Immunological studies on the cellular phenotype involved in corneal allograft rejection

Objective To investigate the cellular phenotype involved in corneal allogra ft rejection using whole mounts analysis. investigate the cellular phenotyp e meal allograft rejection using Methods Corneal transplantation was performed between Sprague Dawley (SD) a nd Wistar rats. Corneal wholemounts were prepared from control rats and tho se after corneal transplantation on day 7 and 12. Immunohistochemical stain was performed on these wholemounts using monoclonal antibodies to transfor ming growth factor beta 1 (TGF-beta 1), CD3, CD4, CD8, B lymphocytes, macro phages, dendritic cells and major histocompatibility complex (MHC) class II antigen. Results Corneal allograft rejection started on day 7 and reached its maximu m from 10 to 14 days after corneal transplantation. Presence of TGF-beta 1, CD3-, CD4-, CD8-, MHC class II-positive cells, macrophages and dendritic c ells were noted at the limbus of both SD rats and Wistar rats. No positive cell was present in the central cornea of normal rats. All positive cells b ut B lymphocyte were noted in large numbers in the cornea after corneal all ograft transplantation. Marked staining for TGF-beta 1 was noted during gra ft rejection. Conclusion The corneal wholemounts technique provides a good visualization for the cellular phenotype involved in corneal allograft rejection. A varie ty of cells including TGF-beta 1, CD3, CD4, CD8, MHC class II antigen posit ive cells, macrophages and dendritic cells are involved in corneal allograf t rejection. TGF-beta 1-positive cell might be an important immunosuppressi ve factor after corneal transplantation and also involved in the induction of fibrosis.