Technical Data
Macrophage Stimulating Protein, C672A Mutation, Recombinant, Human (MSP)
Molecular Biology Storage: -20CShipping: Blue Ice
Macrophage stimulating protein (MSP), also known as HGF-like protein, and scatter factor-2, is a member of the HGF family of growth factors (1). MSP is secreted as an inactive single chain precursor (pro-MSP) that contains a PAN/APPLE-like domain, four kringle domains, and a peptidase S1 domain which lacks enzymatic activity (2). Human MSP shares 79% aa sequence identity with mouse MSP and 44% aa sequence identity with human HGF. Pro-MSP is secreted by hepatocytes under the positive and negative control of CBP in complex with either HNF-4 or RAR, respectively (3). Circulating pro-MSP is proteolytically cleaved in response to tissue injury to yield biologically active disulfide linked heterodimers consisting of a 45-62kD alpha and a 25-35kD beta chain (4, 5). Pro-MSP can be activated by MT-SP1, a transmembrane protease that is expressed on macrophages and is upregulated in many cancers (6). Heterodimeric MSP, as well as the isolated beta chain, binds to MSP R/Ron with high-affinity, although only heterodimeric MSP can induce receptor dimerization and signaling (7, 8). MSP induces macrophage and keratinocyte proliferation and osteoclast activation (9, 10). It also inhibits LPS- or IFN-induced iNOS and IL-12 expression by macrophages and prevents apoptosis of epithelial cells separated from the ECM (11, 12). The substitution of cysteine 672 (in the beta chain) with alanine significantly increases the bioactivity of recombinant MSP, apparently by limiting incorrect disulfide bond formation between the alpha and beta chains (13).

Bioloigical Activity: Measured by its ability to activate MSP R/Ron in a human breast cancer cell line, MDA-MB-453. 80ng/mL of the rhMSP (C672A) significantly induces phosphorylation of MSP R/Ron.

Storage and Stability: Lyophilized powder may be stored at -20C. Reconstitute to nominal volume by adding PBS, 0.1% BSA or HSA. Aliquot and store at -20C. Reconstituted product is stable for 12 months at -20C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.
Source: Chinese Hamster Ovary (CHO) cells
Purity: 95, as determined by SDS-PAGE and visualized by silver stain. Endotoxin: 1.0 EU/1ug.
Form: Supplied as a lyophilized powder in PBS, with 50ug BSA per 1ug of cytokine. Reconstitute with PBS, 0.1% BSA or HSA to 0.01mg/ml.

Important Note: This product as supplied is intended for research use only, not for use in human, therapeutic or diagnostic applications without the expressed written authorization of United States Biological.
1. Wang, M.-H. et al., 2002, Scand. J. Immunol.56:545. 2. Han, S. et al., 1991, Biochemistry 30:9768. 3. Muraoka, R.S. et al., 1999, Endocrinology 140:187. 4. Wang, M.-H. et al., 1996, J. Clin. Invest. 97:720. 5. Nanney, L.B. et al., 1998, J. Invest. Dermatol. 111:573. 6. Bhatt, A.S. et al., 2007, Proc. Natl. Acad. Sci. 104:5771. 7. Wang, M.-H. et al., 1997, J. Biol. Chem. 272:16999. 8. Danilkovitch, A. et al., 1999, J. Biol. Chem. 274:29937. 9. Wang, M.-H. et al., 1996, Exp. Cell Res. 226:39.10. Kurihara, N. et al., 1998, Exp. Hematol. 26:1080. 11. Morrison, A.C. et al., 2004, J. Immunol. 172:1825. 12. Liu, Q.P. et al., 1999, J. Immunol. 163:6606. 13. Wahl, R.C. et al., 1997, J. Biol. Chem. 272:15053.

Intended for research use only. Not for use in human, therapeutic, or diagnostic applications.