Key Product Details
|Human Integrin alphaL
Accession # P20701
|Human Integrin beta2
Accession # P05107
N-terminal Sequence Analysis
Predicted Molecular Mass
When 5 x 104 cells/well are added to Integrin alphaL beta2-coated plates (5 µg/mL, 100 µL/well), 60‑80% of the cells will adhere after 1 hour at 37° C in the presence of 1 mM MnCl2.
Formulation, Preparation and Storage
|Formulation||Lyophilized from a 0.2 μm filtered solution in PBS.|
Reconstitute at 100 μg/mL in sterile PBS.
|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.
Background: Integrin alpha L beta 2
Integrin alphaL beta2, also called LFA-1, is one of three beta2 integrin adhesion proteins. The non-covalent heterodimer of 180 kDa alphaL/CD11a and 95 kDa beta2/CD18 integrin subunits is expressed on virtually all leukocytes (1-3). The ligand binding site of LFA-1 is in the N-terminal head region, formed by an interaction of the vWFA (I, I‑like) domains from each subunit, and the alphaL beta-propeller structure (3-5). The alphaL subunit contains domains termed thigh, calf-1 and calf-2, while the beta2 subunit contains a PSI (plexin-semaphorin-integrin) region and four cysteine-rich I-EGF folds (5, 6). Each subunit has a transmembrane sequence and a short cytoplasmic tail connected to the cytoskeleton. Upon activation by “inside-out” signaling, clustering, or Mg2+ or Mn2+ binding to metal ion-dependent adhesion sites (MIDAS) within the vWFA domains, the molecule unfolds from its inactive, “closed” conformation to expose ligand binding sites (3, 6-9). Active alphaL beta2 binds ICAM-1/CD54, ICAM-2, ICAM‑3 and JAM‑A (1, 10-12). The adhesion stabilizes interactions between T cells and antigen-presenting cells, decreases the T cell activation threshold, and facilitates leukocyte transendothelial migration to sites of inflammation (12-14). A constitutively active construct severely impairs immune responses, demonstrating that both activation and de-activation are important (14). Mutations of beta2, especially in the vWFA domain, cause leukocyte adhesion deficiency (LAD-1) and susceptibility to bacterial infections (15). The 1088 amino acid (aa) human alphaL/CD11b ECD is 73-74% aa identical to mouse and rat, and 79-80% aa identical to bovine, porcine, ovine, goat and canine alphaL ECD. A second human alphaL isoform has 53 aa inserted after aa 954 in the ECD. The 678 aa human beta2/CD18 ECD shares 81-83% aa sequence identity with mouse, rat, bovine, canine, goat, ovine, and porcine beta2 ECD.
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Entrez Gene IDs
Product Specific Notices for Recombinant Human Integrin alpha L beta 2 Protein, CF
For research use only