Abstract
Purpose: :
In this study we evaluated the presence of T-helper17 lymphocytes (Th17) in the healthy ocular surface and in patients with ocular cicatricial pemphigoid (OCP).
Methods: :
Conjunctival biopsies and blood samples were obtained from 9 patients with OCP (4 males, 5 females; 53-91 years of age) and 5 age/sex matched-healthy subjects. Conjunctival samples were immunostained with anti-human IL17 antibodies (Immunodiagnostick AG) and IL17+ cells were counted by confocal microscopy in three 60x field images per each sample. Mononuclear cells were isolated from both OCP and healthy blood samples and evaluated for foxp3-FITC, IL17-Cy3, or CD4-Cy5 (eBioscience) by FACS. IL17, TGF-β, IL4 and IFN-γ (eBioscience) levels were investigated in plasma of OCP and healthy patients by ELISA.
Results: :
Presence of Th17 lymphocytes in conjunctival biopsies was significantly (p<0.01) increased in patient with OCP (15±13cellsxfield) as compared to healthy subjects (0.5±1.5cellsxfield). No significant difference was observed for IL17 between the OCP and healthy subjects in peripheral blood.
Conclusions: :
In this study we report an increased recruitment of Th17 lymphocytes in OCP conjunctiva, not accompanied by similar peripheral findings. This data suggests that Th17 lymphocytes are responsible of a dysregulation in the local immune response of OCP conjunctiva. Our findings are in line with previous evidence showing that Th17 cells play a critical pathogenic role in autoimmunity, promoting organ-specific damage in several diseases such as rheumatoid arthritis and psoriasis.
Keywords: conjunctiva • immunomodulation/immunoregulation • autoimmune disease