Abstract
Purpose: :
We have previously developed a model of anterior scleritis by modifying the collagen-induced autoimmune arthritis model. To ascertain the pathogenesis of scleritis, we further modified this model and conducted immunological analyses.
Methods: :
To an 8-week-old DBA/1J mouse, bovine type II collagen (CII) emulsified using complete Freund's adjuvant (CFA) was injected subcutaneously back of the neck for primary immunization, then 21 days later, CII emulsified using CFA was injected subcutaneously around the eye for challenge immunization to induce both arthritis and anterior scleritis. In another mouse, CII was injected for primary immunization, and CFA alone was injected for challenge immunization. In yet another mouse, CII was not injected at all, and only CFA was injected around the eye. In all models, arthritis and ocular infiltrating cells were analyzed.
Results: :
In the model immunized twice with CII, arthritis was severe and scleral vessels were dilated. On histological examination, anterior scleral thickening and CD4+ and CD11b+ cell infiltration were seen. In models immunized with CII only once or not at all that received CFA, arthritis did not occur, and local ocular findings were not marked. While CD4+ cells were not seen in the eyes of these models, CD11b+ cell infiltration was more marked when compared to normal eyes.
Conclusions: :
When immunized twice with CII, an acquired immunological response caused arthritis and anterior scleritis. Even when CII immunization was incomplete and only CFA was injected around the eye, macrophage-dominant antigen nonspecific anterior scleritis occurred.
Keywords: autoimmune disease • sclera • inflammation