title: Identification of a synovial fibroblast-specific protein transduction domain for delivery of apoptotic agents to hyperplastic synovium.
abstract: Synovial hyperplasia, resulting in erosion of cartilage and bone, represents one of the major pathologies associated with rheumatoid arthritis. To develop an approach for efficient delivery of proteins or agents to synovium to induce targeted apoptosis of hyperplastic synovial tissue, we have screened an M13 peptide phage display library for synovial-specific transduction peptides. We identified a novel synovial-targeted transduction peptide, HAP-1, which is able to facilitate specific internalization of protein complexes into human and rabbit synovial cells in culture and rabbit synovial lining in vivo. HAP-1 and a non-tissue-specific cationic protein transduction domain, PTD-5, were fused to an antimicrobial peptide, (KLAK)(2), to generate two proapoptotic peptides termed DP2 and DP1, respectively. Administration of these peptides was able to induce apoptosis of rabbit and human synovial cells in culture, with DP2 inducing synovial cell-specific apoptosis. Intra-articular injection of DP1 and DP2 into arthritic rabbit joints with synovial hyperplasia induced extensive apoptosis of the hyperplastic synovium, while reducing the leukocytic infiltration and synovitis. These results suggest that proapoptotic peptides and, in particular, DP2 can be clinically useful for treatment of synovial hyperplasia, as well as inflammation. Moreover, the results demonstrate the feasibility of identifying tissue-specific transduction peptides capable of mediating efficient transduction in vivo.
authors.affiliation: Department of Molecular Genetics and Biochemistry, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261, USA.
authors.forename: Zhibao
authors.initials: Z
authors.lastname: Mi
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Lu
authors.forename: Jeffrey C
authors.initials: JC
authors.lastname: Mai
authors.forename: Bobby G
authors.initials: BG
authors.lastname: Ng
authors.forename: Guiqiang
authors.initials: G
authors.lastname: Wang
authors.forename: Eric R
authors.initials: ER
authors.lastname: Lechman
authors.forename: Simon C
authors.initials: SC
authors.lastname: Watkins
authors.forename: Hannah
authors.initials: H
authors.lastname: Rabinowich
authors.forename: Paul D
authors.initials: PD
authors.lastname: Robbins
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D001168:Arthritis / Q000139:chemically induced / Q000276:immunology; D017104:Bacteriophage M13; D002478:Cells, Cultured; D004705:Endocytosis / Q000187:drug effects; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects* / Q000473:pathology; D006801:Humans; D006965:Hyperplasia / Q000378:metabolism* / Q000473:pathology; D007375:Interleukin-1 / Q000008:administration & dosage / Q000494:pharmacology; D007962:Leukocytes / Q000276:immunology; D008969:Molecular Sequence Data; D009928:Organ Specificity; D010455:Peptides / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology*; D017434:Protein Structure, Tertiary; D011817:Rabbits; D013379:Substrate Specificity; D013583:Synovial Membrane / Q000166:cytology / Q000187:drug effects* / Q000473:pathology*; D013997:Time Factors; D001616:beta-Galactosidase / Q000235:genetics / Q000378:metabolism
chemical_list: D007375:Interleukin-1; D010455:Peptides; D001616:beta-Galactosidase