Western immunoblots. Furthermore, the absorption of the ovarian cancer patients' sera with normal ovarian epithelial tissue did not remove the reactivity of these two proteins. The Mr 32,000 and 71,000 proteins were subsequently purified by reverse-phase high-performance liquid chromatography, separated by SDS-PAGE, transferred to the polyvinylidene difluoride membrane, and digested with trypsin. These resulting tryptic fragments were separated by microbore reverse-phase high-performance liquid chromatography, and selected fragments were sequenced by mass spectrometry. This sequence analysis identified the Mr 32,000 protein as cathepsin D and the Mr 71,000 as glucose-regulated protein 78 (member of the heat shock protein family). The identities of cathepsin D and glucose-regulated protein 78 were confirmed by Western blot analysis. Additionally, the presence of cathepsin D was demonstrated in association with immune complexes in vivo. Currently, the common antigenic epitopes of these proteins are being defined.
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MESH Headings
- Adenocarcinoma, Mucinous/blood
- Adenocarcinoma, Mucinous/immunology
- Adenocarcinoma, Mucinous/pathology
- Adenocarcinoma, Papillary/blood
- Adenocarcinoma, Papillary/immunology
- Adenocarcinoma, Papillary/pathology
- Aged
- Antibodies, Neoplasm/biosynthesis
- Antibodies, Neoplasm/blood
- Antibody Specificity
- Antigen-Antibody Complex/blood
- Antigens, Neoplasm/immunology
- Blotting, Western
- Carrier Proteins/immunology
- Carrier Proteins/isolation & purification
- Cathepsin D/immunology
- Cathepsin D/isolation & purification
- Chromatography, High Pressure Liquid
- Cystadenoma, Papillary/blood
- Cystadenoma, Papillary/immunology
- Cystadenoma, Papillary/pathology
- Endoplasmic Reticulum Chaperone BiP
- Epitopes/immunology
- Female
- Heat-Shock Proteins
- Humans
- Mass Spectrometry
- Middle Aged
- Molecular Chaperones/immunology
- Molecular Chaperones/isolation & purification
- Molecular Weight
- Ovarian Neoplasms/blood
- Ovarian Neoplasms/immunology
- Ovarian Neoplasms/pathology
- Peptide Fragments/chemistry
- Sequence Analysis
- Tumor Cells, Cultured
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Affiliation(s)
- S R Chinni
- Departments of Obstetrics and Gynecology and Biochemistry, University of Louisville School of Medicine, Louisville, Kentucky 40292, USA
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36
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Polanowska-Grabowska R, Simon CG, Falchetto R, Shabanowitz J, Hunt DF, Gear AR. Platelet adhesion to collagen under flow causes dissociation of a phosphoprotein complex of heat-shock proteins and protein phosphatase 1. Blood 1997; 90:1516-26. [PMID: 9269769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Phosphorylation/dephosphorylation events in human blood platelets were investigated during their adhesion to collagen under flow conditions. Using 32P-labeled platelets and one-dimensional gel electrophoresis, we found that adhesion to collagen mediated primarily by the alpha2beta1 integrin resulted in a strong dephosphorylation of several protein bands. Neither adhesion to polylysine nor thrombin-induced aggregation caused similar protein dephosphorylation. In addition, treatment with okadaic acid (OA), an inhibitor of serine/threonine protein phosphatases type 1 (PP1) and 2A (PP2A), caused significant inhibition of adhesion, suggesting that adhesion is regulated by OA-sensitive phosphatases. Recent studies indicate that phosphatases may be associated with the heat-shock proteins. Immunoprecipitations with antibodies against either the heat-shock cognate protein 70 (hsc70) or heat-shock protein 90 (hsp90) showed the presence of a phosphoprotein complex in 32P-labeled, resting human platelets. Antibody probing of this complex detected hsc70, hsp90, two isoforms of the catalytic subunit of PP1, PP1C alpha and PP1C delta, as well as the M regulatory subunit of PP1 (PP1M). OA, at concentrations that markedly blocked platelet adhesion to collagen, caused hyperphosphorylation of the hsc70 complex. In platelets adhering to collagen, hsc70 was completely dephosphorylated and hsp90, PP1 alpha, and PP1M were dissociated from the complex, suggesting involvement of heat-shock proteins and protein phosphatases in platelet adhesion.
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37
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Hu Q, Bazemore Walker CR, Girao C, Opferman JT, Sun J, Shabanowitz J, Hunt DF, Ashton-Rickardt PG. Specific recognition of thymic self-peptides induces the positive selection of cytotoxic T lymphocytes. Immunity 1997; 7:221-31. [PMID: 9285407 DOI: 10.1016/s1074-7613(00)80525-7] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
To understand how thymic selection gives rise to T cells that are capable of major histocompatibility complex (MHC)-restricted recognition of antigen but are tolerant of self, we directly examined how peptide/MHC ligands expressed on thymic epithelial cells trigger the positive selection of immature thymocytes. We demonstrate that abundant self-peptides, purified from the H-2D(b) molecules of thymic epithelial cells, are specifically recognized during the positive selection of CD8+ T cells, implying that positive selection generates a repertoire of T cells that is weakly self-reactive. We also found that this recognition is somewhat cross-reactive, thereby providing an explanation for how the specific recognition of a limited repertoire of thymic self-peptides can select a diverse repertoire of T cells.
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MESH Headings
- Animals
- Autoantigens/immunology
- Autoantigens/isolation & purification
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/metabolism
- Cell Differentiation/immunology
- Cell Line
- Cytotoxicity, Immunologic
- Epithelium/immunology
- Female
- Fetus
- Lymphocyte Activation
- Lymphocytic choriomeningitis virus/immunology
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Mice, Transgenic
- Organ Culture Techniques
- Peptide Fragments/immunology
- Peptide Fragments/isolation & purification
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Receptors, Antigen, T-Cell, alpha-beta/immunology
- T-Lymphocytes, Cytotoxic/immunology
- T-Lymphocytes, Cytotoxic/metabolism
- T-Lymphocytes, Cytotoxic/virology
- Thymus Gland/cytology
- Thymus Gland/immunology
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Affiliation(s)
- Q Hu
- Gwen Knapp Center for Lupus and Immunology Research, Department of Pathology, University of Chicago, Illinois 60637, USA
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38
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Wang W, Gulden PH, Pierce RA, Shabanowitz J, Man ST, Hunt DF, Engelhard VH, Shabanowitz JA. A naturally processed peptide presented by HLA-A*0201 is expressed at low abundance and recognized by an alloreactive CD8+ cytotoxic T cell with apparent high affinity. The Journal of Immunology 1997. [DOI: 10.4049/jimmunol.158.12.5797] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
In contrast to T cells that respond to peptides presented by self MHC molecules, alloreactive T cells recognize determinants expressed on nonself MHC molecules. Because current positive selection models suggest that T cell affinity toward a nonself MHC molecule would be lower than that toward a self MHC molecule, we previously proposed that vigorous alloreactive responses would be generated preferentially toward those antigenic peptide complexes presented at the highest density on the cell surface. The high abundance of two class I MHC-associated peptides that have been identified as allo- or xenoantigens is consistent with this hypothesis. We report here the identification of a naturally processed peptide YLDPAQQNL that is presented by HLA-A*0201 and recognized by an alloreactive T cell clone. This peptide appears to originate from an unknown member of the zinc finger proteins. Quantitation by mass spectrometry indicates that this peptide is present on the surface at 85 to 125 copies per cell, comparable with the density of several other epitopes presented by HLA-A*0201 to self MHC-restricted T cells. In addition, based on the affinity of the peptide for HLA-A*0201 and the half-maximal peptide concentration required for T cell sensitization, this alloreactive T cell appears to have an affinity similar to or higher than that of many self MHC-restricted T cells. These data suggest that allogeneic responses can be directed against antigenic determinants of low abundance and that recognition of alloreactive peptides is not limited by a lower affinity of T cells for nonself MHC molecules.
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Affiliation(s)
- W Wang
- Department of Microbiology and the Beirne Carter Center for Immunology Research, University of Virginia, Charlottesville 22901, USA
| | - P H Gulden
- Department of Microbiology and the Beirne Carter Center for Immunology Research, University of Virginia, Charlottesville 22901, USA
| | - R A Pierce
- Department of Microbiology and the Beirne Carter Center for Immunology Research, University of Virginia, Charlottesville 22901, USA
| | - J Shabanowitz
- Department of Microbiology and the Beirne Carter Center for Immunology Research, University of Virginia, Charlottesville 22901, USA
| | - S T Man
- Department of Microbiology and the Beirne Carter Center for Immunology Research, University of Virginia, Charlottesville 22901, USA
| | - D F Hunt
- Department of Microbiology and the Beirne Carter Center for Immunology Research, University of Virginia, Charlottesville 22901, USA
| | - V H Engelhard
- Department of Microbiology and the Beirne Carter Center for Immunology Research, University of Virginia, Charlottesville 22901, USA
| | - J A Shabanowitz
- Department of Microbiology and the Beirne Carter Center for Immunology Research, University of Virginia, Charlottesville 22901, USA
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39
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Wang W, Gulden PH, Pierce RA, Shabanowitz J, Man ST, Hunt DF, Engelhard VH, Shabanowitz JA. A naturally processed peptide presented by HLA-A*0201 is expressed at low abundance and recognized by an alloreactive CD8+ cytotoxic T cell with apparent high affinity. J Immunol 1997; 158:5797-804. [PMID: 9190931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
In contrast to T cells that respond to peptides presented by self MHC molecules, alloreactive T cells recognize determinants expressed on nonself MHC molecules. Because current positive selection models suggest that T cell affinity toward a nonself MHC molecule would be lower than that toward a self MHC molecule, we previously proposed that vigorous alloreactive responses would be generated preferentially toward those antigenic peptide complexes presented at the highest density on the cell surface. The high abundance of two class I MHC-associated peptides that have been identified as allo- or xenoantigens is consistent with this hypothesis. We report here the identification of a naturally processed peptide YLDPAQQNL that is presented by HLA-A*0201 and recognized by an alloreactive T cell clone. This peptide appears to originate from an unknown member of the zinc finger proteins. Quantitation by mass spectrometry indicates that this peptide is present on the surface at 85 to 125 copies per cell, comparable with the density of several other epitopes presented by HLA-A*0201 to self MHC-restricted T cells. In addition, based on the affinity of the peptide for HLA-A*0201 and the half-maximal peptide concentration required for T cell sensitization, this alloreactive T cell appears to have an affinity similar to or higher than that of many self MHC-restricted T cells. These data suggest that allogeneic responses can be directed against antigenic determinants of low abundance and that recognition of alloreactive peptides is not limited by a lower affinity of T cells for nonself MHC molecules.
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Affiliation(s)
- W Wang
- Department of Microbiology and the Beirne Carter Center for Immunology Research, University of Virginia, Charlottesville 22901, USA
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40
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Hungerford JE, Hoeffler JP, Bowers CW, Dahm LM, Falchetto R, Shabanowitz J, Hunt DF, Little CD. Identification of a novel marker for primordial smooth muscle and its differential expression pattern in contractile vs noncontractile cells. J Cell Biol 1997; 137:925-37. [PMID: 9151694 PMCID: PMC2139835 DOI: 10.1083/jcb.137.4.925] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The assembly of the vessel wall from its cellular and extracellular matrix components is an essential event in embryogenesis. Recently, we used the descending aorta of the embryonic quail to define the morphological events that initiate the formation of a multilayered vessel wall from a nascent endothelial cell tube (Hungerford, J.E., G.K. Owens, W.S. Argraves, and C.D. Little. 1996. Dev. Biol. 178:375-392). We generated an mAb, 1E12, that specifically labels smooth muscle cells from the early stages of development to adulthood. The goal of our present study was to characterize further the 1E12 antigen using both cytological and biochemical methods. The 1E12 antigen colocalizes with the actin cytoskeleton in smooth muscle cells grown on planar substrates in vitro; in contrast, embryonic vascular smooth muscle cells in situ contain 1E12 antigen that is distributed in threadlike filaments and in cytoplasmic rosette-like patterns. Initial biochemical analysis shows that the 1E12 mAb recognizes a protein, Mr = 100,000, in lysates of adult avian gizzard. An additional polypeptide band, Mr = 40,000, is also recognized in preparations of lysate, when stronger extraction conditions are used. We have identified the 100-kD polypeptide as smooth muscle alpha-actinin by tandem mass spectroscopy analysis. The 1E12 antibody is an IgM isotype. To prepare a more convenient 1E12 immunoreagent, we constructed a single chain antibody (sFv) using recombinant protein technology. The sFv recognizes a single 100-kD protein in gizzard lysates. Additionally, the recombinant antibody recognizes purified smooth muscle alpha-actinin. Our results suggest that the 1E12 antigen is a member of the alpha-actinin family of cytoskeletal proteins; furthermore, the onset of its expression defines a primordial cell restricted to the smooth muscle lineage.
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Affiliation(s)
- J E Hungerford
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville 22908, USA
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41
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Laney EL, Shabanowitz J, King G, Hunt DF, Nelson DJ. The isolation of parvalbumin isoforms from the tail muscle of the American alligator (Alligator mississipiensis). J Inorg Biochem 1997; 66:67-76. [PMID: 9076974 DOI: 10.1016/s0162-0134(96)00187-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Multiple parvalbumin isoforms have been detected in the tail (skeletal) muscle of the American alligator (Alligator mississipiensis). One of these isoforms (APV-1) has been highly purified and partially characterized. Protein purification involved mainly gel filtration and anion exchange chromatography, and characterization included gel electrophoresis, amino acid composition analysis, metal ion analysis, MALDI-TOF and ESI mass spectrometry, ultraviolet and fluorescence spectroscopy, and one- and two-dimensional 500 MHz proton NMR spectroscopy. The alligator isoforms are rich in phenylalanine and deficient in the other aromatic residues as is typical for parvalbumins. In fact, the one highly purified isoform that forms the basis of this study has only phenyl-alanine as an aromatic residue. Ion exchange chromatography further indicates that this isoform has a relatively high isoelectric point (pl approximately 5.0), indicating that it is an alpha-lineage parvalbumin. This alligator parvalbumin isoform is unusual in that it has an atypically high Ca2+ content (almost 3.0 mole of Ca2+ per mole of protein) following purification, a fact supported by terbium fluorescence titration experiments. Preliminary comparative analysis of the highly purified alligator parvalbumin isoform (in the Ca2-loaded state) by two-dimensional 1H-NMR (2D 1H TOCSY and 2D 1H NOESY) indicates that there is considerable similarity in structure between the alligator protein and a homologous protein obtained from the silver hake (a saltwater fish species).
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Affiliation(s)
- E L Laney
- Gustaf H. Carlson School of Chemistry, Clark University, Worcester, MA 01610, USA
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42
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Meadows L, Wang W, den Haan JM, Blokland E, Reinhardus C, Drijfhout JW, Shabanowitz J, Pierce R, Agulnik AI, Bishop CE, Hunt DF, Goulmy E, Engelhard VH. The HLA-A*0201-restricted H-Y antigen contains a posttranslationally modified cysteine that significantly affects T cell recognition. Immunity 1997; 6:273-81. [PMID: 9075928 DOI: 10.1016/s1074-7613(00)80330-1] [Citation(s) in RCA: 225] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A peptide recognized by two cytotoxic T cell clones specific for the human minor histocompatibility antigen H-Y and restricted by HLA-A*0201 was identified. This peptide originates from SMCY, as do two other H-Y epitopes, supporting the importance of this protein as a major source of H-Y determinants in mice and humans. In naturally processed peptides, T cells only recognize posttranslationally altered forms of this peptide that have undergone modification of a cysteine residue in the seventh position. One of these modifications involves attachment of a second cysteine residue via a disulfide bond. This modification has profound effects on T cell recognition and also occurs in other class I MHC-associated peptides, supporting its general importance as an immunological determinant.
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Affiliation(s)
- L Meadows
- Department of Chemistry, University of Virginia, Charlottesville 22901, USA
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43
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Dubey P, Hendrickson RC, Meredith SC, Siegel CT, Shabanowitz J, Skipper JC, Engelhard VH, Hunt DF, Schreiber H. The immunodominant antigen of an ultraviolet-induced regressor tumor is generated by a somatic point mutation in the DEAD box helicase p68. J Exp Med 1997; 185:695-705. [PMID: 9034148 PMCID: PMC2196148 DOI: 10.1084/jem.185.4.695] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/1996] [Revised: 12/13/1996] [Indexed: 02/03/2023] Open
Abstract
The genetic origins of CD8+ T cell-recognized unique antigens to which mice respond when immunized with syngeneic tumor cells are unknown. The ultraviolet light-induced murine tumor 8101 expresses an H-2Kb-restricted immunodominant antigen, A, that induces cytolytic CD8+ T cells in vivo A+ 8101 cells are rejected by naive mice while A- 8101 tumor cells grow. To identify the antigen H-2Kb molecules were immunoprecipitated from A+ 8101 cells and peptides were eluted by acid. The sensitizing peptide was isolated by sequential reverse-phase HPLC and sequenced using microcapillary HPLC-triple quadruple mass spectrometry. The peptide, SNFVFAGI, matched the sequence of the DEAD box protein p68 RNA helicase except for a single amino acid substitution, caused by a single nucleotide change. This mutation was somatic since fibroblasts from the mouse of tumor origin expressed the wild-type sequence. The amino acid substitution created an anchor for binding of the mutant peptide to H-2Kb. Our results are consistent with mutant p68 being responsible for rejection of the tumor. Several functions of p68, which include nucleolar assembly and inhibition of DNA unwinding, may be mediated through its IQ domain, which was altered by the mutation. This is the first description of a somatic tumor-specific mutation in the coding region of a nucleic acid helicase.
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Affiliation(s)
- P Dubey
- Department of Pathology, The University of Chicago, Illinois 60637, USA
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44
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Fiorillo MT, Meadows L, D'Amato M, Shabanowitz J, Hunt DF, Appella E, Sorrentino R. Susceptibility to ankylosing spondylitis correlates with the C-terminal residue of peptides presented by various HLA-B27 subtypes. Eur J Immunol 1997; 27:368-73. [PMID: 9045906 DOI: 10.1002/eji.1830270205] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Susceptibility to spondyloarthropaties is strongly associated with some HLA-B27 alleles. Evidence suggests a direct pathogenic role for the B27 molecules which possibly present an arthritogenic peptide to the T cells. If this hypothesis is true, B27 subtypes that differ structurally but are disease-associated ought to be capable of presenting such peptide(s), while non-disease-associated ones would not. We have recently described a B27 subtype, B*2709, and shown its absence in ankylosing spondylitis (AS) patients. Here, we show the elution and sequence of peptides from HLA-B*2709 molecules. Similar to other B27 subtypes, these peptides are mainly nonamers with an Arg at position P2. Comparison of the C-terminal anchors of peptides eluted from B*2702 and B*2705 with those eluted from B*2709 reveals that, while B*2702 and B*2705 have a broader specificity, B*2709 molecules appear to only accept C-terminal hydrophobic residues. A common feature shared by the two caucasoid AS-associated subtypes (B*2702 and B*2705) but different from B*2709, is the presence of a Tyr as peptide C-terminal anchor. The substitution of Val for Tyr at the C terminus in one of the eluted peptides greatly reduces the binding to B*2709 molecules. This finding suggests Tyr as a discriminative amino acid allowed at the C terminus of peptides bound to the AS-associated B27 subtypes, but not to those which are not associated with AS.
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Affiliation(s)
- M T Fiorillo
- Department of Cell Biology and Development, University of Rome La Sapienza, Italy
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45
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Hunt JG, Kasinsky HE, Elsey RM, Wright CL, Rice P, Bell JE, Sharp DJ, Kiss AJ, Hunt DF, Arnott DP, Russ MM, Shabanowitz J, Ausió J. Protamines of reptiles. J Biol Chem 1996; 271:23547-57. [PMID: 8798564 DOI: 10.1074/jbc.271.38.23547] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
We have characterized for the first time the complete primary structure of the main protamine components of the sperm from four reptiles: Chrysemys picta (turtle), Elaphe obsoleta (snake), Anolis carolinensis (lizard), and Alligator mississipiensis (crocodilian). These species were chosen to represent one of each of the main phylogenetic branches of this taxonomic group. Comparison of these protamine sequences with those already available from other vertebrate groups allows us to define properly the chemical consensus composition of protamines and provides a unique insight into their molecular evolution and classification.
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Affiliation(s)
- J G Hunt
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 3P6, Canada
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Niedermann G, King G, Butz S, Birsner U, Grimm R, Shabanowitz J, Hunt DF, Eichmann K. The proteolytic fragments generated by vertebrate proteasomes: structural relationships to major histocompatibility complex class I binding peptides. Proc Natl Acad Sci U S A 1996; 93:8572-7. [PMID: 8710912 PMCID: PMC38714 DOI: 10.1073/pnas.93.16.8572] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Proteasomes are involved in the proteolytic generation of major histocompatibility complex (MHC) class I epitopes but their exact role has not been elucidated. We used highly purified murine 20S proteasomes for digestion of synthetic 22-mer and 41/44-mer ovalbumin partial sequences encompassing either an immunodominant or a marginally immunogenic epitope. At various times, digests were analyzed by pool sequencing and by semiquantitative electrospray ionization mass spectrometry. Most dual cleavage fragments derived from 22-mer peptides were 7-10 amino acids long, with octa- and nonamers predominating. Digestion of 41/44-mer peptides initially revealed major cleavage sites spaced by two size ranges, 8 or 9 amino acids and 14 or 15 amino acids, followed by further degradation of the latter as well as of larger single cleavage fragments. The final size distribution was slightly broader than that of fragments derived from 22-mer peptides. The majority of peptide bonds were cleaved, albeit with vastly different efficiencies. This resulted in multiple overlapping proteolytic fragments including a limited number of abundant peptides. The immunodominant epitope was generated abundantly whereas only small amounts of the marginally immunogenic epitope were detected. The frequency distributions of amino acids flanking proteasomal cleavage sites are correlated to that reported for corresponding positions of MHC class I binding peptides. The results suggest that proteasomal degradation products may include fragments with structural properties similar to MHC class I binding peptides. Proteasomes may thus be involved in the final stages of proteolytic epitope generation, often without the need for downstream proteolytic events.
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Affiliation(s)
- G Niedermann
- Max-Planck-Institut für Immunbiologie, Freiburg, Germany
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47
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Gulden PH, Fischer P, Sherman NE, Wang W, Engelhard VH, Shabanowitz J, Hunt DF, Pamer EG. A Listeria monocytogenes pentapeptide is presented to cytolytic T lymphocytes by the H2-M3 MHC class Ib molecule. Immunity 1996; 5:73-9. [PMID: 8758896 DOI: 10.1016/s1074-7613(00)80311-8] [Citation(s) in RCA: 99] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Polymorphism of MHC class Ia molecules severely constrains vaccine development against intracellular pathogens. Antigen presentation by MHC class Ib molecules, which are generally conserved between different individuals, may circumvent this obstacle. Herein, we use tandem mass spectrometry to identify a Listeria monocytogenes pentapeptide antigen that is presented to T lymphocytes by the H2-M3 MHC class Ib molecule. The peptide contains N-formyl methionine at the N terminus and exclusively hydrophobic amino acids. Mice of the H-2 d, H-2 b,and H-2 k haplotypes respond to this peptide upon infection with Listeria monocytogenes. Identification of antigens presented by MHC class Ib molecules is feasible and may provide opportunities for relatively unrestricted vaccine development.
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Affiliation(s)
- P H Gulden
- Department of Chemistry, University of Virginia, Charlottesville 22901, USA
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48
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di Marzo Veronese F, Arnott D, Barnaba V, Loftus DJ, Sakaguchi K, Thompson CB, Salemi S, Mastroianni C, Sette A, Shabanowitz J, Hunt DF, Appella E. Autoreactive cytotoxic T lymphocytes in human immunodeficiency virus type 1-infected subjects. J Exp Med 1996; 183:2509-16. [PMID: 8676071 PMCID: PMC2192610 DOI: 10.1084/jem.183.6.2509] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
A subtractive analysis of peptides eluted from major histocompatibility complex (MHC) class I human histocompatibility leukocyte antigen (HLA)-A2.1 molecules purified from either human immunodeficiency virus type-1 (HIV-1)-infected or uninfected cells was performed using micro high-performance liquid chromatography and mass spectrometry. Three peptides unique to infected cells were identified and found to derive from a single protein, human vinculin, a structural protein not known to be involved in viral pathogenesis. Molecular and cytofluorometric analyses revealed vinculin mRNA and vinculin protein overexpression in B and T lymphocytes from HIV-1-infected individuals. Vinculin peptide-specific CTL activity was readily elicited from peripheral blood lymphocytes of the majority of HLA-A2.1+, HIV+ patients tested. Our observations suggest that atypical vinculin expression and MHC class I-mediated presentation of vinculin-derived peptides accompany HIV infection of lymphoid cells in vivo, with a resultant induction of antivinculin CTL in a significant portion of HIV+ (HLA-A2.1+) individuals.
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Affiliation(s)
- F di Marzo Veronese
- Laboratory of Tumor Cell Biology, National Institutes of Health, Bethesda, Maryland 20892, USA
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49
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Kingan T, Shabanowitz J, Hunt D, Witten J. Characterization of two myotrophic neuropeptides in the FMRFamide family from the segmental ganglia of the moth Manduca sexta: candidate neurohormones and neuromodulators. J Exp Biol 1996; 199:1095-104. [PMID: 9318917 DOI: 10.1242/jeb.199.5.1095] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We have characterized two new members of the FMRFamide family of neuropeptides from the segmental ganglia of the tobacco hornworm Manduca sexta. Levels of peptides in ganglia used for purification were enhanced by manipulating their exposure to the steroid molting hormones. Explants of ganglia were cultured in the low-level ecdysteroid environment of diapausing pupae shown previously to evoke accumulation of FMRFamide-like immunoreactivity (FLI). Sufficient material for sequencing was obtained from 180 explanted ganglia. Extracts of ganglia were fractionated using two reverse-phase liquid chromatography procedures, and the immunoreactive fractions were subjected to sequence analysis using electrospray mass spectrometry. The sequences of the two peptides were determined to be GNSFLRFamide and DPSFLRFamide. These peptides have been named MasFLRFamide II and MasFLRFamide III, respectively; the previously characterized M. sexta FLRFamide (pEDVVHSFLRFamide) has been renamed MasFLRFamide I. The three peptides show distinctive tissue and developmental distributions as determined from fractionated extracts of larval and adult central nervous system structures and neurohemal organs. In the retrocerebral corpora cardiaca/corpora allata, MasFLRFamide I was the predominant form, while in the segmental ganglia MasFLRFamides II and III predominated. Higher levels of MasFLRFamide I and II were found in the adult, whereas there was little apparent change in the level of MasFLRFamide III upon metamorphosis. Determinations of peptide levels in fractionated hemolymph of newly emerged moths revealed that levels of MasFLRFamide I and III could exceed 10 nmol l-1. The actions of the three peptides were tested on the moth ileum. MasFLRFamides II and III were found to be stimulatory. At 1 nmol l-1, these peptides induced robust increases in the rate of rhythmic longitudinal and peristaltic waves of contractions. In contrast, MasFLRFamide I was ineffective even at 20 nmol l-1. Thus, while all three peptides have the characteristics of neurohormones in M. sexta, the physiological findings show that the heptapeptide FLRFamides have properties distinct from those of the decapeptide.
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50
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Janssen I, Schoofs L, Spittaels K, Neven H, Vanden Broeck J, Devreese B, Van Beeumen J, Shabanowitz J, Hunt DF, De Loof A. Isolation of NEB-LFamide, a novel myotropic neuropeptide from the grey fleshfly. Mol Cell Endocrinol 1996; 117:157-65. [PMID: 8737375 DOI: 10.1016/0303-7207(95)03746-2] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
A methanolic extract of 350,000 adult grey fleshflies Neobellieria bullata, was prepared and screened for myotropic activity. After fractionation on the first column, all fractions were screened in two heterologous (Locusta oviduct and Leucophaea hindgut) and one homologous (Neobellieria hindgut) myotropic bioassay. We here report the purification of one fraction, which stimulates the contractions of the Locusta oviduct. Electrospray Mass Spectrometry of the peptide revealed a molecular mass of 1395.82. The primary structure has been determined as AYRKPPFNGSLF-amide. This novel peptide was designated Neb-LF-amide. This sequence is different from the other known myotropic peptides in insects. The threshold concentration of the synthetic peptide is 1 x 10(-7) M on the Locusta oviduct. On the hindgut of Neobellieria or Leucophaea, the synthetic peptide is not active. By use of a polyclonal antiserum raised against the synthetic peptide, immunoreactivity was localized in median neurosecretory cells in the pars intercerebralis of the fly brain, indicating that Neb-LF-amide is a neuropeptide.
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Affiliation(s)
- I Janssen
- Zoological Institute, Catholic University of Leuven, Belgium.
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