Antibodies to wheat high-molecular-weight glutenin subunits in patients with celiac disease.
BACKGROUND
Wheat gluten comprises gliadins and glutenins. The high-molecular-weight (HMW) glutenin subunits (GS)-1Dy10 are toxic for patients with celiac disease (CD). This study aimed to assess whether CD patients mount a serological response to HMW-GS-1Dy10.


METHODS
Recombinant HMW-GS-1Dy10 was deamidated using human recombinant tissue transglutaminase. MALDI-TOF was performed to compare the level of deamidation of glutamine residues between material before and after treatment. Enzyme-linked immunosorbent assays were developed. Sera from patients with untreated CD and gastrointestinal disease controls were tested and receiver operator characteristics were used to calculate cutoffs.


RESULTS
MALDI-TOF revealed a number of fragments matching known HMW-GS-1Dy10 sequences within both the deamidated and non-deamidated material. Evidence of deamidation of glutamine residues was found only within the human transglutaminase-treated material. Patients with untreated CD had significantly increased levels of serum antibodies to HMW-GS-1Dy10 compared to controls. Undeamidated HMW-GS-1Dy10 IgA antibodies had sensitivities and specificities of 72.5 and 78.26%, respectively. Deamidated HMW-GS-1Dy10 IgA antibodies had sensitivities and specificities of 76.8 and 65.2%. Undeamidated HMW-GS-1Dy10 IgG antibodies had sensitivities and specificities of 75.3 and 68.1%. Deamidated HMW-GS-1Dy10 IgG antibodies had sensitivities and specificities of 36.2 and 92.8%.


CONCLUSIONS
Patients with untreated CD have raised antibody levels to HMW-GS-1Dy10, indicating the participation of these proteins in the adaptive immune response to gluten. Discrimination between CD patients and controls is not enhanced by deamidation of HMW-GS-1Dy10. Thus antibodies to these proteins are not useful markers for CD detection.
Division of Diabetes and Nutritional Sciences, King's College London, London, UK. julia.ellis@kcl.ac.uk
H Julia
HJ
Ellis
Pablo
P
Lozano-Sanchez
Carmen
C
Bermudo Redondo
Tanja
T
Šuligoj
Federico
F
Biagi
Paola I
PI
Bianchi
Gino R
GR
Corazza
Annalisa
A
De Silvestri
Enzo
E
Bravi
Ioanis
I
Katakis
Ciara K
CK
O'Sullivan
Paul J
PJ
Ciclitira
D056704:Adaptive Immunity; D000595:Amino Acid Sequence; D000906:Antibodies / Q000097:blood / Q000276:immunology; D000918:Antibody Specificity; D002446:Celiac Disease / Q000097:blood / Q000175:diagnosis* / Q000276:immunology*; D005903:Gliadin / Q000737:chemistry / Q000276:immunology*; D005983:Glutens / Q000737:chemistry / Q000276:immunology*; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood / Q000276:immunology; D008969:Molecular Sequence Data; D008970:Molecular Weight; D021122:Protein Subunits / Q000737:chemistry / Q000276:immunology; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D011503:Transglutaminases / Q000378:metabolism; D014908:Triticum / Q000737:chemistry / Q000276:immunology*
D000906:Antibodies; D007070:Immunoglobulin A; D021122:Protein Subunits; D011994:Recombinant Proteins; D005983:Glutens; D005903:Gliadin; D011503:Transglutaminases; C037302:glutenin