|CD11c||ITGAX (integrin αX), CR4, leukocyte suface antigen p150,95|
|Molecule Type||Antigen Expression||Molecular Weight|
Min / Max
|Non-lineage Restricted Molecule|
Type 1 glycoprotein
|145 / 145|
150 / 150
|CD11c expression is high on monocytes, macrophages and NK cells, moderate on granulocytes, and least on subsets of T and B cells. The level of expression on granulocytes can vary from low to high. CD11c is weakly expressed by CD3+ T lymphocytes and CD20+ B lymphocytes. Expression is low in sheep and rabbits, and moderate in cattle. The level of expression increases on B cells in B lymphoctotic cattle infected with bovine leukemia virus. It is also expressed on lymphoid cell lines including hairy cell leukemias. CD11c is used to detect myeloid cells in tissue studies.|
|MOLECULAR FAMILY NAME: Belongs to the integrin a chain family.|
CD11c is a single-pass type-1 a chain 1144 aa glycoprotein. It contains an 1081 aa extracellular region which contains an I-domain near the N-terminus, 7 tandem repeats that are modeled to resemble a b propeller fold.with 3 putative cation-binding motifs and 10 potential N-glycosylation sites, a 26 aa transmembrane domain and a 29 aa cytoplasmic region. The I-domain has not yet been crystallized and expressed in an isolated form but has been described to have ligand binding activity. It is expressed as a non-covalently linked heterodimer with CD18.
POST-TRANSCRIPTIONAL MODIFICATION: No information.
There are 10 potential N-glycosylation sites.
|CD11c/CD18 binds multiple ligands including the complement fragment iC3b, CD54 (ICAM-1), fibrinogen and bacterial lipopolysaccharide. It has also been reported that CD11c/CD18 binds denatured proteins. |
LIGANDS AND MOLECULES ASSOCIATED WITH CD11c
CD11c/CD18 binds similar ligands as CD11b/CD18 although not as well characterized.
|CD11/CD18 forms the integrin CD18 (p150,95) which is a type-4 complement receptor receptor CR4. CD11c functions in the adherence of neutrophils and monocytes to stimulated endothelium and is important in the phagocytosis of complement iC3b coated particles. CD11c/CD18 has been described to play important roles in cytotoxic T cell killing, and on neutrophil and monocyte adhesion to endothelium, although its ligands in these 2 cases have not been identified. CD11c has similar functions to CD11b/CD18 with which it cooperates. The major CD11/CD18 receptor is on tissue macrophages. An antibody against rabbit CD11c/CD18 has been reported to induce T cell aggregation. CD11c/CD18 is not expressed on leukocytes of patients with leukocyte adhesion deficiency (LAD). CD11c mediates cell-to-cell interactions in inflammation.|
BIOCHEMICAL ACTIVITY: No information.
DISEASE RELEVANCE AND FUNCTION OF CD11c IN INTACT ANIMAL
Leukocyte adhesion deficiency-type-1 (LAD-1) patients are CD11c-deficient.
|MOLECULAR INTERACTIONS -|
PROTEINS AND DNA ELEMENTS WHICH REGULATE TRANSCRIPTION OF CD11c
SUBSTRATES: No information.
ENZYMES WHICH MODIFY CD11c: No information.
CD11c/CD18 mediates leukocyte spreading onto protein-coated surfaces, a function suggestive of a role in cell survival, as has been already proposed for CD11b.
Database accession numbers
Revised June 25, 2008