Catalogue

Background
Integrin, alpha L (antigen CD11A (p180), lymphocyte function-associated antigen 1; alpha polypeptide), also known as ITGAL, is a human gene which functions in the immune system. It is involved in cellular adhesion and costimulatory signaling. ITGAL encodes the integrin alpha L chain. Integrins are heterodimeric integral membrane proteins composed of an alpha chain and a beta chain. This I-domain containing alpha integrin combines with the beta 2 chain (ITGB2) to form the integrin lymphocyte function-associated antigen-1 (LFA-1), which is expressed on all leukocytes. LFA-1 is part of the family of leukocyte integrins that are recognised by their common β-chains (CD18). LFA-1 also has a distinct α-chain (CD11a). LFA-1 is expressed on lymphocytes, monocytes and granulocytes; it has been shown that LFA-1 contributes to the adhesion reaction of these cells. Blocking experiments with anti-LFA monoclonal antibodies demonstRated that LFA-1 inhibits the adhesion step effector and target cells in cytotoxic T lymphocyte, natural killer and lectin dependent cytotoxicity. LFA-1 is involved in recruitment to the site of infection. It binds to ICAM-1 on antigen-presenting cells and functions as an adhesion molecule. LFA-1 is the first to bind T-cells to antigen-presenting cells and initially binds weakly. A signal from the T-cell receptor and/or the cytokine receptor changes the conformation and prolongs the cell contact, allowing the T-cell to proliferate. A unique antibody NKI(SPV)-L16, reacting with the a-chain of the human leukocyte function-associated Ag- 1 (LFA- 1) has been made available. This antibody stimulates homotypic cell-cell interactions in a manner very similar to 12-0-tetradecanoyl-phorbol1-3 -acetate (TPA), in contrast to other anti-LFA-1 mAb which inhibit cell aggregation. Immunoprecipitation and enzyme digestion studies revealed that NKI-L16 recognizes a unique epitope on the cy-chain of LFA-1,most likely situated close to the transmembrane segment of the molecule. It is hypothesized that NKI-L16 or TPA can cause the LFA-1 molecule to convert from an inactive to an active configuRation, thereby permitting binding of LFA-1 1 to its natural ligand. This mAb directed, in contrast to other anti-LFA-1 antibodies, stimulates rather than inhibits homotypic cell aggregate formation, but does not affect cell prolifeRation.

Source
The antibody was raised by immunization of Balb/c mice with monocytes. The unique activation dependent epitope of the SPV-L16 antibody on the a-chain of LFA-1 is relatively insensitive to trypsin treatment and thus most likely loCated close to the transmembrane segment of the protein.

Product
Each vial contains 100 ul 1 mg/ml purified monoclonal antibody in PBS containing 0.09% sodium azide.

Formulation: Each vial contains 100 ul 1 mg/ml purified monoclonal antibody in PBS containing 0.09% sodium azide.

Specificity
This antibody recognizes an activation epitope of CD11a and has been essential to define inside-out signaling of intergrin. Homotypic cell aggregate formation is stimulated (see also Background).

Applications
NKI(SPV)-L16 is useful for flow cytometry and, immunoprecipitation. Optimal antibody dilution should be determined by titration.

Storage
The antibody is shipped at ambient temperature and may be stored at +4°C. For prolonged storage prepare appropriate aliquots and store at or below -20°C. Prior to use, an aliquot is thawed slowly in the dark at ambient temperature, spun down again and used to prepare working dilutions by adding sterile phosphate buffered saline (PBS, pH 7.2). Repeated thawing and freezing should be avoided. Working dilutions should be stored at +4°C, not refrozen, and preferably used the same day. If a slight precipitation occurs upon storage, this should be removed by centrifugation. It will not affect the performance or the concentration of the product.

Caution
This product is intended FOR RESEARCH USE ONLY, and FOR TESTS IN VITRO, not for use in diagnostic or therapeutic procedures involving humans or animals. It may contain hazardous ingredients. Please refer to the Safety Data Sheets (SDS) for additional information and proper handling procedures. Dispose product remainders according to local regulations.This datasheet is as accurate as reasonably achievable, but our company accepts no liability for any inaccuracies or omissions in this information.

References
1. Keizer GD, Visser W, Vliem M, Figdor CG. A monoclonal antibody (NKI-L16) directed anti a unique epitope on the alpha chain of Human leukocyte function-associated antigen 1 induces homotypic cell-cell interactions. J. Immunol. 140: 1393-1400, 1988. 2. Van Kooyk Y, Weder P, Hogervorst F, Verhoeven AJ, van Seventer G, te Velde AA, Borst J, Keizer GD, Figdor CG. Activation of LFA-1 through a Ca2(+)-dependent epitope stimulates lymphocyte adhesion. J Cell Biol. 112: 345-54, 1991. 3. Van Kooyk Y, van de Wiel-van Kemenade P, Weder P, Kuijpers TW, Figdor CG. Enhancement of LFA-1-mediated cell adhesion by triggering through CD2 or CD3 on T lymphocytes. Nature. 342:811-813, 1989.

Protein Reference(s)

Database Name: UniProt

Accession Number: P20701

Safety Datasheet(s) for this product: