title: Expression and characterization of a human BMP-7 variant with improved biochemical properties.
abstract: Bone morphogenetic protein-7 (BMP-7, OP-1) is a secreted growth factor that is predominantly known for its osteoinductive properties, though it has also been implicated as having a role in mammalian kidney development. Clinical efficacy of recombinant BMP-7 has been demonstrated in the treatment of orthopedic injuries through topical application. However, the pharmaceutical development of recombinant BMP-7 for systemic delivery has presented many challenges. Specifically, the expression level of recombinant mature BMP-7 protein in mammalian cells is very low, the molecule has poor solubility at neutral pH, and intracellular proteolytic processing events result in a secreted BMP-7 having multiple amino-termini, creating a heterogeneous mixture of proteins. Utilizing structural information, we have designed and generated a number of rational BMP-7 mutations that improved both expression levels in mammalian cells and solubility at neutral pH, while limiting the amino-terminal heterogeneity of the mature protein. Introduction of these mutations did not compromise BMP-7 in vitro bioactivity. This improved BMP-7 molecule is better suited for pharmaceutical development and clinical advancement for indications where systemic delivery may be required.
authors.affiliation: Molecular Discovery Technologies, Centocor Inc., 145 King of Prussia Road, Radnor, PA 19087, USA. BSwenck2@cntus.jnj.com
authors.forename: Bethany
authors.initials: B
authors.lastname: Swencki-Underwood
authors.forename: Juliane K
authors.initials: JK
authors.lastname: Mills
authors.forename: Joe
authors.initials: J
authors.lastname: Vennarini
authors.forename: Ken
authors.initials: K
authors.lastname: Boakye
authors.forename: Jinquan
authors.initials: J
authors.lastname: Luo
authors.forename: Steve
authors.initials: S
authors.lastname: Pomerantz
authors.forename: Mark R
authors.initials: MR
authors.lastname: Cunningham
authors.forename: Francis X
authors.initials: FX
authors.lastname: Farrell
authors.forename: Michael F
authors.initials: MF
authors.lastname: Naso
authors.forename: Bernard
authors.initials: B
authors.lastname: Amegadzie
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D016466:CHO Cells; D002460:Cell Line; D006224:Cricetinae; D003412:Cricetulus; D019281:Dimerization; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D050505:Mutant Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D009154:Mutation / Q000235:genetics; D011498:Protein Precursors / Q000737:chemistry / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D051381:Rats; D016212:Transforming Growth Factor beta / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: C525819:BMP7 protein, human; C525821:Bmp7 protein, rat; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins; D050505:Mutant Proteins; D011498:Protein Precursors; D016212:Transforming Growth Factor beta; D000469:Alkaline Phosphatase