Recombinant Human Integrin alpha X beta 2 Protein, CF

Recombinant Human Integrin alpha X beta 2 Protein, CF Summary

Product Specifications

Product Datasheets

Carrier Free

CF stands for Carrier Free (CF). We typically add Bovine Serum Albumin (BSA) as a carrier protein to our recombinant proteins. Adding a carrier protein enhances protein stability, increases shelf-life, and allows the recombinant protein to be stored at a more dilute concentration. The carrier free version does not contain BSA.

In general, we advise purchasing the recombinant protein with BSA for use in cell or tissue culture, or as an ELISA standard. In contrast, the carrier free protein is recommended for applications, in which the presence of BSA could interfere.

Background: Integrin alpha X beta 2

Integrin alpha X beta 2, also called CD11c/CD18, p150/95 or complement receptor type 4 (CR4), is one of four beta 2 integrins. The non-covalent heterodimer of 150 kDa alpha X/CD11c and 95 kDa beta 2/CD18 integrin subunits is expressed on macrophages, dendritic cells and hairy cell leukemias, with lower amounts on other myeloid cells and activated B, NK and some cytotoxic T cells (1‑7). Like other integrins, alpha X beta 2 has multiple activation states (3). In the presence of divalent cations and "inside-out" signaling, alpha X beta 2 is fully active and extended. The alpha X vWFA or I-domain, which contains the adhesion sites, forms the N-terminal head region with the alpha X beta-propeller and the beta 2 vWFA domain (1, 8). In the inactive state, the heterodimer flexes in the center at the alpha X thigh and calf domains and beta 2 I-EGF domains, impeding access to adhesion sites (1). The 1088 aa human alpha X/CD11c ECD shares 70‑76% aa sequence identity with mouse, rat and canine alpha X while the 678 aa human beta 2/CD18 ECD shares 81‑83% aa sequence identity with mouse, rat, cow, dog, goat, sheep, and pig beta 2. Potential alpha X isoforms containing 719 and 725 aa (as compared to full-length 1163 aa alpha X) lack the vWFA domain and the N-terminus. Active alpha X beta 2 shares some adhesion partners with alpha M beta 2/CD11b/CD18, including complement opsonin fragment iC3b, ICAMs, vWF and fibrinogen, and is expressed on many of the same cells (4‑11). However, alpha M beta 2 activity is often constitutive, while alpha X beta 2 activity requires cell activation (4‑7). alpha X beta 2 also binds osteopontin, Thy-1, plasminogen, heparin, and proteins with abnormally exposed acidic residues (11‑16). The adhesion events are important for proliferation, degranulation, chemotactic migration, and phagocytosis of complement-opsonized particles (5, 6, 9, 11, 12, 16). Mutations of beta 2, especially in the vWFA domain, cause leukocyte adhesion deficiency (LAD-1) and susceptibility to bacterial infections (17).

Related Research Areas

• Adhesion Molecules
• Adhesion Molecules in Angiogenesis
• Adhesive Interactions in Allergy and Asthma
• B Cell Chemotaxis, Migration, and Adhesion
• Basophils
• Granulocyte Markers
• Integrins and Associated Molecules
• Monocyte Markers
• T Cell Migration/Adhesion