Radioimmunological detection of anti-transglutaminase autoantibodies in human saliva: a useful test to monitor coeliac disease follow-up.
BACKGROUND
Serum radioimmunoassay (RIA) tissue transglutaminase autoantibodies (tTG-Abs) proved to be a sensitive test also during coeliac disease (CD) follow-up. We demonstrated that RIA tTG-Abs could be detected in human saliva.


OBJECTIVE
To evaluate salivary RIA tTG-Abs in coeliac children on gluten-free diet (GFD).


METHODS
Saliva and serum samples from 109 coeliac children were evaluated at diagnosis (group 1: 71 females, median age 9.4 years) and 58 of them on GFD: 36 after 3-6 months (group 2a), 34 at 9 months or more (group 2b). Two gender- and age-matched control groups: 89 gastroenterological patients (group 3) and 49 healthy subjects (group 4) participated in the study. Saliva and serum tTG-Abs were detected by RIA and compared with serum tTG-Abs ELISA and IgA anti-endomysium antibodies (EMA).


RESULTS
Salivary RIA tTG-Abs were found in 94.5%, 66.7% and 50.0% of groups 1, 2a and 2b CD patients and in 98.2%, 72.2% and 50.0% of corresponding serum samples, respectively. tTG-Abs decreased with GFD progression and a correlation was found between saliva and serum titres (r = 0.75, P = 0.0001). During the CD follow-up, salivary and serum RIA sensitivities were comparable, and higher with respect to EMA and ELISA.


CONCLUSIONS
This study demonstrates that it is possible to detect salivary tTG-Abs with high sensitivity not only at CD diagnosis, but also during GFD.
Bonamico
M
M
Department of Paediatrics, Sapienza University of Rome, Rome, Italy. margherita.bonamico@uniroma1.it
Nenna
R
R
Luparia
R P L
RP
Perricone
C
C
Montuori
M
M
Lucantoni
F
F
Castronovo
A
A
Mura
S
S
Turchetti
A
A
Strappini
P
P
Tiberti
C
C
D001323:Autoantibodies / Q000032:analysis* / Q000097:blood; D002446:Celiac Disease / Q000175:diagnosis*; D002648:Child; D055050:Diet, Gluten-Free; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect / Q000379:methods; D005500:Follow-Up Studies; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis* / Q000097:blood; D008297:Male; D011863:Radioimmunoassay / Q000379:methods; D012463:Saliva / Q000737:chemistry*; D011503:Transglutaminases / Q000032:analysis*
D001323:Autoantibodies; D007070:Immunoglobulin A; D011503:Transglutaminases