Corneal endothelial cells create and maintain a unique microenvironment for immune cells

Corneal endothelial (CE) cells may play a role in the creation and maintenance of the unique immunologic microenvironment in the anterior chamber. A monolayer of LEW rat CE cells did not present antigen to MHC compatible T-cell lines, but rather inhibited the proliferative response. The inhibition was not MHC-restricted nor species-specific. The split-well assay directly indicated the existence of an immunosuppressive factor(s) in the cell-free culture supernatant. IL-2R on T cells activated on APC in the presence of CE cells was upregulated, as evidenced by the response to the addition of exogenous IL-2. CE cells, as well as culture supernatant, also supported the viability of T cells.