MCP-1 in psoriatic patients: effect of biological therapy

Background: Monocyte chemoattractant protein-1 (MCP-1) is a chemokine locally and systemically augmented in psoriasis. A single nucleotide polymorphism in MCP-1 promoter region -2518A -> G is associated with higher gene expression. Objective: The aim was to evaluate MCP-1 plasma level in psoriatic patients and to relate any association in plasmatic and cutaneous MCP-1 with clinical improvement due to biological drugs. Methods: Blood samples were obtained from: (i) 30 Caucasian patients with psoriasis and 10 controls, for determining MCP-1 plasma concentrations and -2518A -> G polymorphism occurrence, (ii) 16 psoriatic patients treated by anti-tumor necrosis factor-alpha (TNF-alpha) adalimumab/etanercept or by anti-CD-11 efalizumab, before and after 2 months of treatment. Moreover, biopsies were performed on lesional skin of five patients treated with anti-TNF-alpha. MCP-1 plasma concentration and cutaneous expression were determined by ELISA and qRT-PCR. Results: MCP-1 plasma level was significantly increased in psoriatic patients. -2518A -> G polymorphism was similarly distributed in patients and controls and unrelated to MCP-1 plasma level or to Psoriasis Area and Severity Index. All patients receiving biological drugs showed significant clinical improvement. Anti-TNF-alpha therapy moderately reduced MCP-1 plasma concentration and robustly decremented MCP-1 expression in lesional skin. Conclusion: MCP-1 should be a potential local inflammatory marker in psoriatic patients to assess disease severity and anti-TNF-alpha treatment efficacy.