Aims Thyroid orbitopathy (TO) is an autoimmune
inflammatory disorder characterised by several ocular
manifestations. Several autoantigens have been proposed
to be involved in the pathogenesis of TO, but the
autoantigen system and the mechanism of TO would be
rather complex. In this study, an immunoproteomic
method was used to survey novel autoantigens
expressed in the orbital fat tissue of patients with TO.
Methods We used immunoproteomic, ELISA and
immunohistochemical staining methods to survey novel
autoantigens expressed in the orbital fat tissue of
patients with TO.
Results Six protein spots showing high reactivity with
the serum from the patients with TO were detected as
candidate orbital autoantigens, and two of them
(carbonic anhydrase 1 (CA1) and alcohol dehydrogenase
1B (ADH1B)) were further verified by ELISA and
immunohistochemical staining. We found that CA1 and
ADH1B could attribute target autoantigens in this
autoimmune disease. We discovered anti-CA1 and anti-
ADH1B antibody prevalence to be higher in patients
with TO (68.57%/51.43%) or Graves’ disease (GD)
(72%/48%) than in healthy controls respectively.
Immunohistochemical staining study revealed the
significantly enhanced expressions of CA1 and ADH1B in
orbital fat of TO compared with that in healthy controls.
Conclusions We found that CA1 and ADH1B could
attribute target autoantigens in this autoimmune
disease. The high prevalence of these autoantibodies
against CA1 and ADH1B in patients with TO and GD
clarifies the potential clinical role for anti-CA1 and anti-
ADH1B antibodies as biomarkers for GD and TO.
