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Analyte: Vascular Adhesion Molecule-1
Specimen Type: Serum, Inquire for additional option(s)
Optimum Volume: 0.5 mL
|6 days||1 month||18 months|
Reporting units: ng/mL
Biological or Clinical Significance:
Human Vascular Cell Adhesion Molecule-1 (VCAM-1) is a 100-110 kDa1 715 amino acid type I transmembrane glycoprotein typically characterized by the presence of seven C2-type immunoglobulin (Ig) domains. Its extracellular region is 674 amino acids in length, followed by a 22 amino acid transrnembrane segment and a 19 amino acid cytoplasmic tail. In the extracellular region, there are multiple N-linked glycosylation sites and each C2 domain is closed by a disulfide bridge. There is considerable interspecies VCAM-1 homology, with mouse and rat VCAM-1 showing approximately 75% amino acid identity to human VCAM-1. Notably, the short 19 amino acid cytoplasmic tail is absolutely conserved, mouse to human to rat. A number of variants of VCAM-1 are known to occur, all of which are likely the result of alternate gene splicing. In particular, a human six Ig domain molecule is known and in rabbits, an eight Ig domain form has been identified. There is also a three C2 domain, 43 kDa GPI-linked form of VCAM-1. Although it binds known VCAM-1 ligands (or co-receptors), its function is unclear. Cells known to express VCAM-1 include neurons, endothelial cells, smooth muscle cells, fibroblasts and macrophages.
Soluble VCAM-1 has been identified in culture supernates, blood and cerebrospinal fluid. The exact mechanism by which VCAM-1 is generated is unknown; it may, however, involve both proteolytic processing and alternate splicing.
Functionally, VCAM-1 binds to both a4ßD1 (VLA-4) and a4ß7 (LPAM-1) integrins. These integrins (or VCAM-1 ligands) are expressed on a variety of cells, with VLA-4 found on all leukocytes with the exception of neutrophils. Because of this, VCAM-1/VCAM-1 ligand interactions are undoubtedly key events in the rate and timing of leukocyte extravasation. Other roles proposed for VCAM-1 include the regulation of osteoclastogenesis via a cell-to-cell contact mechanism and the induction of sickle cell adherence to vascular endothelial cells during hypoxemia.
Principle of Test Method:
The VCAM-1 immunoassay is a solid phase ELISA that is designed to measure soluble VCAM in cell cutture supernates, serum and plasma.
1. Constans J, Conri C. Circulating markers of endothelial function in cardiovascular disease. Clin Chim Acta 2006; 368:33-47.
2. Jager A, van Hinsbergh VWM, Kostense PJ, Emeis JJ, Nijpeis G, Dekker JM, Heine RJ, Bouter LM, Sehouwer CDA. Increased levels of soluble vascular cell adhesion molecule 1 are associated with risk of cardiovascular mortality in type 2 diabetes: The Hoorn study. Diabetes 2000; 49:485-491.