Early alterations in the postprandial VLDL1 apoB-100 and apoB-48
metabolism in men with strong heredity for type 2 diabetes.
was quantitated from plasma using a Western Blotting/Enhanced Chemiluminescence procedure described previously (23).
Leary's 15-minute lecture, "The Wonders of ApoB-48
ELISA," scheduled for 4:45 p.
The APOB gene is located on chromosome 2 and produces, via a unique mRNA editing process, two forms of apoB in circulating lipoproteins, apoB-48
and apoB-100 (3).
Triglycerides of dietary origin enter the circulation as chylomicrons, the largest of lipoprotein particles (80-1000 nm) packaged together with the truncated form of apolipoprotein B, apoB-48
, whereas fatty acids originating in the liver are secreted as VLDL (25-80 nm) with apoB-100.
Chylomicrons contain apoA, apoC, and apoB-48
and lack apoB-100.
Hypertriglyceridemia attributable to increased plasma concentrations of VLDL apolipoprotein (apo) B-100 and chylomicron apoB-48
is the most consistent lipid disorder in obesity (3, 4).
The human apoB gene (APOB) is located on chromosome 2, and the same gene produces two forms of apoB in circulating lipoproteins, apoB-48
Higher non-HDL cholesterol in the obese, a known correlate with apoB (27, 28), supports an increased apoB concentration, composed of apoB-100 and apoB-48
, both of which are increased in obese men (29).
Hypertriglyceridemia attributable to increased plasma concentrations of hepatic apolipoprotein (apo)4 B-100 and intestinal apoB-48
is the most consistent lipid disorder in visceral obesity and a risk factor for coronary artery disease (1, 2).
Because of the very high homology of hepatic apoB-100 with apoB-48
, quantification of apoB-48
by immunotechnology has been difficult.
Use of a monoclonal antibody that recognizes an epitope within the apoB-51 region distal to the C-terminus of apoB-48
(7) allows apo B-48-containing lipoproteins to be selectively enriched in the RLP fraction compared with the VLDL fraction isolated by the UC.