CD11b (activation epitope) Monoclonal Antibody (CBRM1/5), eBioscience™, Invitrogen™

Description

• Description: The CBRM1/5 monoclonal antibody reacts with an activation-specific epitope of human Mac-1
• CBRM1/5 binds a subset of Mac-1 molecules on neutrophils and monocytes after stimulation with chemoattractants or phorbol esters but does not recognize Mac-1 on resting myeloid cells
• Through interactions with its ligands, Mac-1 participates in adhesive cell interactions
• The epitope recognized by this mAb localizes to the I domain on the alpha chain of Mac-1 very close to the ligand binding site in a region that is widely exposed
• CBRM1/5 blocks Mac-1 dependent adhesion to fibrinogen and ICAM-1 and inhibits chemoattractant-stimulated adhesion of eosinophils to the Intercellular Adhesion Molecule-1 (ICAM-1)
• It should be noted that low level activation may occur during processing of freshly drawn blood
• Therefore the CBRM1.5 antibody may exhibit some binding to Mac-1 in these unstimulated samples
• However, higher levels of Mac-1 expression are observed in activated samples when compared to unstimulated cells
• Applications Reported: The CBRM1/5 antibody has been reported for use in flow cytometric analysis, and immunoprecipitation
• CBRM1/5 has also been reported in blocking of CD11b function
• (Please use Functional Grade purified CBRM1/5, cat
• 16-0113, in functional assays.)
• Applications Tested: The CBRM1/5 antibody has been tested by flow cytometric analysis of resting and activated normal human peripheral blood cells
• CD11b (integrin alpha-M, ITGAM, integrin alpha-X, ITGAX) is a 165 kDa adhesion molecule that associates non-covalently with integrin beta-2 (CD18)
• The CD11b/CD18 heterodimeric complex is also known as integrin alpha-M beta-2, Mac-1, and CR3 (complement receptor 3)
• CD11b is expressed on the surface of monocytes/macrophages, granulocytes, activated lymphocytes, a subset of NK cells, a subset of dendritic cells, and microglia in the brain
• CD11b/CD18 functions as the receptor for ICAM-1 (CD54), ICAM-2 (CD102), ICAM-4 (CD242), CD14, CD50, CD23, heparin, iC3b, fibrinogen, and Factor X -these adhesions are critical for cell-cell and cell-matrix interactions
• CD11b is expressed on 8% of spleen cells, 44% of bone marrow cells, and less than 1% of thymocytes, and is commonly used as a microglial marker in nervous tissue
• The expression of CD11b increases during monocyte maturation and expression levels vary on tissue macrophages
• Further, peritoneal macrophages are reported to express higher levels of CD11b than splenic macrophages
• Diseases associated with CD11b dysfunction include systemic lupus erythematosus 6 and ITGAM-related susceptibility to systemic lupus erythematosus.