Table 1.

Tools employed to detect intestinal production of anti-TG2 autoantibodies.

Tool	Technique	Strengths	Weaknesses	References
Detection of anti-reticulin antibodies in jejunal juice	Indirect immunofluorescence on frozen sections of kidney rat		– Low sensitivity – Difficulty in getting the samples – Requires frozen samples of kidney rat and highly experienced operators – Unreliable as diagnostic test	(80)
Detection of EMA in fecal supernatants	Indirect immunofluorescence on frozen sections of monkey esophagus	– High sensitivity – Easy to get fecal samples	– Requires frozen monkey esophagus samples and highly experienced operators – Culture system technology requires experienced operators	(81)
Measurement of EMA in supernatants from cultured biopsy experiments	Indirect immunofluorescence on frozen sections of monkey esophagus	High sensitivity	– Requires frozen monkey esophagus samples and highly experienced operators – Culture system technology requires experienced operators	(56, 82, 88, 89)
Measurement of anti-TG2 IgA antibodies in fecal supernatants	ELISA	– Easy to get fecal samples	Sensitivity lower than serum tests	(81)
Measurement of anti-TG2 IgA antibodies in supernatants from cultured biopsy experiments	ELISA	– High sensitivity and specificity – ELISA Test is not dependent on operator skill – Quantitative test	Culture system technology requires experienced operators and equipped laboratories	(83–85, 88, 90, 91)
Detection of mucosal IgA anti-TG2 deposits	Double immunofluorescence on frozen duodenal sections	– High sensitivity – High specificity	– Requires frozen duodenal sections, highly experienced operators and equipped laboratories – Semiquantitative test	(84–87, 89, 91–93, 98)
Detection of synthesized IgA anti-TG2 from intestinal B lymphocytes	Phage display libraries	– High sensitivity – High specificity	– Tested in small patient groups and by only one group of researchers – Highly complex test that requires experienced operators and equipped laboratories – It cannot be proposed for routine use	(57, 94)
Detection of anti-TG2-specific plasma cells	Double immunofluorescence on frozen duodenal sections	– High sensitivity – High specificity	Requires frozen duodenal sections, highly experienced operators and equipped laboratories	(58, 59, 61)
Sorting TG2-specific plasma cells	Flow cytometry		Requires freshly picked duodenal samples, highly experienced operators and equipped laboratories	(58, 61, 64, 65)

Anti-TG2, anti-tissue transglutaminase2 antibodies; EMA, anti-endomysium antibodies.