Skip to Content
Merck
  • Synthetic peptides reproducing tissue transglutaminase-gliadin complex neo-epitopes as probes for antibody detection in celiac disease patients' sera.

Synthetic peptides reproducing tissue transglutaminase-gliadin complex neo-epitopes as probes for antibody detection in celiac disease patients' sera.

Journal of medicinal chemistry (2015-01-15)
Margherita Di Pisa, Simona Pascarella, Mario Scrima, Giuseppina Sabatino, Feliciana Real-Fernández, Mario Chelli, Daniela Renzi, Antonio Calabrò, Anna Maria D'Ursi, Anna Maria Papini, Paolo Rovero
ABSTRACT

Celiac disease (CD) patients usually present high levels of circulating IgA antibodies directed to different antigens, in particular tissue transglutaminase (tTG), gliadin (Glia), and endomysium. A series of synthetic peptide constructs containing cross-linked tTG and Glia deamidated peptides have been synthesized. Peptides were tested in enzyme-linked immunosorbent assays against celiac disease patients' sera versus normal blood donors, and their conformational features were evaluated by molecular modeling techniques. Four peptides were recognized as epitopes by autoantibodies (IgG class) circulating in CD patients' sera before gluten-free diet. The peptide II, containing Ac-tTG(553-564)-NH2 sequence cross-linked with deamidated Ac-α2-Glia(63-71)-NH2, was able to identify specific disease antibodies with a sensitivity of 50% and a specificity of 94.4%. Structural conformations of the linear fragments Ac-tTG(553-564)-NH2 and Ac-α2-Glia(63-71)-NH2 and the corresponding cross-linked peptide II were calculated by molecular modeling. Results showed that cross-linking is determinant to assume conformations, which are not accessible to the linear fragments.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Fmoc-Ser(Trt)-OH, ≥98.0%
Supelco
N,N-Dimethylformamide, analytical standard
Sigma-Aldrich
N,N-Dimethylformamide, anhydrous, 99.8%
Sigma-Aldrich
N,N-Dimethylformamide, for molecular biology, ≥99%
Supelco
Dimethylformamide, Pharmaceutical Secondary Standard; Certified Reference Material
Supelco
Residual Solvent - Acetonitrile, Pharmaceutical Secondary Standard; Certified Reference Material
Sigma-Aldrich
N,N-Dimethylformamide, ACS reagent, ≥99.8%
Sigma-Aldrich
N,N-Dimethylformamide, biotech. grade, ≥99.9%
Sigma-Aldrich
N,N-Dimethylformamide, ReagentPlus®, ≥99%
Sigma-Aldrich
N,N-Dimethylformamide, puriss. p.a., ACS reagent, reag. Ph. Eur., ≥99.8% (GC)
Sigma-Aldrich
N,N-Dimethylformamide, suitable for HPLC, ≥99.9%
Sigma-Aldrich
Acetonitrile, electronic grade, 99.999% trace metals basis
Supelco
Acetonitrile, analytical standard
Sigma-Aldrich
Acetonitrile, anhydrous, 99.8%
Supelco
Trifluoroacetic acid, analytical standard
Sigma-Aldrich
Acetonitrile, biotech. grade, ≥99.93%
Sigma-Aldrich
Acetonitrile, suitable for HPLC, gradient grade, ≥99.9%
Sigma-Aldrich
Acetonitrile, for HPLC, for UV, ≥99.9% (GC)
Sigma-Aldrich
Acetonitrile, HPLC Plus, ≥99.9%
Sigma-Aldrich
Trifluoroacetic acid, ≥99%, for protein sequencing
Sigma-Aldrich
Acetonitrile, ACS reagent, ≥99.5%
Sigma-Aldrich
Acetonitrile, suitable for HPLC, gradient grade, ≥99.9%
Sigma-Aldrich
Trifluoroacetic acid, suitable for HPLC, ≥99.0%
Sigma-Aldrich
Trifluoroacetic acid, ReagentPlus®, 99%
Supelco
Acetonitrile, Pharmaceutical Secondary Standard; Certified Reference Material
USP
Residual Solvent Class 2 - Acetonitrile, United States Pharmacopeia (USP) Reference Standard
Sigma-Aldrich
Acetonitrile, ReagentPlus®, 99%
Sigma-Aldrich
Acetonitrile, for preparative HPLC, ≥99.8% (GC)
Sigma-Aldrich
Trifluoroacetic acid, puriss. p.a., suitable for HPLC, ≥99.0% (GC)
Sigma-Aldrich
Acetonitrile, suitable for DNA synthesis, ≥99.9% (GC)