Invitrogen™ Human ApoB100 ELISA Kit

Apolipoprotein B (apo B) in human plasma is a major protein of low density lipoproteins (LDL) with a molecular mass of approximately 260-500 kDa. Apolipoprotein B binds to specific receptors on cell membranes and is involved in removal of LDL and very low density lipoprotein (VLDL) cholesterol from circulation. Low-density lipoprotein (LDL) is the carrier protein for cholesterol in the blood. LDL binds to its receptor on the capillary walls and thereby mediates the uptake and clearance of cholesterol from the circulation. In atherosclerotic lesions oxidatively modified LDL is found and oxidized LDL is specifically recognized and ingested by macrophages via scavenger receptor A and CD36. Oxidized LDL may be a marker of atherosclerosis but the precise changes in oxidized LDL are not well described. MDA-oxidized LDL appear to be different from LDL oxidized by other means. Apolipoprotein B is mostly synthesized in the liver, and is a major apolipoprotein of very low density, intermediate density and low density lipoproteins (LDL) as well as being a major component of lipoprotein (a). Apolipoprotein B is a ligand for the LDL receptor and elevated levels are associated with premature atherosclerosis. Normal plasma apolipoprotein B levels are around 800mg/L. Apolipoprotein B occurs in plasma as two main isoforms, apoB-48 and apoB-100. The intestinal and the hepatic forms of Apolipoprotein B are encoded by a single gene from a single, very long mRNA. The two isoforms share a common N-terminal sequence. The shorter apoB-48 protein is produced after RNA editing of the apoB-100 transcript at residue 2180 (CAA->UAA), resulting in the creation of a stop codon, and early translation termination. Mutations in the Apolipoprotein B gene or its regulatory region cause hypobetalipoproteinemia, normotriglyceridemic hypobetalipoproteinemia, and hypercholesterolemia due to ligand-defective Apolipoprotein B, diseases affecting plasma cholesterol and Apolipoprotein B levels.