M-CSF, also known as CSF-1, is the primary regulator of macrophage survival, proliferation and differentiation and is essential for the survival and proliferation of osteoclast progenitors. M-CSF also primes and enhances macrophage killing of tumor cells and microorganisms, regulates the release of cytokines and other inflammatory modulators from macrophages, and stimulates pinocytosis.
Specifications and Use for R&D M-CSF
R&D M-CSF Source
• A DNA sequence encoding the N-terminal 230 amino acid residues of the extracellular domain of the mature mouse M-CSF protein sequence (residues 33 - 262 of the mouse M-CSF precursor) (Ladner, M.B. et al., 1988, Proc. Natl. Acad. Sci. USA 85:6706) was expressed in E. coli.
Molecular Mass of R&D M-CSF
• The N-terminal methionine form of the E. coli-expressed monomer of mouse M-CSF contains 231 amino acid residues and has a predicted molecular mass of approximately 26 kDa. The biologically active disulfide-linked homodimeric protein migrates as a 52 kDa protein in SDS-PAGE.
Purity of R&D M-CSF
• > 97%, as determined by SDS-PAGE and visualized by silver stain.
• < 1.0 EU per 1 μg of the cytokine as determined by the LAL method.
Activity of R&D M-CSF
• Measured in a cell proliferation assay using an M-CSF-dependent murine monocytic cell line, M-NFS-60 (Halenbeck, R. et al., 1989, Biotechnology 7:710 - 715).
• The ED50 for this effect is typically 0.5 - 1.5 ng/mL.
R&D M-CSF Formulation
• Lyophilized from a 0.2 μm filtered solution in PBS containing 50 μg of bovine serum albumin per 1 μg of cytokine.
R&D M-CSF Reconstitution
• It is recommended that sterile phosphate-buffered saline containing at least 0.1% human serum albumin or bovine serum albumin be added to the vial to prepare a stock solution of no less than 10 μg/mL of the cytokine.
Storage of R&D M-CSF
• Lyophilized samples are stable for up to twelve months at -20° C to -70° C.
• Upon reconstitution, this cytokine can be stored under sterile conditions at 2° - 8° C for one month or at -20° C to -70° C in a manual defrost freezer for three months without detectable loss of activity.
• Avoid repeated freeze-thaw cycles.