Human Fc epsilon  RI alpha Alexa Fluor® 750-conjugated Antibody

Applications

Please Note: Optimal dilutions should be determined by each laboratory for each application. General Protocols are available in the Technical Information section on our website.

Preparation and Storage

Background: Fc epsilon RI alpha

The alpha subunit of the high affinity IgE receptor (Fc epsilon  RI alpha or Fc epsilon RIA) is an IgE‑binding type I transmembrane glycoprotein of the multichain immune recognition (MIRR) family (1, 2). The receptor, Fc epsilon  RI, is a tetrameric complex of one alpha, one beta and two gamma subunits ( alpha beta gamma ₂) on mast cells and basophils (1). An alternate trimeric form ( alpha gamma ₂) is expressed on human, but not rodent, mast cells, basophils, eosinophils and professional antigen presenting cells (3). While the gamma subunit is essential for expression of Fc epsilon  RI alpha on the cell surface and for cell signaling, the beta subunit, when present, increases the halflife of the Fc epsilon  RI complex on the cell surface (3, 4). An isoform of the beta subunit, beta T, blocks processing of the alpha subunit and its cell surface expression (2, 3, 5). Human Fc epsilon  RI alpha cDNA encodes 257 amino acids (aa) including a 25 aa signal sequence, a 180 aa extracellular domain containing two Ig‑like domains that bind IgE and an endoplasmic reticulum retention motif, a 21 aa transmembrane domain with a charged amino acid (Asp219) that contributes to intracellular transport, and a 32 aa cytoplasmic sequence (1, 3, 6). Human Fc epsilon  RI alpha shares 50‑62% aa sequence identity with mouse, rat, equine, ovine, bovine, porcine and canine Fc epsilon  RI alpha. Binding of IgE alone increases surface expression of Fc epsilon  RI, while crosslinking of IgE/Fc epsilon  RI complexes by IgE ligands (allergens) initiates receptor internalization and signaling (2, 4, 5). Mast cell and basophil activation by IgE/Fc epsilon  RI crosslinking causes degranulation, releasing histamine, leukotrienes, prostaglandins, and other mediators of immediate‑type and late‑phase allergic reactions. Circulating autoantibodies that crosslink Fc epsilon  RI alpha are often found in patients with chronic urticaria (7). Fc epsilon  RI on human antigen presenting cells mediates uptake and processing of allergens for presentation by class II MHC (2, 3). Fc epsilon  RI expression on human DC and Langerhans cells is up‑regulated during allergic reactions (atopy) and correlates with serum IgE concentration (3).

Product Datasheets

Product Specific Notices

This product is provided under an agreement between Life Technologies Corporation and R&D Systems, Inc, and the manufacture, use, sale or import of this product is subject to one or more US patents and corresponding non-US equivalents, owned by Life Technologies Corporation and its affiliates. The purchase of this product conveys to the buyer the non-transferable right to use the purchased amount of the product and components of the product only in research conducted by the buyer (whether the buyer is an academic or for-profit entity). The sale of this product is expressly conditioned on the buyer not using the product or its components (1) in manufacturing; (2) to provide a service, information, or data to an unaffiliated third party for payment; (3) for therapeutic, diagnostic or prophylactic purposes; (4) to resell, sell, or otherwise transfer this product or its components to any third party, or for any other commercial purpose. Life Technologies Corporation will not assert a claim against the buyer of the infringement of the above patents based on the manufacture, use or sale of a commercial product developed in research by the buyer in which this product or its components was employed, provided that neither this product nor any of its components was used in the manufacture of such product. For information on purchasing a license to this product for purposes other than research, contact Life Technologies Corporation, Cell Analysis Business Unit, Business Development, 29851 Willow Creek Road, Eugene, OR 97402, Tel: (541) 465-8300. Fax: (541) 335-0354.

Related Research Areas

• Dendritic Cell Pathogen Recognition/Uptake
• Fc Receptors
• Granulocyte Markers
• Inflammatory/Monocyte-derived Dendritic Cells
• ITIM/ITAM Immunoreceptors and Related Molecules
• Leukocyte Receptors/Markers in Allergy and Asthma
• Macrophage Activation Markers
• Monocyte Markers