Abstract: A process for preparing a purified dimer of a bone-derived factor, which comprises subjecting an inclusion body of a bone-derived factor produced by genetic engineering to the following steps a) to e) in sequence: a) the step of treating an inclusion body of a bone-derived factor with a unfolding agent to prepare a solubilized monomer; b) the step of treating the solubilized monomer with a refolding solution to prepare a dimer; c) the step of subjecting the refolded dimer to ultrafiltration and solvent replacement; d) the step of subjecting the dimer solution prepared above to isoelectric precipitation; and e) the step of subjecting the isoelectrically precipitated dimer to reverse-phase chromatography.

Abstract: The present invention provides a method for exploring low molecular weight compounds which regulate positively or negatively the expression of the human BMP-2 with reference to a reporter activity by using 5′ upstream region gene containing the human BMP-2 promoter and an animal cell introduced with a recombinant expression vector which has been connected to an appropriate reporter gene. The low molecular weight susbtances and their derivatives obtained by the present method have morphogenetic activity and inhibiting activity for bone and cartilage through the expression of human BMP-2 and are useful as preventive or therapeutic agents for bone and cartilage diseases.