Regulatory T Cells Specific for the Same Framework 3 Region of the Vβ8.2 Chain Are Involved in the Control of Collagen II–induced Arthritis and Experimental Autoimmune Encephalomyelitis

Recent evidence indicates that chronic autoimmune disease can result from breakdown of regulation and subsequent activation of self-reactive T cells. In many murine autoimmune disease systems and in the Lewis rat, antigen-specific T cells utilizing the T cell receptor (TCR) Vβ8.2 gene segment play a major role. In the myelin basic protein–induced experimental autoimmune encephalomyelitis (EAE) model in H-2u mice, we had shown that T cells recognizing a peptide determinant within the framework 3 region of the Vβ8.2 chain have a critical role in influencing the course of the disease. Here, we report experiments in another disease system, collagen II (CII)–induced arthritis (CIA) in DBA/1LacJ (H-2q) mice, indicating a remarkably parallel control circuit to that found for EAE. A critical role is played by CII-specific Vβ8.2bearing T cells in the CIA system, which we have confirmed. Animals treated with the superantigen SEB before CII administration are significantly protected from CIA. Next, we tested the ability of peptides encompassing the entire Vβ8.2 chain to induce proliferative responses. Only TCR peptide B5 (amino acids 76–101), a regulatory peptide in EAE, induced proliferation