The role of complement activation in the pathogenesis of Fuchs’ dystrophy

• The level of the complement activation products was elevated in the aqueous humor of Fuchs’ dystrophic patients.
• The complement system was activated both through the classical and alternative pathways in the aqueous humor.
• No correlation was found between the duration of the corneal oedema and the level of the complement activation products.
• No difference was found as regards the level of the complement activation products between the patients with stage 2 or stage 3 disease.

PurposeInflammation can be an etiologic factor of Fuchs’ dystrophy according to previous studies. Our aim was to analyse the activation of the complement system in the aqueous humor in this pathological condition.Methods100 μl aqueous humor sample was taken during keratoplasty of 11 Fuchs’ dystrophic patients and during phacoemulsification surgery of 18 control patients. The samples were mixed with EDTA and stored at −80 °C. Concentrations of C1rC1sC1Inh and C3bBbP complexes as markers of the activation of the classical and alternative complement pathways, respectively, were measured with ELISA method. The results of the patient group and the control group were compared with statistical analysis (non-parametric Mann Whitney test).ResultsBoth the concentrations of C1rC1sC1Inh [4.3 (3.2–20.2) AU/ml] and of C3bBbP [15.3 (7.8–22.6) AU/ml] were significantly higher in the Fuchs’ dystrophic group than in the control group [C1rC1sC1Inh: 0.0 (0.0–5.6) AU/ml, C3bBbP: 1.4 (0.0–7.8) AU/ml]. The median value is shown along with the (25% and 75% percentiles).ConclusionsBased on our results, the complement system may be activated both through the classical and alternative pathways in the aqueous humor of the patients with Fuchs’ dystrophy.