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Recombinant Human CD300a/LMIR1 Fc Chimera Protein, CF

Catalog # 2640-LM | R&D Systems, Inc. a Bio-Techne Brand
Catalog #
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Key Product Details



Accession #

Structure / Form

Disulfide-linked homodimer





Product Specifications


Mouse myeloma cell line, NS0-derived human CD300a/LMIR1 protein
Human CD300a
Accession # Q9UGN4
N-terminus C-terminus


>90%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.

Endotoxin Level

<0.01 EU per 1 μg of the protein by the LAL method.

N-terminal Sequence Analysis


Predicted Molecular Mass

44.0 kDa (monomer)


60-80 kDa, reducing conditions


Measured by its ability to inhibit anti-CD3-induced proliferation of stimulated human T cells.
The ED50 for this effect is 1-5 µg/mL.
Optimal dilutions should be determined by each laboratory for each application.

Formulation, Preparation and Storage

Formulation Lyophilized from a 0.2 μm filtered solution in PBS.
Reconstitute at 100 μg/mL in PBS.

Reconstitution Buffer Available:
Size / Price
Shipping The product is shipped at ambient temperature. Upon receipt, store it immediately at the temperature recommended below.
Stability & 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.

Background: CD300a/LMIR1

LMIR1, also known as CD300a, CMRF-35H, IRp60, CLM-8, and MAIR-I, is a 60 kDa glycoprotein member of the immunoglobulin superfamily (1). Human LMIR1 consists of a 163 amino acid (aa) extracellular domain (ECD) with one Ig-like V-type domain, a 21 aa transmembrane segment, and a 98 aa cytoplasmic domain that contains three immunoreceptor tyrosine-based inhibitory motifs (ITIMs) and a non-canonical ITIM (2). Alternate splicing may generate additional isoforms that either lack the Ig-like domain or contain only the cytoplasmic domain. Within the ECD, human LMIR1 shares 40% and 43% aa sequence identity with mouse and rat LMIR1, respectively. In human, LMIR1 is expressed on peripheral blood eosinophils, mast cells, neutrophils, plasmacytoid dendritic cells, and various T cell subsets (3-7). Antibody cross‑linking of LMIR1 induces phosphorylation of tyrosine residues in the cytoplasmic domain. This leads to the recruitment of phosphatases SHIP, SHP-1, and SHP-2 and inhibition of NK cell, eosinophil, and mast cell activation (2, 3, 5-7). Cross‑linking of LMIR1 to other surface proteins such as SCF R or Fc epsilon RI on mast cells, Fc gamma RIIA on neutrophils, or CCR3 on mast cells and eosinophils inhibits downstream signaling from those receptors (5, 10‑12). LMIR1
cross‑linking also limits the in vivo activities of these cells with a subsequent reduction of allergic inflammation symptoms (4, 11, 12).


  1. Clark, G.J. et al. (2009) Trends Immunol. 30:209.
  2. Cantoni, C. et al. (1999) Eur. J. Immunol. 29:3148.
  3. Munitz, A. et al. (2006) Blood 107:1996.
  4. Bachelet, I. et al. (2005) J. Immunol. 175:7989.
  5. Alvarez, Y. et al. (2008) Mol. Immunol. 45:253.
  6. Ju, X. et al. (2008) Blood 112:1184.
  7. Clark, G.J. et al. (2007) J. Leukoc. Biol. 82:1126.
  8. Kumagai, H. et al. (2003) Biochem. Biophys. Res. Commun. 307:719.
  9. Yotsumoto, K. et al. (2003) J. Exp. Med. 198:223.
  10. Bachelet, I. et al. (2008) J. Immunol. 180:6064.
  11. Bachelet, I. et al. (2006) J. Allergy Clin. Immunol. 117:1314.
  12. Munitz, A. et al. (2006) J. Allergy Clin. Immunol. 118:1082.

Alternate Names

CD300a, CLM8, CMRF-35H, IGSF12, IRC1, IRC2, IRp60, LMIR1, MAIR-I, Mcipr1, NKRL, Pigr4

Entrez Gene IDs

11314 (Human); 217303 (Mouse)

Gene Symbol



Additional CD300a/LMIR1 Products

Product Documents for Recombinant Human CD300a/LMIR1 Fc Chimera Protein, CF

Certificate of Analysis

To download a Certificate of Analysis, please enter a lot number in the search box below.

Note: Certificate of Analysis not available for kit components.

Product Specific Notices for Recombinant Human CD300a/LMIR1 Fc Chimera Protein, CF

For research use only

Reconstitution Calculator

The reconstitution calculator allows you to quickly calculate the volume of a reagent to reconstitute your vial. Simply enter the mass of reagent and the target concentration and the calculator will determine the rest.

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