ANTI-CHEMOTACTIC ACTIVITIES OF PEPTIDE-T - A POSSIBLE MECHANISM OF ACTIONS FOR ITS THERAPEUTIC EFFECTS ON PSORIASIS

Peptide T is an octapeptide (ASTTTNYT) from the V2 region of gp120 of HIV. D-[Ala]-Ser-Thr-Thr-Thr-Asn-Tyr-Thr-amide (DAPTA) is one of its a nalogue. DAPTA has been shown to resolve the psoriatic lesions. The me chanisms of action of peptide T for its therapeutic effect is not clea rly understood. Lymphomononuclear cells play an important roles in inf lammatory disease processes. Intraepidermal collection of lymphocytes is a unique feature of the inflammatory processes of psoriasis. It is believed that chemokine such as RANTES (C-C class) plays an important role for intraepidermal localization of the inflammatory infiltrates i n psoriasis, In order to study the mechanisms, we have analyzed the ef fects of DAPTA on monocyte and lymphocyte chemotaxis. Chemotaxis of ce lls was measured by using Boyden chamber. DAPTA inhibited significantl y the monocyte and lymphocyte chemotactic activity of RANTES (p < 0.00 5, < 0.001). Antichemotactic activities of peptide T analogue could be a possible explanation for its therapeutic efficacy in psoriasis. (C) 1998 International Society for Immunopharmacology. Published by Elsev ier Science Ltd.