HLA allele associations and V-beta T-lymphocyte expansions in patients with psoriasis, harboring toxin-producing Staphylococcus aureus.

HLA alleles have been associated with psoriasis. Toxin-producing strains of Staphylococcus aureus behave as superantigens, and if present in patients, might play a role in the exacerbation of psoriatic lesions by activating certain V-beta (V beta) T-lymphocyte subsets. Allele frequencies in 22 patients and 22 controls (alleles determined by DNA/SSP typing) were used to calculate a relative risk of $4.