Human low-density lipoproteins (LDL) are large protein complexes (∼500,000 Da) that bind to vertebrate cell surfaces Binding of specific receptors leads to the delivery of cholesterol through receptor-mediated endocytosis—labeled LDL complexes are a useful tool to study this phenomenon. These experiments typically involve growing cells with the addition of fluorescently labeled LDL and analyzing them by microscopy or flow cytometry. Alternatively, fluorescently labeled LDL can be injected into test animals, and the distribution of label can be analyzed after a specified period of time. We offer one unlabeled LDL and two types of labeled LDL: LDL containing unmodified apolipoproteins (for studying normal cholesterol transport and endocytosis) and LDL containing acetylated (Ac) apolipoproteins (for studying specific Cell types that express this acetylated LDL receptor (i.e., endothelial cells and microglia)).

LDL Specification:

•Marking (Ex/Em): Dil (554/571)
• Acetylation: No
• Amount: 200 µL (1.0 mg/mL)

Continuous preparation of fresh LDL
We prepare LDL and AcLDL products from fresh human plasma approximately every two months. Non-acetylated LDL products ship within two weeks of their preparation. All Acetylated LDL products are available on an ongoing basis.

Non-acetylated vs. acetylated LDL
LDL containing unmodified apolipoproteins can be used to study normal cholesterol delivery and endocytosis. If the lysine residues of the apolipoprotein of LDL are acetylated, the LDL complex no longer binds to the LDL receptor but is instead bound by endothelial cells and small cells that possess "scavenger" receptors specific for this modified form. Glial cell uptake.

Major Applications of Labeled LDL
Some of the applications of LDL complexes include:
• Enumeration of cell surface LDL receptors and analysis of their movement after endocytosis and Aggregation
• Quantify LDL receptor activity in fibroblasts (alternative to radiolabeled LDL assay)
• Study LDL expression in different cell lines and identify LDL receptor defects

Only research use. Not for use in the treatment or diagnosis of any animal or human being.