Production of recombinant human osteoprotegrin from Trichoplusia ni cells and Bombyx mori larvae

Human osteoprotegrin (OPG) and its truncated mutant OPG-280 and lengthened mutant OPG-Fc were constructed and successfully expressed in Trichoplusia ni cells and Bombyx mori larvae. Native SDS-PAGE and Western blot analysis revealed that OPG-Fc is present as a homodimer in Tn cells or B. mori larvae compared with OPG and OPG-280. Furthermore, the hypocalcemic effect assay showed that truncation of the C-terminal 100 residues OPG does not abolish the biological activity and Fc can be helpful in forming the OPG homodimer with improved biological activity.