Higher Sensitivity and Earlier Identification of Celiac Disease Autoimmunity by a Nonradioactive Assay for Transglutaminase Autoantibodies

Figure 1

Titration of TGA by both RIA and ECL assay using a TGA positive sample from six of T1D patients studied with confirmed clinical CD by biopsy (marked patient 1, patient 2, patient 3, patient 4, patient 5, and patient 6, respectively). The samples were in a serial of 1 : 1 dilution with a normal control serum to a maximum of 1 : 4096 dilutions. The solid curves were TGA levels from ECL assay and the dotted curves with gray color were TGA levels from RIA. A horizontal dotted line represents assay cut-offs for both ECL and RIA at 3 standard deviation (SD) scores. The SD scores are calculated with the following formula: (index value − mean index of controls)/SD.