Expression of Vβ gene segments by Sezary cells

Abstract

The T-cell receptor Vβ repertoire expressed by Sezary cells was determined in a series of 16 patients whose samples have been shown to contain a majority of tumor cells, By using anti-Vβ monoclonal-antibodies, polymerase chain reaction analysis of expressed Vβ, and, in selected cases, nucleotide sequencing, we have shown that the expressed Vβ segments belong to five Vβ families (Vβ5, Vβ6, Vβ8, Vβ13, and Vβ18), which contain a large fraction of the T-cell receptor Vβ, repertoire and do not share significant similarities in complementary determining region 4. Vβ segments from these five families were also found to be strongly expressed by CD4+CD7- peripheral blood cells obtained by fluorescence-activated cell sorting from two healthy donors. The diversity of the Vβ repertoire expressed by Sezary cells appears of be similar to that expressed by circulating non-neoplastic T cells. These data do not support the hypothesis that a common superantigen is involved in the initiation of this form of cutaneous T-cell lymphoma.