T-Cell-Receptor Repertoire in Chronic Plaque-Stage Psoriasis Is Restricted and Lacks Enrichment of Superantigen-Associated Vβ Regions

Preferential usage of certain T-cell receptors by the lymphocytic infiltrate in psoriasis might indicate the involvement of an antigen in the pathogenesis of this disease. However, to date there are no data on the complete T-cell-receptor Vα and Vβ repertoire in psoriatic patients. We therefore compared the usage of T-cell-receptor variable regions in blood and skin of 10 patients with chronic plaque-stage psoriasis by means of semiquantitative polymerase chain reaction. Additionally, HLA class II alleles were analyzed by means of sequence-specific oligonucleotide typing. A considerable restriction of the T.-cell-receptor repertoire was observed in the skin, where up to 20% of the variable regions present in the blood were not detectable. This was true for both α- and β-chains. However, no interindividually constant pattern of T-cell-receptor restriction was deducible, Inconsistently, a certain preferential usage of some β chains occurred within the cutaneous compartment. This report on the complete T-cell–receptor Vα and Vβ repertoire in psoriasis documents the restricted receptor repertoire of infiltrating T cells and a lack of enrichment of superantigen-associated Vβ regions, Thus superantigens seem not to play a pathogenetically relevant role in chronic plaque-stage psoriasis.