Using cell-based assays, gene and protein expression analyses, along with nuclear magnetic resonance and molecular modeling-based investigations, we have demonstrated that a linear 18-residue peptide PIP-18 potently inhibits IL-1β-induced secretions of sPLA2 and matrix metalloproteinases (MMPs; 1, 2, 3, and 9) in RA synovial fibroblasts (SF), at protein and mRNA levels [11]. The gene discussed is IL1B; the disease is rheumatoid arthritis.