- Other Names
- FceR1a, FceR1-a, FceR1-alpha, FceR1 alpha, high affinity IgE receptor, FCER1A, Fcε R1α, High affinity immunoglobulin epsilon receptor subunit alpha
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- Product Citations
High-affinity IgE receptor (FcεR1) plays a key role in IgE-mediated allergic immune responses. FcεR1 is a tetrameric receptor complex, which is composed of one α subunit (FcεR1α), one β subunit, and two γ subunits on mast cells and basophils. An alternate trimeric form composed of one α subunit (FcεR1α) and two γ subunits is expressed on mast cells, basophils, eosinophils and professional antigen-presenting cells. FcεR1α directly binds IgE with high affinity, while the β and γ chains are responsible for mediating intracellular signals. FcεR1α is a 50 kD transmembrane protein with an Ig superfamily structure which is primarily found on mast cells and basophils, but also expressed on many inflammatory cells including cutaneous Langerhans cells, dendritic cells, monocytes of patients with allergic disorders, platelets, bronchial epithelial cells, eosinophils produced in hypereosinophilic syndrome, and neutrophils of allergy-induced asthma patients. Binding of allergens to receptor-bound IgE leads to cell activation and the release of mediators (such as histamine) responsible for the manifestations of allergy. The same receptor also induces the secretion of important lymphokines.Product Details
- Human FcεR1α, amino acid Val26-Gln205 (Accession # P12319) with a C-terminal 6His tag was expressed in 293E cells.
- Molecular Mass
- The 189 amino acid recombinant protein has a predicted molecular mass of approximately 22 kD. The DTT-reduced and the non-reduced protein migrate at approximately 45 kD by SDS-PAGE. The predicted N-terminal amino acid is Val.
- >95%, as determined by Coomassie stained SDS-PAGE
- 0.22 µm filtered protein solution is in PBS
- Endotoxin Level
- Less than 0.1 EU per µg protein as determined by the LAL method
- 10 and 25 µg sizes are bottled at 200 µg/mL. 100 µg and larger sizes are lot-specific and bottled at the concentration indicated on the vial (please contact technical support for concentration, or use our Lookup tool if you have a lot number.)
- Storage & Handling
- Unopened vial can be stored between 2°C and 8°C for up to 2 weeks, at -20°C for up to six months, or at -70°C or colder until the expiration date. For maximum results, quick spin vial prior to opening. The protein can be aliquoted and stored at -20°C or colder. Stock solutions can also be prepared at 50 - 100 µg/mL in appropriate sterile buffer, carrier protein such as 0.2 - 1% BSA or HSA can be added when preparing the stock solution. Aliquots can be stored between 2°C and 8°C for up to one week and stored at -20°C or colder for up to 3 months. Avoid repeated freeze/thaw cycles.
- When human IgE is immobilized at 2 µg/mL, recombinant human FcεR1α binds in a dose-dependent manner. The EC50 range for this effect is 0.3 - 1.2 ng/mL. HRP anti-His Tag antibody (Cat. No. 652503) was used to detect the binding.
- Application Notes
BioLegend carrier-free recombinant proteins provided in liquid format are shipped on blue ice. Our comparison testing data indicates that when handled and stored as recommended, the liquid format has equal or better stability and shelf-life compared to commercially available lyophilized proteins after reconstitution. Our liquid proteins are verified in-house to maintain activity after shipping on blue ice and are backed by our 100% satisfaction guarantee. If you have any concerns, contact us at email@example.com.
- Covalently linked homodimer
Mast cells, basophils, cutaneuos Langerhans cells, dendritic cells, and monocytes of patients with allergic disorders, platelets, bronchial epithelial cells, eosinophils from hypereosinophilic syndrome, neutrophils of allergic asthmatic patients
- Bind IgE, trigger IgE-mediated allergic response
- Basophils, Dendritic cells, Eosinophils, Langerhans cells, Mast cells, Monocytes, Neutrophils
- Measured by its ability to bind human CD81
- Cell Type
- Basophils, Dendritic cells, Eosinophils, Macrophages, Mast cells
- Biology Area
- Immunology, Innate Immunity
- Molecular Family
- Soluble Receptors
- Antigen References
- Riske F, et al. 1991. J Biol Chem. 266:11245
- Gounni AS, et al. 2001. FASEB J. 15:940.
- Maurer D, et al. 1996. J Immunol. 157:607
- Maurer D, et al. 1994. J Exp Med. 179:745
- Campbell AM, et al. 1998. Am J Respir Cell Mol Biol. 19:92-7
- Gene ID
- 2205 View all products for this Gene ID
- View information about FcepsilonRIalpha on UniProt.org
- Does specific activity of a recombinant protein vary between lots?
Specific activity will vary for each lot and for the type of experiment that is done to validate it, but all passed lots will have activity within the established ED50 range for the product and we guarantee that our products will have lot-to-lot consistency. Please conduct an experiment-specific validation to find the optimal ED50 for your system.
- Have your recombinants been tested for stability?
Our testing shows that the recombinant proteins are able to withstand room temperature for a week without losing activity. In addition the recombinant proteins were also found to withstand four cycles of freeze and thaw without losing activity.
- How do you convert activity as an ED50 in ng/ml to a specific activity in Units/mg?
- Use formula Specific activity (Units/mg) = 10e6/ ED50 (ng/mL)
- How does the activity of your recombinant proteins compare to competitors?
We quality control each and every lot of recombinant protein. Not only do we check its bioactivity, but we also compare it against other commercially available recombinant proteins. We make sure each recombinant protein’s activity is at least as good as or better than the competition’s. In order to provide you with the best possible product, we ensure that our testing process is rigorous and thorough. If you’re curious and eager to make the switch to BioLegend recombinants, contact your sales representative today!
- What is the specific activity or ED50 of my recombinant protein?
The specific activity range of the protein is indicated on the product datasheets. Because the exact activity values on a per unit basis can largely fluctuate depending on a number of factors, including the nature of the assay, cell density, age of cells/passage number, culture media used, and end user technique, the specific activity is best defined as a range and we guarantee the specific activity of all our lots will be within the range indicated on the datasheet. Please note this only applies to recombinants labeled for use in bioassays. ELISA standard recombinant proteins are not recommended for bioassay usage as they are not tested for these applications.