CD40 and psoriasis: CD40 isa surface antigen related to T and B cell function, and CD44 has previously been shownto be upregulated in peripheral blood mononuclear cells (PBMCs) from psoriasis vulgarispatients compared to non-lesional areas (13).Moreover, CD80 and CD86 are significantly increased in PBMCs from psoriasis vulgarispatients than in healthy people, and their costimulatory abnormalities may play a rolein the pathogenesis of psoriasis (14,15).