产品描述:
CD56, also known as neural cell adhesion molecule 1 (NCAM1), is a cell surface glycoprotein and member of the immunoglobulin superfamily that is involved in cellular adhesion and neural development.{60124,60125,60126} Alternative splicing of the NCAM1 pre-mRNA produces several isoforms, including two transmembrane isoforms of 180 and 140 kDa, NCAM-180 and NCAM-140, respectively, that differ in size of the cytoplasmic domain, and a 120 kDa isoform, NCAM-120, that lacks the cytoplasmic domain and is linked to the plasma membrane by a glycosylphosphatidylinositol (GPI) anchor.{60124} CD56 is composed of an extracellular N-terminal domain containing five immunoglobulin-like (Ig-like) domains and two fibronectin type III domains that mediate homophilic and heterophilic interactions, a transmembrane domain, and an intracellular C-terminal signaling domain.{60125,60127} It is used as a marker for neural and natural killer (NK) cells, but is also expressed by other immune cells, including monocytes, T cells, and dendritic cells (DCs), as well as tumor cells, in an isoform-dependent manner.{60124,60125,60127} CD56 is increased on NK cells by stimulation with IL-15 or IL-2 and correlates with upregulation of the NK cell activating receptors NKG2D, NKp30, and NKp46 and NK cell-mediated cytotoxicity.{60124,60127} Homophilic CD56 interactions induce neurite outgrowth of cerebellar neurons and promote NK cell-mediated tumor cell lysis in vitro.{60124,60125,60126,60127} The frequency of peripheral blood CD56bright NK cells is increased in patients with melanoma and associated with reduced overall survival.{60128} Cayman’s NCAM1/CD56 (human, recombinant) protein consists of 591 amino acids, has a calculated molecular weight of 66.1 kDa, and a predicted N-terminus of Leu20 after signal peptide cleavage. By SDS-PAGE, under reducing conditions, the apparent molecular mass of the protein is approximately 80-110 kDa due to glycosylation.