EAE TCR MOTIFS AND ANTIGEN RECOGNITION IN MYELIN BASIC PROTEIN-INDUCED ANTERIOR UVEITIS IN LEWIS RATS

T cells infiltrating the iris/ciliary body of Lewis rats with anterior uveitis (AU) that had been induced by myelin basic protein (MBP) immu nization were previously found to share surface markers common to the T cells that cause experimental autoimmune encephalomyelitis (EAE). To determine whether these AU-associated T cells are in fact the same as those that infiltrate the central nervous system to cause EAE, we exa mined TCR V gene expression in T cells infiltrating the anterior chamb er in rats with AU, As with EAE, we found a biased expression of V bet a 8.2 and V alpha 2 in the iris/ciliary body and, although one would e xpect an influx of nonspecific inflammatory T cells, these biases were still evident at the peak of AU. An analysis of the TCR V beta 8.2 an d V alpha 2 sequences derived from the iris/ciliary body demonstrated the presence of the same complementarity determining region 3 motifs f ound in MBP-specific T cells that are pathogenic for EAE and found in T cells derived from the central nervous system of rats with EAE. Fina lly, T cells isolated from the iris/ciliary body of rats with AU were found to proliferate in a specific fashion to MBP Ags. Thus, it appear s that MBP-specific T cells are pathogenic for AU as well as EAE in th e Lewis rat. In addition, the long-term presence of this highly restri cted MBP response in the iris/ciliary body indicates that distinct imm unoregulatory mechanisms exist in the environment of the eye. This pro vides an interesting model with which to address questions pertaining to the nature of T cells infiltrating the eye and their regulation dur ing EAE and other systemic diseases.