Introduction: We recently reported a high prevalence of |TgAb in sera from healthy Sri Lankan subjects. To characterise these further we have studied the reactions of these Abs with Tg in a competitive ELISA with a panel of 10 Tg monoclonal Abs (TgMabs). This is compared to a similar UK population of healthy subjects and AITD patients.
Methods: The sera, all from females, comprised: 1. Healthy SL schoolgirls with high TgAb (HSL; n=33) 2. Healthy SL Tamil Tea Estate Workers with high TgAb (TSL; n=48), 3. Healthy UK subjects with high TgAb (HUK; n=12) 4. AITD patients from UK (AITDUK; n=14) and 5. AITD SL (AITDSL; n=10). Six antigenic clusters (I-VI) were defined by the TgMabs. A percentage inhibition of >70% was taken as complete inhibition and 35-70% as partial inhibition.
Results: AITD sera from both UK and SL patients exhibited the typical epitope restriction pattern, recognising clusters I and IV while HSL and HUK sera did not preferentially recognise any clusters. On the other hand, TSL recognised the autoimmune epitopes I and IV, and in addition, recognised cluster VI significantly more than any other group (P<0.005).
Conclusion: Tamil tea workers recognise an additional epitopic cluster the significance of which remains to be determined.
08 - 11 Apr 2002
British Endocrine Societies