This study was done to determine if the inflammation of the SG in TAO is induced by an infectious pathogen inside or if it is a reactive sterile inflammation.

The gene expression of HMGB1, TLR4, TLR9, and the RAGE were evaluated on the cDNA of the SG tissues of 24 TAO patients and two controls with hyperhidrosis by real-time PCR and analyzed by the Pfaffl method.

The gene expression of HMGB1 and TLR9 increased by about 25- and 2-fold changes in the SG of the TAO patients, respectively. There was no change in the gene expression of TLR4 or RAGE.

The study concluded through its findings that the inflammation in the SG of TAO patients is more likely a sterile inflammation, and its trigger may be mtDNA. Cadmium in cigarettes could be responsible for the induction of mtDNA release to the cell cytoplasm. The high expression of HMGB1 may play a role in the pathogenesis of TAO and may be responsible for both clinical manifestation of the disease and the imaging findings. Moreover, HMGB1 may be a target for treatment protocols for TAO.