Expression of interleukin (IL)-8, regulated on activation, normal T cell expressed and secreted (RANTES), chemokine (C-X-C motif) ligand (CXCL) 1,2,3 (C = cysteine, X = any amino acid) and CXCL 16 in homogenate samples of lesional skin from 16 patients with pyoderma gangrenosum (PG) and six patients with Sweet's syndrome (SS). Six normal subjects (NS) served as controls. Numerical values represent signal intensity in a cytokine array assay.