1
|
Synthesis and characterisation of novel glycoclusters based on cell penetrating heptakis(6-aminoethylamino-6-deoxy)-β-cyclodextrin. J INCL PHENOM MACRO 2010. [DOI: 10.1007/s10847-010-9840-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
2
|
Abronina PI, Galkin KI, Backinowsky LV, Grachev AA. Synthesis of a derivative of a pentasaccharide repeating unit of the O-antigenic polysaccharide of the bacterium Klebsiella pneumoniae O3 as a benzoylated 2-methoxycarbonylethyl thioglycoside. Russ Chem Bull 2010. [DOI: 10.1007/s11172-010-0033-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
3
|
Baía P, André JP, Geraldes CFGC, Martins JA, Merbach AE, Tóth É. Lanthanide(III) Chelates of DTPA Bis(amide) Glycoconjugates: Potential Imaging Agents Targeted at the Asyaloglycoprotein Receptor. Eur J Inorg Chem 2005. [DOI: 10.1002/ejic.200400766] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
4
|
Schottelius M, Poethko T, Herz M, Reubi JC, Kessler H, Schwaiger M, Wester HJ. First (18)F-labeled tracer suitable for routine clinical imaging of sst receptor-expressing tumors using positron emission tomography. Clin Cancer Res 2004; 10:3593-606. [PMID: 15173065 DOI: 10.1158/1078-0432.ccr-03-0359] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Despite excellent radionuclide characteristics, no (18)F-labeled peptides are available for quantitative peptide receptor mapping using positron emission tomography (PET) so far, mainly due to time-consuming multistep radiosyntheses with limited overall yields. A newly developed two-step chemoselective conjugation method allows rapid and high-yield [(18)F]fluorination of peptides via oxime formation and was applied for the synthesis of new (18)F-labeled carbohydrated Tyr(3)-octreotate (TOCA) analogs with optimized pharmacokinetics suitable for clinical routine somatostatin-receptor (sst) imaging. EXPERIMENTAL DESIGN (18)F-labeled glucose (Gluc-S-) and cellobiose (Cel-S-) derivatives of aminooxy-functionalized TOCA were synthesized via oxime formation with 4-[(18)F]fluorobenzaldehyde ([(18)F]FBOA-peptides). Both the in vitro internalization profile of Gluc-S-Dpr([(18)F]FBOA)TOCA and Cel-S-Dpr([(18)F]FBOA)TOCA in hsst(2)-expressing Chinese hamster ovary cells (dual tracer protocol) and their biodistribution in AR42J tumor-bearing mice were investigated and compared with two [(18)F]fluoropropionylated ([(18)F]FP) analogs, Gluc-Lys([(18)F]FP)TOCA and Gluc-S-Dpr([(18)F]FP)TOCA. RESULTS In contrast to [(18)F]FP-labeling (3 h), chemo-selective [(18)F]FBOA-formation (50 min) afforded the respective radiopeptides in high yields (65-85%). In vitro, Gluc-S-Dpr([(18)F]FBOA)TOCA and Cel-S-Dpr([(18)F]FBOA)-TOCA showed high internalization (139 +/- 2 and 163 +/- 8 of the reference [(125)I]Tyr(3)-octreotide, respectively), which was reflected by high tumor accumulation in vivo [21.8 +/- 1.4 and 24.0 +/- 2.5% of injected dose/g (1 h), respectively]. How-ever, only Cel-S-Dpr([(18)F]FBOA)TOCA and Gluc-S-Dpr([(18)F]FP)TOCA (tumor: 15.1 +/- 1.5% of injected dose/g) with its very low accumulation in all of the nontarget organs showed improved tumor:organ ratios compared with Gluc-Lys([(18)F]FP)TOCA. For Cel-S-Dpr([(18)F]FBOA)TOCA,tumor:organ ratios (1 h) were 42:1, 27:1, 15:1, 3:1, and 208:1 for blood, liver, intestine, kidney, and muscle, respectively. CONCLUSION Due to the fast and high-yield chemoselective radiofluorination strategy and to its excellent pharmacokinetics, Cel-S-Dpr([(18)F]FBOA)TOCA represents the first tracer suitable for routine clinical application in PET somatostatin receptor imaging.
Collapse
Affiliation(s)
- Margret Schottelius
- Nuklearmedizinische Klinik und Poliklinik, Klinikum rechts der Isar, Technische Universität München, München, Germany
| | | | | | | | | | | | | |
Collapse
|
5
|
Vichier-Guerre S, Lo-Man R, Huteau V, Dériaud E, Leclerc C, Bay S. Synthesis and immunological evaluation of an antitumor neoglycopeptide vaccine bearing a novel homoserine Tn antigen. Bioorg Med Chem Lett 2004; 14:3567-70. [PMID: 15177475 DOI: 10.1016/j.bmcl.2004.04.047] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2004] [Revised: 04/05/2004] [Accepted: 04/08/2004] [Indexed: 11/24/2022]
Abstract
As part of our program on Tn-specific anti-tumor immunotherapy, our aim was to vary the nature of the aglyconic part of the tumor-associated Tn antigen (alpha-d-GalNAc-Ser/Thr). This report describes the synthesis of Fmoc-hSer-(alpha-d-GalNAc)-OH (4) in 19% overall yield from protected aspartic acid. The building block 4 was incorporated as trimeric clusters into a glycopeptide vaccine [MAG:Tn(hSer)3-PV], using solid-phase peptide synthesis. When injected in mice, the resulting MAG induces a strong antibody response, which recognizes native tumor-associated antigens (TAA) at the surface of human tumor cells. This approach may be extended to the use of other nonnatural TAA in order to improve half-life of synthetic anti-cancer vaccines.
Collapse
Affiliation(s)
- Sophie Vichier-Guerre
- Unité de Chimie Organique URA CNRS 2128, Institut Pasteur, 28, rue du Dr Roux, 75724 Paris 15, France
| | | | | | | | | | | |
Collapse
|
6
|
Espuelas S, Haller P, Schuber F, Frisch B. Synthesis of an amphiphilic tetraantennary mannosyl conjugate and incorporation into liposome carriers. Bioorg Med Chem Lett 2003; 13:2557-60. [PMID: 12852965 DOI: 10.1016/s0960-894x(03)00472-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We have synthesized a novel conjugate (Man(4)K(3)DOG) composed of a tetramannosyl head group connected, via a polyethylene glycol spacer, to a lipid moiety. This amphiphilic molecule was easily incorporated into the bilayers of liposomes. As expected from the clustering effect, such multivalent mannose residues when exposed on the surface of the vesicles showed much higher binding affinity for Concanavalin A than their monomannosyl analogue. Mannosylated liposomes prepared with the tetravalent antenna could be promising carriers for e.g., loading dendritic cells with antigens for vaccination purposes.
Collapse
Affiliation(s)
- Socorro Espuelas
- Laboratoire de Chimie Bioorganique, UMR 7514 CNRS/ULP, Université Louis Pasteur, Faculté de Pharmacie, 74 route du Rhin, 67400-Illkirch, France
| | | | | | | |
Collapse
|
7
|
Mogemark M, Cirrito TP, Sjölin P, Unanue ER, Kihlberg J. Influence of saccharide size on the cellular immune response to glycopeptides. Org Biomol Chem 2003; 1:2063-9. [PMID: 12945896 DOI: 10.1039/b301747h] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Glycopeptides that bind to MHC molecules on antigen presenting cells may elicit carbohydrate selective T cells. In order to investigate how the cellular immune response depends on the size of the carbohydrate moiety, a trigalactosylated derivative of an immunogenic peptide from hen egg-white lysozyme (HEL52-61) was prepared. Synthesis was accomplished by assembly of an alpha-1,4-linked trigalactose peracetate which was coupled to Fmoc serine. After activation as a pentafluorophenyl ester the resulting building block was used in solid-phase synthesis In contrast to the corresponding mono- and digalactosylated derivatives of HEL52-61, the trigalactosylated HEL52-61 was not immunogenic. Somewhat surprisingly, this was found to be because the trigalactosyl derivative bound approximately two orders of magnitude weaker to I-Ak MHC molecules than the mono- and digalactosyl peptides. Our observation suggests an explanation for previous findings, which show that glycopeptides isolated from MHC molecules in nature usually carry small saccharides.
Collapse
Affiliation(s)
- Mickael Mogemark
- Organic Chemistry, Department of Chemistry, Umeå University, SE-901 87 Umeå, Sweden
| | | | | | | | | |
Collapse
|
8
|
Cudic M, Ertl HCJ, Otvos L. Synthesis, conformation and T-helper cell stimulation of an O-linked glycopeptide epitope containing extended carbohydrate side-chains. Bioorg Med Chem 2002; 10:3859-70. [PMID: 12413838 DOI: 10.1016/s0968-0896(02)00388-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
To answer the question whether or not T cells to immunodominant protein fragments recognize glycosylated antigens, we synthesized a series of glycopeptides corresponding to peptide 31D, a major T-helper cell epitope of the rabies virus nucleoprotein. Thr4 of the epitope is known to allow mono- or disaccharide side-chain substitutions in either alpha- or beta-anomeric configuration without interfering with MHC-binding. To model naturally occurring glycoprotein fragments that carry extended sugar chains, we prepared Fmoc-Ser/Thr-OPfp building blocks containing alpha- and beta-linked linear tri- and heptasaccharides. Peptide 31D was synthesized with the complex carbohydrates attached to Thr4, and the T-helper cell activity of the glycopeptides was determined. Addition of alpha-linked carbohydrates, that mimic most of the natural O-linked glycoproteins, resulted in a major drop in the T-cell stimulatory ability in a sugar length-dependent manner. In contrast, the cytosolic glycoprotein mimicking beta-linked glycopeptides retained their T-cell stimulatory activity, with the trisaccharide-containing analogue being almost as potent as the unglycosylated peptide. When the peptides were preincubated with diluted human serum, all peptides lost their ability to stimulate the 9C5.D8-H hybridoma. These findings indicated that (i) in contrast to cytosolic glycosylation, incorporation of long O-linked carbohydrates into T-helper cell epitopes abrogates the antigenicity of these protein fragments, and (ii) glycosylation is not a viable alternative to improve the immunogenic properties of subunit peptide vaccines. Glycosylation with all four carbohydrate moieties similarly destroyed the inducible alpha-helical structure of peptide 31D as detected by CD, indicating that the differences in the T-cell activity were not due to different peptide conformations.
Collapse
Affiliation(s)
- Mare Cudic
- The Wistar Institute, Philadelphia, PA 19104, USA
| | | | | |
Collapse
|
9
|
Mitchell SA, Pratt MR, Hruby VJ, Polt R. Solid-phase synthesis of O-linked glycopeptide analogues of enkephalin. J Org Chem 2001; 66:2327-42. [PMID: 11281773 DOI: 10.1021/jo005712m] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The synthesis of 18 N-alpha-FMOC-amino acid glycosides for solid-phase glycopeptide assembly is reported. The glycosides were synthesized either from the corresponding O'Donnell Schiff bases or from N-alpha-FMOC-amino protected serine or threonine and the appropriate glycosyl bromide using Hanessian's modification of the Koenigs-Knorr reaction. Reaction rates of D-glycosyl bromides (e.g., acetobromoglucose) with the L- and D-forms of serine and threonine are distinctly different and can be rationalized in terms of the steric interactions within the two types of diastereomeric transition states for the D/L and D/D reactant pairs. The N-alpha-FMOC-protected glycosides [monosaccharides Xyl, Glc, Gal, Man, GlcNAc, and GalNAc; disaccharides Gal-beta(1-4)-Glc (lactose), Glc-beta(1-4)-Glc (cellobiose), and Gal-alpha(1-6)-Glc (melibiose)] were incorporated into 22 enkephalin glycopeptide analogues. These peptide opiates bearing the pharmacophore H-Tyr-c[DCys-Gly-Phe-DCys]- were designed to probe the significance of the glycoside moiety and the carbohydrate-peptide linkage region in blood-brain barrier (BBB) transport, opiate receptor binding, and analgesia.
Collapse
Affiliation(s)
- S A Mitchell
- Department of Chemistry, The University of Arizona, Tucson, Arizona 85721, USA
| | | | | | | |
Collapse
|
10
|
Vichier-Guerre S, Lo-Man R, Bay S, Deriaud E, Nakada H, Leclerc C, Cantacuzène D. Short synthetic glycopeptides successfully induce antibody responses to carcinoma-associated Tn antigen. THE JOURNAL OF PEPTIDE RESEARCH : OFFICIAL JOURNAL OF THE AMERICAN PEPTIDE SOCIETY 2000; 55:173-80. [PMID: 10784033 DOI: 10.1034/j.1399-3011.2000.00167.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Glycopeptides containing a tumor-associated carbohydrate antigen (mono-, tri- or hexa-Tn antigen) as a B-cell epitope and a CD4+ T-cell epitope (PV: poliovirus or TT: tetanus toxin) were prepared for immunological studies. Several Tn antigen residues [FmocSer/Thr (alpha-GalNAc)-OH] were successively incorporated into the peptide sequence with unprotected carbohydrate groups. The tri- and hexa-Tn glycopeptides were recognized by MLS128, a Tn-specific monoclonal antibody. The position of the tri-Tn motif in the peptide sequence and the peptide backbone itself do not alter its antigenicity. As demonstrated by both ELISA and FACS analysis, the glycopeptides induced high titers of anti-Tn antibodies in mice, in the absence of a carrier molecule. In addition, the generated antibodies recognized the native Tn antigen on cancer cells. The antibody response obtained with a D-(Tn3)-PV glycopeptide containing three alpha-GalNAc-D-serine residues is similar that obtained with the Tn6-PV glycopeptide. These results demonstrate that short synthetic glycopeptides are able to induce anticancer antibody responses.
Collapse
|
11
|
Harth-Fritschy E, Dufour S, Si-Tahar M, Chignard M, Biberovic V, Cantacuzène D. RGDS glycosylated peptides as inhibitors of cell-attachment and platelet aggregation. THE JOURNAL OF PEPTIDE RESEARCH : OFFICIAL JOURNAL OF THE AMERICAN PEPTIDE SOCIETY 1998; 52:51-9. [PMID: 9716251 DOI: 10.1111/j.1399-3011.1998.tb00652.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Glycopeptides derived from the GRGDS sequence were synthesized to study the effect of the sugar residue on the activity of these peptides. The peptides were tested as inhibitors of cell adhesion to fibronectin and of platelet aggregation. The sugar moiety was found to reduce the biological activity of the parent compounds except for the cyclic derivatives P37 and P38 where the inhibition of platelet aggregation was increased. Some interesting differences were observed between the peptides bearing sugar residues with free hydroxyl groups and those with peracetylated sugars.
Collapse
Affiliation(s)
- E Harth-Fritschy
- Institut Pasteur, Département de Biochimie et Génétique Moléculaire, Paris, France
| | | | | | | | | | | |
Collapse
|
12
|
Reis CA, Sørensen T, Mandel U, David L, Mirgorodskaya E, Roepstorff P, Kihlberg J, Hansen JE, Clausen H. Development and characterization of an antibody directed to an alpha-N-acetyl-D-galactosamine glycosylated MUC2 peptide. Glycoconj J 1998; 15:51-62. [PMID: 9530956 DOI: 10.1023/a:1006939432665] [Citation(s) in RCA: 244] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
In an attempt to raise anti-Tn antibodies, an alpha-N-acetyl-D-galactosamine glycosylated peptide based on the tandem repeat of the intestinal mucin MUC2 was used as an immunogen. The MUC2 peptide (PTTTPISTTTMVTPTPTPTC) was glycosylated in vitro using concentrated alpha-N-acetylgalactosaminyltransferases activity from porcine submaxillary glands which resulted in the incorporation of 8-9 mol of Ga/NAc. Rabbits and mice developed specific anti-MUC2-GalNAc glycopeptide antibodies and no detectable anti-Tn antibodies. Anti-glycopeptide antibodies did not show reactivity with the unglycosylated MUC2 peptide or with other GalNAc glycosylated peptides. A mouse monoclonal antibody (PMH1) representative of the observed immune response was generated and its immunohistological reactivity analysed in normal tissues. PMH1 reacted similarly to other anti-MUC2 peptide antibodies. However, in some cells the staining was not restricted to the supranuclear area but extended to the entire cytoplasm. In addition, PMH1 reacted with purified colonic mucin by Western blot analysis suggesting that PMH1 reacted with some glycoforms of MUC2. The present work presents a useful approach for development of anti-mucin antibodies directed to different glycoforms of individual mucins.
Collapse
Affiliation(s)
- C A Reis
- School of Dentistry, Faculty of Health Sciences, Copenhagen, Denmark
| | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Harth-Fritschy E, Cantacuzène D. Esterification of 9-fluorenylmethoxycarbonyl-glycosylated serine and cysteine derivatives with an hydroxymethyl resin. THE JOURNAL OF PEPTIDE RESEARCH : OFFICIAL JOURNAL OF THE AMERICAN PEPTIDE SOCIETY 1997; 50:415-20. [PMID: 9440042 DOI: 10.1111/j.1399-3011.1997.tb01204.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Esterification of glycosylated serine and cysteine derivatives with a 4-alkoxybenzyl alcohol (Wang) resin is described. The classical methods of ester bond formation (symmetrical anhydride, 2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium tetrafluoroborate [TBTU]/4-dimethylaminopyridine [DMAP] with or without 1-hydroxybenzotriazole [HOBT], pentafluorophenyl [Pfp] esters gave high percentages of racemization of the glycosylated serine or cysteine residues. To reduce the D-amino acid content, we found that the best results were obtained with the highly efficient MSNT reagent (2,4,6-mesitylenesulfonyl-3-nitro-1,2,4-triazolide), which gave a high yield of substitution of the resin and the lowest percentage of racemization. A difference in behavior was observed between the two amino acids. The glycosylated cysteine derivative always gave lower racemization than the analogous glycosylated serine.
Collapse
Affiliation(s)
- E Harth-Fritschy
- Institut Pasteur, Département de Biochimie et Génétique Moléculaire, Paris, France
| | | |
Collapse
|
14
|
Kihlberg J, Elofsson M, Salvador LA. Direct synthesis of glycosylated amino acids from carbohydrate peracetates and Fmoc amino acids: solid-phase synthesis of biomedicinally interesting glycopeptides. Methods Enzymol 1997; 289:221-45. [PMID: 9353724 DOI: 10.1016/s0076-6879(97)89050-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
|
15
|
Michael K, Wittmann V, König W, Sandow J, Kessler H. S- and C-glycopeptide derivatives of an LH-RH agonist. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1996; 48:59-70. [PMID: 8844264 DOI: 10.1111/j.1399-3011.1996.tb01107.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The S- and C-glycosylated nonapeptides 1 and 2 were synthesized as analogs of the non-glycosylated LH-RH agonist buserelin (pGlu-His-Trp-Ser-Tyr-D-Ser(tBu)-Leu-Arg-Pro-NHEt) by segment condensation in solution. 1 and 2 differ from this peptide in the amino acid in position 6. In the first case (1), D-serine (tBu) is substituted by D-cysteine carrying a rhamnosyl residue, in the second case (2) D-alanine carrying a galactosyl moiety bound as C-glycoside is incorporated. The bioactivity of both glycopeptides as fertility drugs was determined from the dose dependent LH release in male rats. Additionally, in female rats the ovulation rate was assessed. As a result the analog 1 exhibits a similar biological activity as buserelin while analog 2 shows about 25% of this potency. Compared to buserelin the solubility of the analogs 1 and 2 in aqueous buffer is improved by more than two orders of magnitude due to the carbohydrate moieties.
Collapse
Affiliation(s)
- K Michael
- Institute for Organic Chemistry and Biochemistry, Technical University of Munich, Garching, Germany
| | | | | | | | | |
Collapse
|
16
|
Elofsson M, Walse B, Kihlberg J. Solid-phase synthesis and conformational studies of helper T cell immunogenic peptides that carry carbohydrate haptens linked to serine. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1996; 47:340-7. [PMID: 8791156 DOI: 10.1111/j.1399-3011.1996.tb01082.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
N alpha-Fmoc serine and its corresponding pentafluorophenyl ester were glycosylated with the 1,2-trans peracetates of the disaccharides galabiose and cellobiose. Complete stereoselectivity and 52-75% yields were obtained under boron trifluoride etherate promotion. Lower yields and loss of stereoselectivity were obtained when thioglycosides, trichloroacetimidates or glycosyl bromides were employed as glycosyl donors. The glycosylated building blocks were used in solid-phase synthesis of derivatives of a helper T cell immunogenic peptide consisting of amino acids 52-61 from hen-egg lysozyme. 1H-NMR spectroscopy in DMSO-d6 showed that the peptide moiety of the glycopeptides assumed random conformations which were not influenced by glycosylation at different positions.
Collapse
Affiliation(s)
- M Elofsson
- Center for Chemistry and Chemical Engineering, Lund Institute of Technology, Lund University, Sweden
| | | | | |
Collapse
|
17
|
Abdel-Motal UM, Berg L, Rosén A, Bengtsson M, Thorpe CJ, Kihlberg J, Dahmén J, Magnusson G, Karlsson KA, Jondal M. Immunization with glycosylated Kb-binding peptides generates carbohydrate-specific, unrestricted cytotoxic T cells. Eur J Immunol 1996; 26:544-51. [PMID: 8605919 DOI: 10.1002/eji.1830260307] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Cytotoxic T cells (CTL) recognize target proteins as short peptides presented by major histocompatibility complex (MHC) class I restriction elements. However, there is also evidence for peptide-independent T cell receptor (TCR) recognition of target proteins and non-protein structures. How such T cell responses are generated is presently unclear. We generated carbohydrate (CHO)-specific, MHC-unrestricted CTL responses by coupling di- and trisaccharides to Kb- or Db-binding peptides for direct immunization in mice. Four peptides and three CHO have been analyzed with the CHO either in terminal or central position on the carrier peptide. With two of these glycopeptides, with galabiose (Gal alpha 1-4Gal; Gal2) bound to a homocysteine (via an ethylene spacer arm) in position 4 or 6 in a vesicular stomatitis virus nucleoprotein-derived peptide (RGYVYQGL binding to Kb), CTL were generated which preferentially killed target cells treated with glycopeptide compared to those treated with the core peptide. Polyclonal CTL were also found to kill target cells expressing the same Gal2 epitope in a glycolipid. By fractionation of CTL, preliminary data indicate that glycopeptide-specific Kb-restricted CTL and unrestricted CHO-specific CTL belong to different T cell populations with regard to TCR expression. The results demonstrate that hapten-specific unrestricted CTL responses can be generated with MHC class I-binding carrier peptides. Different models that might explain the generation of such responses are discussed.
Collapse
Affiliation(s)
- U M Abdel-Motal
- Department of Medical Biochemistry and Microbiology, University of Gothenburg, Sweden
| | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Sjölin P, Elofsson M, Kihlberg J. Removal of Acyl Protective Groups from Glycopeptides: Base Does Not Epimerize Peptide Stereocenters, and beta-Elimination Is Slow. J Org Chem 1996; 61:560-565. [PMID: 11666975 DOI: 10.1021/jo951817r] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Epimerization of glycopeptide stereocenters and beta-elimination have been considered as important potential side reactions on deacylation of glycopeptides which have the carbohydrate moieties protected with O-acyl groups. Since no systematic investigation of these side reactions has been reported, a model acetylated, O-linked glycotripeptide and its three epimers at the alpha-carbon stereocenters were prepared. The model glycopeptide did not undergo any epimerization (<1%) or beta-elimination, as determined by (1)H NMR spectroscopy, under various conditions which are in common use for deacetylation of glycopeptides. Under more severe conditions, which are required for removal of O-benzoyl groups, beta-elimination occurred slowly and was accompanied by slight (<5%) epimerization. The surprisingly low tendency of glycopeptides to undergo base catalyzed epimerization and beta-elimination is most likely due to protection of the alpha-carbon stereocenters by deprotonation of the adjacent amide groups.
Collapse
Affiliation(s)
- Petter Sjölin
- Department of Organic Chemistry 2, Center for Chemistry and Chemical Engineering, The Lund Institute of Technology, Lund University, P.O. Box 124, S-221 00 Lund, Sweden
| | | | | |
Collapse
|
19
|
Abdel-Motal UM, Berg L, Bengtsson M, Dahmén J, Kihlberg J, Magnusson G, Nilsson U, Jondal M. Major histocompatibility complex class I binding glycopeptides for the estimation of 'empty' class I molecules. J Immunol Methods 1995; 188:21-31. [PMID: 8551035 DOI: 10.1016/0022-1759(96)82888-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Different forms of major histocompatibility complex (MHC) class I heavy chains are known to be expressed on the cell surface, including molecules which are functionally 'empty'. Direct peptide binding to cells is obvious during sensitization of target cells in vitro for cytotoxic T lymphocyte killing and 'empty' MHC-I molecules are comparatively abundant on TAP-1/2 peptide transporter mutant cells. In the present work we have estimated the fraction of 'empty' MHC class I molecules using glycosylated peptides and cellular staining with carbohydrate specific monoclonal antibodies. Synthetic Db and Kb binding peptides were coupled at different positions with different di- or trisaccharides, using different spacing between the carbohydrate and the peptide backbone. Binding of sugar specific mAbs was compared in ELISA and cellular assays. An optimal Db binding glycopeptide was used for comparative staining with anti-Db and anti-carbohydrate monoclonal antibodies to estimate fractions of 'empty' molecules on different T lymphoid cells. On activated normal T cells, a large fraction of Db molecules were found to be 'empty'. The functional role of such 'empty' MHC class I molecules on T cells is presently unclear. However, on antigen presenting cells they might participate in the antigen presentation process.
Collapse
Affiliation(s)
- U M Abdel-Motal
- Microbiology and Tumor Biology Center (MTC), Karolinska Institutet, Stockholm, Sweden
| | | | | | | | | | | | | | | |
Collapse
|
20
|
Brumeanu TD, Dehazya P, Wolf I, Bona CA. Enzymatically mediated, glycosidic conjugation of immunoglobulins with viral epitopes. J Immunol Methods 1995; 183:185-97. [PMID: 7541431 DOI: 10.1016/0022-1759(95)00092-o] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
We developed a novel enzymatic procedure to couple a peptide to the sugar moieties of immunoglobulins (Igs). The synthesis of the conjugates consists in galactose (Gal) oxidation of desialylated Igs followed by covalent attachment of the peptides with concurrent stabilization of the Schiff bases upon mild reduction. The peptide used in this study, corresponds to the amino acid residues 110-120 of hemagglutinin (HA) of PR8 A virus and is recognized by CD4 T helper cells in association with I-Ed class II major histocompatibility complex (MHC). The degree of coupling as determined by competitive inhibition of radioimmunoassay (IRIA) using FPLC purified conjugates was estimated at 11.4 peptides per IgG molecule. Coupling of HA110-120 peptide to the sugar moiety of various mouse and human Igs was confirmed by Western blot analysis developed with anti-HA110-120 antibodies. Complete detachment of the peptide from the conjugates by N-deglycosylation with PGNase F indicated a defined specificity of coupling HA peptide to the N-linked oligosaccharides of Igs. To facilitate quick release of the peptides from the conjugates into the lysosomal compartment of the antigen processing cells (APC) we introduced at the alpha amino terminus of the peptide (HAc110-120), a cleavage site for cathepsins (AAAL). The immunoglobulin-galactose-HAc110-120 conjugates (IGP) were able to activate HA110-120 specific T hybridoma cells as efficient as influenza PR8 A virus and 40-100-fold higher than the synthetic peptide itself.
Collapse
Affiliation(s)
- T D Brumeanu
- Department of Microbiology, Mount Sinai School of Medicine, New York, NY 10029, USA
| | | | | | | |
Collapse
|
21
|
Stereoselective phase transfer catalyzed syntheses of glycosyloxysuccinimides and their transformations into glycoprobes. Tetrahedron 1995. [DOI: 10.1016/0040-4020(95)00325-3] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
22
|
Preparation of building blocks for glycopeptide synthesis by glycosylation of Fmoc amino acids having unprotected carboxyl groups. Tetrahedron 1995. [DOI: 10.1016/0040-4020(95)00224-v] [Citation(s) in RCA: 82] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
23
|
|
24
|
Elofsson M, Broddefalk J, Ekberg T, Kihlberg J. Synthesis of a water-soluble serine-based neoglycolipid which can be covalently linked to solid phases. Carbohydr Res 1994; 258:123-33. [PMID: 8039173 DOI: 10.1016/0008-6215(94)84080-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
N alpha-Fmoc-serine pentafluorophenyl ester was glycosylated with perbenzoylated lactosyl bromide. The resulting product was coupled to a resin functionalized with 6-aminohexanoic acid and then N alpha-acylated to give a serine-based analogue of lactosylceramide. The water-soluble neoglycolipid was covalently linked to microtiter plates via its carboxyl group and was recognized by a lactose-binding lectin in an ELISA.
Collapse
Affiliation(s)
- M Elofsson
- Chemical Center, University of Lund, Sweden
| | | | | | | |
Collapse
|