title: Factor XIII and tissue transglutaminase antibodies in coeliac and inflammatory bowel disease.
abstract: Tissue transglutaminase (tTg) has been identified as an autoantigen in coeliac disease (CD). There is a marked homology between different forms of transglutaminase, such as tTg and coagulation factor XIII. We compared titres of both IgA- and IgG-antibodies against these two antigens in 20 CD patients, 20 endomysial antibody (EMA)-negative controls and a group with inflammatory bowel disease (34 with Crohn's disease and 23 with ulcerative colitis). IgA-antibodies against tTg correlated with EMA titres and had high sensitivity and specificity in screening for CD. Only in two CD patients were high titres found of IgA-antibodies against factor XIII, non-reactive with tTg. Both lacked bleeding tendency. The presence of IgG-antibodies against tTg, in contrast, had low sensitivity and specificity in screening for CD and were frequently seen in inflammatory bowel disease. Similarly, factor XIII IgG-antibodies displayed a non-specific pattern with modestly elevated titres in patients with Crohn's disease and in both EMA-negative and positive patients. Despite a marked homology with tTg, the occurrence of high titre IgA-antibodies against factor XIII is infrequent in CD, but may-when present-be the result of epitope spreading. The presence of IgG-antibodies in CD and inflammatory bowel disease illustrates the complexity of autoantibody reactions in gastrointestinal disease.
authors.affiliation: Department of Medicine, Lund University, University Hospital, SE-205 02 Malmö, Sweden. klas.sjoberg@medforsk.mas.lu.se
authors.forename: Klas
authors.initials: K
authors.lastname: Sjöber
authors.forename: Sten
authors.initials: S
authors.lastname: Eriksson
authors.forename: Birgitta
authors.initials: B
authors.lastname: Tenngart
authors.forename: E Bodil
authors.initials: EB
authors.lastname: Roth
authors.forename: Hakon
authors.initials: H
authors.lastname: Leffler
authors.forename: Pål
authors.initials: P
authors.lastname: Stenberg
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000918:Antibody Specificity; D001323:Autoantibodies / Q000097:blood*; D016022:Case-Control Studies; D002446:Celiac Disease / Q000276:immunology*; D003093:Colitis, Ulcerative / Q000276:immunology*; D003424:Crohn Disease / Q000276:immunology*; D003429:Cross Reactions; D005176:Factor XIII / Q000276:immunology*; D005260:Female; D019204:GTP-Binding Proteins / Q000276:immunology*; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D008875:Middle Aged; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D011503:Transglutaminases / Q000276:immunology*
chemical_list: D001323:Autoantibodies; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D005176:Factor XIII; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D011503:Transglutaminases; D019204:GTP-Binding Proteins