A heparin-binding peptide (HBP) sequence from human heparin-binding epidermal growth factor-like growth factor (HB-EGF) was identified and was shown to exhibit cell penetration activity. This cell penetration induced an anti-inflammatory reaction in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages. HBP penetrated the cell membrane during the 10 min treatment and reduced the LPS-induced production of nitric oxide (NO), inducible nitric oxide synthase (iNOS), and cytokines (TNF-alpha and IL-6) in a concentration-dependent manner. Additionally, HBP inhibited the LPS-induced upregulation of cytokines, including TNF-alpha and IL-6, and decreased the interstitial infiltration of polymorphonuclear leukocytes in a lung inflammation model. HBP inhibited NF-kappa B-dependent inflammatory responses by directly blocking the phosphorylation and degradation of I kappa B alpha and by subsequently inhibiting the nuclear translocation of the p65 subunit of NF-kappa B. Taken together, this novel HBP may be potentially useful candidate for anti-inflammatory treatments and can be combined with other drugs of interest to transport attached molecules into cells. (C) 2012 Elsevier Inc. All rights reserved.