Clonal accumulation of T cells bearing V beta 6 T-cell receptor in chronic inflammatory periodontal disease.

Abstract

Our previous study demonstrated that among the various T-cell receptor V beta gene segments, T-cell receptor V beta 6 gene-bearing T cells are predominant in periodontitis lesions. To explore the clonality of T cells expressing V beta 6 T-cell receptor, which is determined by the heterogeneity of the complementarity-determining region 3(CDR3), V beta 6-C beta polymerase chain reaction products derived from gingival tissue and peripheral blood of periodontitis patients were analyzed by single-strand conformation polymorphism and nucleotide sequence. Both techniques provided quite similar results in terms of the number of accumulated clones in which clonal accumulation of T-cell receptor V beta 6-bearing T cells was found in most periodontitis lesions but not in peripheral blood. From the analysis of deduced amino acid sequences, a possible conserved amino acid residue in the CDR3 region of the periodontitis lesion-derived sequences was found in most patients. This conserved amino acid motif however, was not identified. Furthermore, skewed J beta gene segment usage was observed for expanded clones from periodontitis lesions. Our results suggest that T cells infiltrating periodontitis lesions are responding to a restricted number of antigens or epitopes.