Molecular Analysis of T-Cell Receptor β Genes in Cutaneous T-Cell Lymphoma Reveals Jβ1 Bias

Molecular characterization of T-cell receptor junctional region sequences in cutaneous T-cell lymphoma had not been previously reported. We have examined in detail the features of the T-cell receptor beta (TCRB) gene rearrangements in 20 individuals with well-defined stages of cutaneous T-cell lymphoma (CTCL) comprising 10 cases with early-stage mycosis fungoides (MF) and 10 cases with late-stage MF or Sezary syndrome. Using BIOMED-2 PCR primers, we detected a high frequency of clonally rearranged TCR gamma and TCRB genes (17/20 and 15/20 cases, respectively). We carried out sequencing analysis of each complete clonal variable (V)β-diversity (D)β-joining(J)β fingerprint generated by PCR amplification, and determined the primary structure of the Vβ-Dβ-Jβ junctional regions. We observed considerable diversity in the T-cell receptor Vβ gene usage and complementarity-determining region 3 loops. Although we found that TCRB gene usage in CTCL and normal individuals share common features, our analysis also revealed preferential usage of Jβ1 genes in all cases with advanced stages of disease.