CD163, Recombinant, Human (Hemoglobin/Haptoglobin Complex Receptor, M130 antigen, Ber-Mac3, Ki-M8, SM4)

CD163, previously called M130 or p155, is a 130-160kD type I transmembrane glycoprotein that belongs to group B of the cysteine-rich scavenger receptor family (1-3). It is essential for clearance of hemoglobin-haptoglobin (Hb-Hp) complexes in the liver, spleen and circulation (4). The human CD163 contains a 41 amino acid (aa) signal sequence, a 1009 aa extracellular domain (ECD) with 9 scavenger receptor cysteine-rich (SRCR) domains, a 22 aa transmembrane segment, and a 39-84 aa cytoplasmic region (1). The third SRCR domain is crucial for calcium-dependent binding of hemoglobin/haptoglobin complexes (3). Three splice forms (isoforms 2, 3 and 4) vary within their intracellular regions (1, 5), while one isoform (# 4) also has a 34 aa insert between SRCR domains 5 and 6 within the ECD. While all are expressed, isoform 3 is most abundant, being generally expressed on the cell surface and most active in endocytosis (5). A ~130kD soluble form of human CD163 (sCD163) is assumed to contain virtually all of the ECD, which shares 74%, 75%, 84%, 86%, 86% and 87% aa identity with mouse, rat, bovine, equine, porcine and canine CD163 ECD, respectively (6, 7). It is released from the cell surface by proteolysis after oxidative stress or inflammatory stimuli, including bacterial endotoxins and activation of the Toll-like receptors TLR2 or TLR5 (7-10). Expression of CD163 is constitutive, and induced by glucocorticoids, IL-10, IL-6 or endotoxin on circulating monocytes, tissue macrophages, and at low levels on monocyte-derived dendritic cells (1, 2, 11, 12). In addition to clearing Hb-Hp complexes, CD163 is also a scavenger receptor for free Hb (if Hp is depleted) and TWEAK (TNF-like weak inducer of apoptosis), and can function as an erythroblast adhesion receptor (4, 13-15).\n\nSource: DNA sequence encoding the extracellular domain of human CD163 (Gly 41-Ser 1045; Accession # CAA80543) was linked to a C-terminal 10 histidine tag and expressed in a mouse myeloma cell line, NS0.\nMolecular Mass\n\nDefinition: Measured by its ability to bind Haptoglobin/Hemoglobin (Hp/Hb) complexes.\n\nApplications: \nSuitable for use Western Blot. Other applications not tested.\n\nRecommended Dilution:\nWestern Blot: 110kD migrates as an ~ 160kD protein in SDS-PAGE under reducing conditions. \nOptimal dilutions to be determined by the researcher.\n\nStorage and Stability:\nLyophilized powder may be stored at 4 degrees C for short-term only. Reconstitute to nominal volume by adding sterile PBS and store at -20 degrees C. Reconstituted product is stable for 12 months at -20 degrees C. 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.

Prices direct from United States Biological

Quick response times

Exclusive Biosave savings/discounts

SPECIFICATIONS

Catalog Number

C2548-90E

Size

50ug

Applications

WB

Reactivities

Hum

Form

Supplied as a lyophilized powder in PBS. Reconstitute with sterile PBS to (same/more than) 0.1mg/ml.

Purity

(same/more than) 95%, as determined by SDS-PAGE under reducing conditions and visualized by silver stain.\nEndotoxin (same/less than) 1EU.

References

1. Law, S.K.A. et al. (1993) Eur. J. Immunol. 23:2320. 9. Weaver, L.K. et al. (2006) J. Leukoc. Biol. 80:26.\n2. Sulahian, T.H. et al. (2000) Cytokine 12:1312. 10. Timmerman, M. & P. Hogger (2005) Free Radic. Biol. Med. 39:98.\n3. Madsen, M. et al. (2004) J. Biol. Chem. 279:51561. 11. Buechler, C. et al. (2000) J. Leukoc. Biol. 67:97.\n4. Kristiansen, M. et al. (2001) Nature 409:198. 12. Pulford, K.A. et al. (1989) J. Clin. Pathol. 42:414.\n5. Nielsen, M.J. et al. (2006) J. Leukoc. Biol. 79:837. 13. Schaer, D.J. et al. (2006) Blood 107:373.\n6. Moller, H.J. et al. (2002) Blood 99:378. 14. Bover, L.C. et al. (2007) J. Immunol. 178:8183.\n7. Droste, A. et al. (1999) Biochem. Biophys. Res. Commun. 256:110. 15. Fabriek, B.O. et al. (2007) Blood 109:5223.\n8. Hintz, K. A. et al. (2002) J. Leukoc. Biol. 72:711.