CCL4 and Pruritus: The aim of the study was to evaluate the immune component in the pathogenesis of PsO by analysing the serum concentrations of selected chemokines (CCL2/MCP-1, CCL3/MIP-1α, CCL4/MIP-1β, CCL5/RANTES, CCL17/TARC, CCL18/PARC, CCL22/MDC, CXCL8/IL-8) and their correlation with the severity of the disease, as well as pruritus intensity in the PsO population of northern Poland.