Immunological mechanisms involved in psoriasis

Abstract

The past decade has borne witness to tremendous advances in our knowledge of the pathogenesis of psoriasis and the weight of evidence is now on the side of the T cell as being an integral mediator of this process. Advances in molecular technology have enabled direct in vivo measurement of cytokines and, although no animal model exists for the study of psoriasis, the use of cyclosporine has served as an excellent investigatory tool. The utilization of therapeutics to study psoriatic mechanisms is an unusual approach in that one must derive conclusions from disappearance of measurable factors such as cytokines and assume that these same factors are vital to the initiation and maintenance of a psoriatic plaque. Studying disease evolution using the Koebner phenomenon or relapse following treatment would supply a more accurate picture of initiating events. Based on the immune hypothesis, therapeutic modalities which are now entering the arena include T cell vaccination, particularly if psoriasis-specific T cell receptor V β -restricted clones can be isolated from psoriatic plaques.