Background: Sézary syndrome (SS) is a cutaneous T-cell lymphoma characterized by erythroderma, lymphadenopathy and malignant clonal T cells in the skin, lymph nodes and peripheral blood. A role for superantigens in the pathogenesis of SS has been postulated before.
Objectives: To investigate a putative involvement of chronic (super-)antigenic stimulation in driving T-cell expansion in SS.
Methods: Antigenic specificity of the T-cell receptor (TCR) was assayed by molecular analysis of the TCRA (n=11) and TCRB (n=28) genes, followed by detailed in silico analysis.
Results: Sequence analysis of clonally rearranged TCRB genes showed over-representation of Vβ8, Vβ13, Vβ17, Vβ21 and Vβ22, and under-representation of Vβ2 and Jβ1.1 when compared with healthy controls. No similarity was detected in amino acid motifs of the complementarity determining region 3 (CDR3). Analysis of TCRA rearrangements showed that there was no common Vα or Jα gene usage, and that TCRA CDR3 amino acid motifs were not highly similar.
Conclusions: The lack of clear stereotypic TCRA and TCRB CDR3 amino acid motifs would argue against involvement of a single common antigen in the pathogenesis of SS. Nevertheless, the skewing of Vβ and Jβ gene usage does seem to point to a restricted TCR repertoire, possibly as a result of superantigenic selection prior to neoplastic transformation.
© 2011 The Authors. BJD © 2011 British Association of Dermatologists 2011.