particleschylomicron

Particleschylomicron is not a standard term in lipidology. In current science, the large lipoprotein particle responsible for dietary fat transport is called the chylomicron. The hybrid term may appear in some nonstandard discussions to emphasize that the particle itself carries lipid cargo, rather than referencing cellular components. It is not part of established nomenclature.

Chylomicrons are formed in enterocytes of the small intestine. They contain triglycerides as the dominant core lipid, along with cholesteryl esters, phospholipids, and apolipoproteins, notably ApoB-48, with surface ApoC and ApoE acquired after secretion. Particle size ranges from roughly 75 to 1200 nanometers, making them the largest class of plasma lipoproteins.

Biogenesis involves microsomal triglyceride transfer protein (MTP) mediating transfer of lipids to ApoB-48; nascent particles are secreted into the lymphatic system via intestinal lacteals and eventually reach plasma. In the bloodstream, lipoprotein lipase (LPL) hydrolyzes triglycerides, yielding chylomicron remnants enriched in cholesteryl esters that are cleared by the liver through ApoE receptors.

Clinical and research relevance: Chylomicron metabolism is essential for dietary fat transport; defects in ApoB-48 production or MTP can cause abetalipoproteinemia or familial chylomicronemia syndrome. In research, chylomicron-like particles are studied to understand lipid transport; isolations by density gradient ultracentrifugation and analyses by electron microscopy or ApoB/ApoE measurements are common.

Note on terminology: The term particleschylomicron is not widely used in primary literature; readers should rely on standard terms 'chylomicron' for clarity.