[Differential expression of HLA DR, DP and DQ in cultivated, human ciliary body epithelial cells].

The antigen-specific activation of T-helper lymphocytes is dependent on the presentation of antigen in context with the gene products of major histocompatibility complex class II (MHC II). Aberrant expression of MHC II on the ciliary epithelium has been observed in uveitic eyes, which may enable these cells to interact specifically with lymphocytes and may play a role in ocular autoimmunity. Human MHC II consists of three subclasses, termed HLA DR, DP and DQ, which seem to be differentially regulated and may have different functions. The present study was initiated to investigate the dynamics of the differential MHC II expression on cultured human non-pigmented ciliary epithelial cells (NPE cells) in response to gamma-interferon by means of immunohistochemistry. NPE were isolated by a technique of selective adhesion to tissue culture substrate, and growth was induced after transfection with an origin-defective mutant of SV-40 virus DNA. NPE grown in control tissue culture medium did not express MHC class II. HLA DR and DP could be induced by incubation with low concentrations of gamma-IFN for short periods. HLA DQ was expressed only weakly even with higher doses of gamma-IFN and longer incubation periods. The differential expression of HLA DR and DP, compared to HLA DQ in response to gamma-IFN in the ciliary epithelium, is similar to observations in other non-lymphoid ocular cells, but appears to be different from the regulation of MHC II on lymphoid cells.(ABSTRACT TRUNCATED AT 250 WORDS)