Description
General description
Low density lipoproteins are smaller than VLDL and IDL (26 nm) (MW approximately 3.5 million) and more dense (~1.04). The protein component of LDL is apolipoprotein B100. LDL contains 20-22% protein, 10-15% triglycerides, 20-28% phospholipids, 37-48% cholesteryl esters and 8-10% cholesterol.
Lipoprotein, low density (LDL) is synthesized by lipolysis and lipid transfer steps. They are formed from very low-density lipoprotein (VLDL) after uptake by LDL receptor in hepatocytes. LDL normal level of 130 mg/dL is desirable in human plasma. It is referred as bad cholesterol.
Application
Lipoprotein was used to study effect of the surface density of nano-segments immobilized on culture dishes on ex vivo expansion of hematopoietic stem and progenitor cells from umbilical cord blood. It was also used in the separation and cultivation of hematopoietic stem cells from umbilical cord blood by permeation through membranes with nano-segments.
Lipoprotein, low density from human plasma has been used:
in evaluating its anti-Langerhans cells (LC) differentiation activity in monocyte-derived Langerhans cells (MDLCs)
in the preparation of oxidized low-density lipoprotein (ox-LDL)
as a lipoprotein standard in quantifying embryonic cerebrospinal fluid (eCSF) from HH23 embryos by lipid staining
Biochem/physiol Actions
LDL and HDL transport both dietary and endogenous cholesterol in the plasma. LDL is the main transporter of cholesterol and cholesteryl esters and makes up more than half of the total lipoprotein in plasma. LDL is absorbed by the liver and other tissues via receptor mediated endocytosis. The cytoplasmic domain of the LDL receptor facilitates the formation of coated pits; receptor-rich regions of the membrane. The ligand binding domain of the receptor recognizes apo-B100 on LDL, resulting in the formation of a clathrin-coated vesicle. ATP-dependent proton pumps lower the pH inside the vesicle resulting dissociation of LDL from its receptor. After loss of the clathrin coat the vesicles fuse with lysozomes, resulting in peptide and cholesteryl ester enzymatic hydrolysis. The LDL receptor can be recycled to the cell membrane. Insulin, tri-iodothyronine and dexamethasome have shown to be involved with the regulation of LDL receptor mediated uptake.
The apolipoprotein component of the LDL particle interacts with extracellular matrix in arterial intima resulting in their retention. LDL is the major driver of atherosclerotic cardiovascular disease progression.
Preparation Note
Lyophilized from a solution of 0.15 M NaCl and 0.01% EDTA, pH 7.4
Disclaimer
RESEARCH USE ONLY. This product is regulated in France when intended to be used for scientific purposes, including for import and export activities (Article L 1211-1 paragraph 2 of the Public Health Code). The purchaser (i.e. enduser) is required to obtain an import authorization from the France Ministry of Research referred in the Article L1245-5-1 II. of Public Health Code. By ordering this product, you are confirming that you have obtained the proper import authorization.
