Compositions and methods for osteogenic gene therapy

摘要

The present disclosure provides compositions and methods for increasing bone growth and/or enhancing wound healing, for example, fracture repair. The disclosure provides recombinant nucleic acids useful for promoting bone growth. For example, the disclosure provides recombinant nucleic acids that encode a fibroblast growth factor-2 (FGF-2) analog. The disclosure also provides vectors and cells incorporating these nucleic acids, as well as FGF-2 analogs encode by them. The disclosure also provides a mouse system of bone marrow transplantation and methods for producing as well as methods for using the system. Methods for inducing division and/or inducing differentiation of a hematopoietic stem cell are also provided, as are methods for enhancing bone growth and/or wound repair (for example, fracture repair).

主权项

1. A method of identifying an agent that modulates bone growth, maintenance and repair, the method comprising:
harvesting at least one hematopoietic stem cell; transducing and expressing in the at least one mouse hematopoietic stem cell at least one heterologous nucleic acid comprising a polynucleotide sequence that encodes an osteogenic growth factor comprising a secretable analog of human fibroblast growth factor-2 (FGF-2) encoded by a nucleic acid sequence comprising in a 5′ to 3′ direction: a polynucleotide sequence that encodes a bone morphogenetic protein 2/4 (BMP2/4) hybrid secretion signal peptide sequence and a polynucleotide sequence that encodes a mature human FGF-2 polypeptide comprising a mutation that results in the substitution of an alanine for a cysteine in amino acid position 70 of FGF-2 and a mutation that results in the substitution of an asparagine for a cysteine in amino acid position 88 of FGF-2; introducing the at least one hematopoietic stem cell or a progeny thereof into an immunologically compatible mouse, wherein expression of the secretable analog of human FGF-2 produces an increase in serum level of FGF-2 as compared to immunologically compatible mice engrafted with hematopoietic stem cells transduced with the BMP2/4 hybrid secretion signal peptide sequence and a wild type FGF-2-control; administering an agent to the mouse; and screening for modulation of FGF-2 secretion, wherein an increase in FGF-2 secretion identifies an agent that increases bone growth.