Abstract
Purpose: :
Expression and release of cytokines, surface display of cytokine receptors have been reported in the orbital connective tissue of patients with Graves’ orbitopathy (GO). Changes in tear film proteins, osmolarity and ocular surface functions have also been described in GO. Our aim was to determine the levels of proinflammatory cytokines (IL 1 beta, IL 6, TNF alpha) in tears of patients with GO.
Methods: :
Tear samples were collected from 50 GO patients (10 male, 40 female, age: 52.06 ± 10.36 yrs) and 11 healthy controls (5 male, 6 female, age: 53.45 ± 23.64 yrs). Levels of cytokines were measured by ultrasensitive ELISA. Patients also underwent careful ophthalmological examination including Clinical Activity Score (CAS) in each case.
Results: :
In the tears of GO patients IL 1 beta and IL 6 were significantly increased: the mean levels of IL 1 beta and IL 6 were 231.8 ± 75 pg/ml and 218.1 ± 40 pg/ml respectively. In control subjects, IL 1 beta and IL 6 were 39.6 ± 11.9 pg/ml (p <0.05) and 7.7 ± 2.3 pg/ml, respectively (p<0.01 ). TNF alpha levels were also found to be higher in GO (29.3 ± 11.4 pg/ml vs. <0.5 pg/ml in controls). Although the concentration of cytokines varied between subjects, increased levels of at least two cytokines were noticeable at patients with active GO (CAS>4).
Conclusions: :
Impaired cytokine balance can be observed in tears of GO patients, especially of those with immunologically active disease. Proinflammatory cytokine secretion in tears can be a useful indicator of autoimmune activity.
Keywords: autoimmune disease • cytokines/chemokines • orbit