From the Guidelines
Celiac antibodies are immune system proteins that the body produces in response to gluten ingestion in individuals with celiac disease.
Types of Celiac Antibodies
- Anti-type 2 transglutaminase antibodies (TG2Ab): These are the primary antibodies used for screening and diagnosis of celiac disease, with high sensitivity (93%) and specificity (98%) 1.
- Anti-endomysial antibodies (EMAs): These are used as a second-line test, with high specificity, but lower sensitivity compared to TG2Ab 1.
- IgA and IgG antibodies: These are used to detect the presence of celiac disease, with IgA being the primary antibody and IgG being used in cases of IgA deficiency 1.
Role in Diagnosis
Celiac antibodies play a crucial role in the diagnosis of celiac disease, with serological tests being the first-line screening method 1.
- A positive test result indicates the presence of celiac disease, but a negative result does not rule out the disease entirely 1.
- Intestinal biopsy is still required to confirm the diagnosis, especially in cases with uncertain or negative serological test results 1.
Clinical Significance
The presence of celiac antibodies is a key indicator of celiac disease, and their detection is essential for timely diagnosis and treatment 1.
- Early diagnosis and treatment can prevent long-term complications, such as malabsorption, osteoporosis, and increased risk of certain cancers 1.
From the Research
Definition of Celiac Antibodies
- Celiac antibodies refer to the autoantibodies present in individuals with celiac disease, a multisystemic dietary, gluten-induced autoimmune disorder 2.
- These antibodies target members of the transglutaminase (TG) family, including TG2, TG3, and TG6, and are deposited in small-bowel mucosa and extraintestinal tissues affected by the disease 2.
Types of Celiac Antibodies
- IgA and IgG transglutaminase antibodies (TGA) are commonly used as diagnostic aids for celiac disease 3.
- Endomysial antibodies (EMA) and antibodies against tissue transglutaminase (tTG) are also used in the diagnosis of celiac disease 3, 4.
- Deamidated gliadin peptides are recognized by celiac disease-specific antibodies, which have improved the usefulness of gliadin antibodies in diagnosis 4.
Role of Celiac Antibodies in Diagnosis
- Serum antibodies to transglutaminase 2 (TG2) are increasingly used to diagnose celiac disease, particularly in children 5.
- The presence of IgA anti-TG2 antibodies in serum is considered a hallmark of celiac disease and is relevant from a clinical viewpoint 6.
- Intestinal anti-TG2 autoantibodies may have pathogenic and clinical implications for celiac disease, although their role in the development of the celiac lesion remains to be defined 6.
Characteristics of Celiac Antibodies
- Celiac antibodies are produced at the intestinal level and are deposited in the small-bowel mucosa before appearing in circulation 6.
- The production of anti-TG2 autoantibodies is thought to be triggered by gliadin-specific T cells, and limited somatic mutations have been observed in VH and VL genes in TG2-specific plasma cells 6.