Recombinant Human FCAR/CD89 Protein, CF

• Reactivity: Hu
• Applications: Binding Activity
• Format: Carrier-Free

Recombinant Human FCAR/CD89 Protein, CF Summary

• Details of Functionality: Measured by its ability to bind human lgA in a functional ELISA with an estimated
  K_D <10 nM.
• Source: Mouse myeloma cell line, NS0-derived human FCAR/CD89 protein
  Gln22-Asn227, with a C-terminal 6-His tag
• Accession #: P24071
• N-terminal Sequence: No results obtained: Gln22 predicted
• Protein/Peptide Type: Recombinant Proteins
• Gene: FCAR
• Purity: >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining
• Endotoxin Note: <0.01 EU per 1 μg of the protein by the LAL method.

Applications/Dilutions

• Dilutions:
  • Binding Activity
• Theoretical MW: 24.3 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: 40-50 kDa, 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.
• Purity: >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining
• Reconstitution Instructions: Reconstitute at 100 μg/mL in sterile PBS.

Notes

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

Alternate Names for Recombinant Human FCAR/CD89 Protein, CF

• CD89 antigen
• CD89
• CD89IgA Fc receptor
• Fc alpha receptor
• Fc fragment of IgA, receptor for
• FCAR
• immunoglobulin alpha Fc receptor

Background

FCAR, also called Fc alpha RI or CD89, is a variably glycosylated 50-100 kDa myeloid-specific type I transmembrane (TM) Fc receptor for IgA that is a member of the multichain immune recognition receptor (MIRR) family (1-3). Human FCAR contains a 21 amino acid (aa) signal sequence and extracellular (ECD), TM and cytoplasmic domains of 206, 19 and 41 aa, respectively (4). Arg230 within the TM domain supports interaction with the ITAM-containing signaling subunit, FcR gamma , which contains a TM Asp (5-7). Two ECD C2-type Ig-like domains (EC1 and 2) are oriented at right angles (8). Up to two molecules of FCAR can bind one molecule of serum IgA via EC1 (8). Many splice variants have been reported, but only two have been identified as proteins (9, 10). The a.2 form, which lacks 22 aa just prior to the TM domain, is exclusively expressed in alveolar macrophages. The a.3 form lacks EC2. FCAR binds monomeric, polymeric and secretory IgA, but does not mediate the barrier function of secretory IgA in mucosal epithelium (1-3). Shedding and circulation of polymeric IgA/FCAR immune complexes has been reported (11). Circulating neutrophils, eosinophils, and monocytes express FCAR (12). Tissue expression of FCAR is mainly from neutrophils; FCAR is downregulated as monocytes differentiate to tissue macrophages (12). On neutrophils, a significant amount of FCAR lacks FcR gamma , but can still be endocytosed to early endosomes and recycled to the cell surface (5). Binding of serum IgA to FCAR is transient and anti-inflammatory, inhibiting IgG or IgE-induced degranulation (6). Sustained aggregation of FCAR results in inflammatory responses (6). FcR gamma signaling is required for these and for transport to late endosomes (5-7). Human FCAR shows 55-58% aa identity with rat, horse and cow FCAR. No ortholog occurs in mouse. FCAR structure resembles the KIR/ILT/LIR/MIR family more than other IgA receptors, including pIgR, Fc alpha /μR, asialoglycoprotein receptor (ASGR1) and transferrin receptor (TfR) (1-3).

1. Wines, B. D. and P. M. Hogarth (2006) Tissue Antigens 68:103.
2. Otten, M. A. and M. van Egmon (2004) Immunol. Lett. 92:23.
3. Montiero, R. C. and J. G. J. van de Winkel (2003) Annu. Rev. Immunol. 21:177.
4. Maliszewski, C. R. et al. (1990) J. Exp. Med. 172:1665.
5. Launay, P. et al. (1999) J. Biol. Chem. 274:7216.
6. Pasquier, B. et al. (2005) Immunity 22:31.
7. Shen, L. et al. (2001) Blood 97:205.
8. Herr, Y. et al. (2003) Nature 423:614.
9. Patry, C. et al. (1996) J. Immunol. 156:4442.
10. Togo, S. et al. (2003) FEBS Lett. 535:205.
11. van der Boog, P. J. M. et al. (2002) J. Immunol. 168:1252.
12. Hamre, R. et al. (2003) Scand. J. Immunol. 57:506.

Publications for FCAR/CD89 (3939-FA)(3)

Publications using 3939-FA

• Martinez-Martin N, Marcandalli J, Huang C, Arthur C, Perotti M, Foglierini M, Ho H, Dosey A, Shriver S, Payandeh J, Leitner A, Lanzavecchia A, Perez L, Ciferri C An Unbiased Screen for Human Cytomegalovirus Identifies Neuropilin-2 as a Central Viral Receptor. Cell, 2018-07-26;174(5):1158-1171.e19. 2018-07-26 [PMID: 30057110] (Biolayer Interferometry (BLI), Human)
• Lohse S, Meyer S, Meulenbroek L, Jansen J, Nederend M, Kretschmer A, Klausz K, Moginger U, Derer S, Rosner T, Kellner C, Schewe D, Sondermann P, Tiwari S, Kolarich D, Peipp M, Leusen J, Valerius T An Anti-EGFR IgA That Displays Improved Pharmacokinetics and Myeloid Effector Cell Engagement In Vivo. Cancer Res, 2015-12-03;76(2):403-17. 2015-12-03 [PMID: 26634925] (Surface Plasmon Resonance)
• Hatanaka T, Ohzono S, Park M, Sakamoto K, Tsukamoto S, Sugita R, Ishitobi H, Mori T, Ito O, Sorajo K, Sugimura K, Ham S, Ito Y Human IgA-binding peptides selected from random peptide libraries: affinity maturation and application in IgA purification. J Biol Chem, 2012-10-17;287(51):43126-36. 2012-10-17 [PMID: 23076147] (Surface Plasmon Resonance)

Bioinformatics

• Gene Symbol: FCAR
• Uniprot:
  • P24071()