The T-Cell-Receptor Repertoire in the Synovial Fluid of a Patient with Rheumatoid Arthritis is Polyclonal

We have analyzed the T-cell-receptor repertoire expressed in the synovial fluid of a patient with rheumatoid arthritis by using an inverse polymerase chain reaction. Total RNA was isolated from Ficoll-purified mononuclear cells and converted into circularized double-stranded cDNA. Specific amplification of α- and β-chain variable regions (Vα and Vβ) was achieved with inverted α- and β-chain constant region (Cα and Cβ) primer pairs, and the amplification products were cloned into phage vectors. A total of 78 α and 76 β clones were sequenced, and 67 and 72 productively rearranged α and β genes were identified, respectively. Thirty-one Vα, 33 α-chain joining region (Jα), 29 Vβ, and 12 β-chain joining region (Jβ) gene segments were found in the productively rearranged clones, indicating that the T-cell repertoire expressed in the synovial fluid of this RA patient is highly heterogenous and polyclonal. Comparison of peripheral blood and synovial fluid repertoires showed that the most abundant Vβ sequences, Vβ2.1 and Vβ3.1, were enriched in the inflamed joint by a factor of 2 to 3. It is possible that T cells expressing these Vβ gene segments, which recognize bacterial superantigens, play a role in the disease.