The cDNA encoding bovine macrophage colony-stimulating factor (M-CSF) was cloned and recombinant bovine M-CSF (rbM-CSF) in its dimeric form was expressed by using a recombinant baculovirus/insect cell system. The predicted amino acid sequence of rbM-CSF shared 75.3 and 65.9 % similarity with the sequence for human and murine M-CSFs, respectively. The biological activity of rbM-CSF was confirmed by the colony forming assay using mouse bone marrow cells. SDS-PAGE under reducing condition showed that the molecular weight of rbM-CSF was approximately 34 kDa. On the other hand Western blot analysis under non-reducing condition revealed that this rbM-CSF was secreted in dimeric form into the cell supernatant.
(Lab. of Molecular Pathology, Department of Immunology)
