RESTRICTED T-CELL RECEPTOR V-BETA GENE USAGE IN THE SKIN OF PATIENTS WITH GUTTATE AND CHRONIC PLAQUE PSORIASIS

A strong association between acute guttate psoriasis and group A, beta -haemolytic streptococcal infections is well established. Furthermore, streptococcal M proteins and toxins have been shown to act as superan tigens, stimulating subpopulations of T lymphocytes expressing particu lar Vbeta families. We have therefore studied the possible role of str eptococcal superantigens in psoriasis by staining peripheral T lymphoc ytes and skin sections from patients with guttate or chronic plaque ps oriasis for the expression of nine TCR Vbeta families, using a range o f monoclonal antibodies. A marked over-representation of Vbeta2+ T lym phocytes was observed in the dermis and epidermis of patients in both groups, when compared with T lymphocytes in their peripheral blood. A less marked dermal increase in Vbeta5.1+ T lymphocytes was also observ ed in these patients. These findings are consistent with the involveme nt of a superantigen, possibly streptococcal, in the pathogenesis of p soriasis.