A new conformational neutralizable epitope is created on heptocyte growth factor (HGF), when it interacts with its receptor, cMet. By immunizing rabbits with HGF-cMet complex, we successfully generated a monoclonal antibody (SFN68) that inhibits HGF-cMet interaction, and blocks the biological function mediated by HGF. To define the epitope, we screened out an epitope-mimicking peptide, KSLSRHDHIHHH, from a phage display of combinatorial peptide library. In molecular mimicry this peptide bound to cMet and inhibited HGF-cMet interaction. No humoral response was induced to this epitope-mimicking peptide when immunization was done with HGF alone. (c) 2006 Elsevier Inc. All rights reserved.