Apolipoprotein A & B
Apolipoprotein B is the primary apolipoprotein of chylomicrons, VLDL, IDL, and LDL particles (LDL – known commonly by the misnomer “bad cholesterol” when in reference to both heart disease and vascular disease in general), which is responsible for carrying fat molecules (lipids), including cholesterol, around the body (within the water outside cells) to all cells within all tissues.
While all the functional roles of ApoB within the LDL (and all larger) particles remains somewhat unclear, it is the primary organizing protein (of the entire complex shell enclosing/carrying fat molecules within) component of the particles and is absolutely required for the formation of these particles. What is also clear is that the ApoB on the LDL particle acts as a ligand for LDL receptors in various cells throughout the body (i.e., less formally, ApoB indicates fat carrying particles are ready to enter any cells with ApoB receptors and deliver fats carried within into the cells).
Though mechanisms only partially understood, high levels of ApoB, especially associated with the higher LDL particle concentrations, are the primary driver of plaques that cause vascular disease (atherosclerosis), commonly first becoming obviously symptomatic as heart disease, stroke & many other body wide complications after decades of progression.
- Sample of blood serum
- We perform the test daily separately or combined