Recombinant Human SIRP alpha/CD172a mFc Chimera Protein, CF

When Recombinant Human CD47 Fc Chimera (4670-CD) is immobilized at 0.1 µg/mL (100 µL/well), Recombinant Human SIRP alpha /CD172a Mouse IgG2a Fc Chimera (Catalog # 10651-SA) binds with an ED50 of 5-40 ng/mL.

2 μg/lane of Recombinant Human SIRP alpha/CD172a mFc Chimera Protein (Catalog # 10651-SA) was resolved with SDS-PAGE under reducing (R) and non-reducing (NR) conditions and visualized by Coomassie® Blue staining, showing bands at 86-97 kDa and 172-194 kDa, respectively.

• Reactivity: Hu
• Applications: Bioactivity
• Format: Carrier-Free

Recombinant Human SIRP alpha/CD172a mFc Chimera Protein, CF Summary

• Additional Information: Mouse IgG2a Fc Tag
• Details of Functionality: Measured by its binding ability in a functional ELISA. When Recombinant Human CD47 Fc Chimera (Catalog # 4670-CD) is immobilized at 0.1 µg/mL (100 µL/well), Recombinant Human SIRP alpha /CD172a Mouse IgG2a Fc Chimera (Catalog # 10651-SA) binds with an ED50 of 5-40 ng/mL.
• Source: Chinese Hamster Ovary cell line, CHO-derived human SIRP alpha/CD172a protein
  

  Human SIRP alpha /CD172a (Gly27-Arg370) & (Glu31-Arg370) Accession # NP_542970.1	IEGRMDP	Mouse IgG2a (Glu98-Lys330)
  N-terminus		C-terminus

• N-terminal Sequence: Gly27 & Glu31
• Protein/Peptide Type: Recombinant Proteins
• Purity: >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.
• Endotoxin Note: <0.10 EU per 1 μg of the protein by the LAL method.

Applications/Dilutions

• Dilutions:
  • Bioactivity
• Theoretical MW: 65 kDa.
  Disclaimer note: The observed molecular weight of the protein may vary from the listed predicted molecular weight due to post translational modifications, post translation cleavages, relative charges, and other experimental factors.
• SDS-PAGE: 86-97 kDa, under reducing conditions

Packaging, Storage & Formulations

• Storage: Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
  • 12 months from date of receipt, -20 to -70 °C as supplied.
  • 1 month, 2 to 8 °C under sterile conditions after reconstitution.
  • 3 months, -20 to -70 °C under sterile conditions after reconstitution.
• Buffer: Lyophilized from a 0.2 μm filtered solution in PBS with Trehalose.
• Purity: >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.
• Reconstitution Instructions: Reconstitute at 500 μg/mL in PBS.

Notes

This product is produced by and ships from R&D Systems, Inc., a Bio-Techne brand.

Alternate Names for Recombinant Human SIRP alpha/CD172a mFc Chimera Protein, CF

• BIT
• BITbrain-immunoglobulin-like molecule with tyrosine-based activation motifs
• Brain Ig-like molecule with tyrosine-based activation motifs
• CD172 antigen-like family member A
• CD172a antigen
• CD172a
• Inhibitory receptor SHPS-1
• Macrophage fusion receptor
• MFR
• MFRtyrosine phosphatase SHP substrate 1
• MyD-1 antigen
• MYD1
• MYD-1
• P84
• protein tyrosine phosphatase, non-receptor type substrate 1
• PTPNS1
• SHP substrate 1
• SHPS1
• SHPS-1
• SHPS1CD172A
• signal-regulatory protein alpha
• Signal-regulatory protein alpha-1
• Signal-regulatory protein alpha-2
• Signal-regulatory protein alpha-3
• SIRP alpha
• SIRPA
• SIRPalpha
• Sirp-alpha-1
• SIRPalpha2
• Sirp-alpha-2
• Sirp-alpha-3
• SIRPtyrosine-protein phosphatase non-receptor type substrate 1

Background

Signal regulatory protein alpha (SIRP alpha, designated CD172a), also called SHPS-1 (SHP substrate 1) and previously, MyD-1 (Myeloid/Dendritic-1), is a monomeric ~90 kDa type I transmembrane glycoprotein that belongs to the SIRP/SHPS (CD172) family of the immunoglobulin superfamily (1-4). SIRPs are paired receptors, with similar extracellular domains but differing C-termini and functions (1, 2). The 503 amino acid (aa) human SIRP alpha contains a 342 aa extracellular domain (ECD), with one V-type, and two C1 type Ig domains, and three potential N glycosylation sites. It has a 110 aa cytoplasmic sequence with ITIM motifs that recruit tyrosine phosphatases SHP-1 and SHP-2 when phosphorylated (4). Human SIRP alpha has more than 40 described polymorphisms, including the prominent BIT (Brain Ig like molecule with Tyrosine-based activation motifs, also called SIRP alpha 2 or PTPNS) (5). One reported isoform lacks aa 1-101, which eliminates most of the V type Ig domain. Human SIRP alpha ECD shares 61%, 60%, 71%, 72% and 73% aa identity with mouse, rat, porcine, bovine and equine SIRP alpha, respectively; it shares 84% and 76% aa identity with human SIRP beta 1 and SIRP gamma, respectively (2). SIRP alpha is expressed mainly on myeloid cells, including macrophages, neutrophils, dendritic and Langerhans cells (3-6). It is also found on neurons, smooth muscle and endothelial cells (7-9). SIRP alpha shows adhesion to the ubiquitous CD47/IAP (integrin associated protein), while SIRP gamma binds more weakly and SIRP alpha 1 does not bind at all (1, 2). Mouse and human SIRP alpha -CD47 binding only cross-reacts for specific polymorphisms and influences engraftment of xenotransplanted stem cells (6, 10). SIRP alpha engagement generally produces a negative regulatory signal (4). Low SIRP alpha recognition of CD47, which occurs on aged erythrocytes or platelets or xenogenic cells, promotes clearance of CD47low cells from circulation (11, 13). SIRP alpha recognition of surfactants SP-A and SP-D in the lung can inhibit alveolar macrophage cytokine production (14). The CD47 integrin-SIRP alpha interaction is reported to promote macrophage fusion during osteoclastogenesis (15).

1. Barclay, A.N. & M.H. Brown (2006) Nat. Rev. Immunol. 6:457.
2. vanBeek, E.M. et al. (2005) J. Immunol. 175:7781.
3. Liu, Y. et al. (2005) J. Biol. Chem. 280:36132.
4. Kharitonenkov, A. et al. (1997) Nature 386:181.
5. Swissprot Accession # P78324.
6. Miyashita, M. et al. (2004) Mol. Biol. Cell 15:3950.
7. Wang, X.X. & K.H. Pfenninger (2005) J. Cell Sci. 119:172.
8. Maile, L.A. et al. (2003) Mol. Biol. Cell 14:3519.
9. Johansen, M.L. & E.J. Brown (2007) J. Biol. Chem. 282:24219.
10. Takenaka, K. et al. (2007) Nat. Immunol. 8:1313.
11. Ishikawa-Sekigami, T. et al. (2006) Biochem. Biophys. Res. Commun. 343:1197.
12. Olsson, M. et al. (2005) Blood 105:3577.
13. Ide, K. et al. (2007) Proc. Natl. Acad. Sci. USA 104:5062.
14. Gardai, S.J. et al. (2003) Cell 115:13.
15. Lundberg, P. et al. (2007) Biochem. Biophys. Res. Commun. 352:444.