title: A non-toxic analogue of a coeliac-activating gliadin peptide: a basis for immunomodulation?
abstract: BACKGROUND
  A-gliadin residues 31-49 (peptide A) binds to HLA-DQ2 and is toxic to coeliac small bowel. Analogues of this peptide, which bind to DQ2 molecules but are non-toxic, may be a potential route to inducing tolerance to gliadin in patients with coeliac disease.
  
  
  METHODS
  Toxicity was investigated with small bowel organ culture in six patients with untreated coeliac disease, four with treated coeliac disease and six controls. Analogue peptides comprised alanine substituted variants of peptide A at L31 (peptide D), P36 (E), P38 (F), P39 (G) and P42 (H).
  
  
  RESULTS
  Peptides D and E were toxic in biopsies from some patients. Peptides F, G and H were not toxic.
  
  
  CONCLUSIONS
  Peptide F, which binds to DQ2 more strongly than peptide A, is not toxic in patients with coeliac disease in-vitro; this could be an initial step towards investigation of the induction of tolerance to gliadin in patients affected by coeliac disease.
authors.affiliation: Gastroenterology Unit, GKT, St. Thomas' Hospital, London, UK.
authors.forename: F
authors.initials: F
authors.lastname: Biagi
authors.forename: H J
authors.initials: HJ
authors.lastname: Ellis
authors.forename: N D
authors.initials: ND
authors.lastname: Parnell
authors.forename: R G
authors.initials: RG
authors.lastname: Shidrawi
authors.forename: P D
authors.initials: PD
authors.lastname: Thomas
authors.forename: N
authors.initials: N
authors.lastname: O'Reilly
authors.forename: G R
authors.initials: GR
authors.lastname: Corazza
authors.forename: P J
authors.initials: PJ
authors.lastname: Ciclitira
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000595:Amino Acid Sequence; D016022:Case-Control Studies; D002446:Celiac Disease / Q000276:immunology* / Q000378:metabolism; D005260:Female; D005903:Gliadin / Q000276:immunology*; D006683:HLA-DQ Antigens / Q000378:metabolism*; D006801:Humans; D007583:Jejunum / Q000276:immunology; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009924:Organ Culture Techniques; D010446:Peptide Fragments / Q000276:immunology*; D011485:Protein Binding
chemical_list: D006683:HLA-DQ Antigens; D010446:Peptide Fragments; D005903:Gliadin