Apolipoprotein B-48 (apoB48) is synthesized in the small intestine and becomes a component
of chylomicrons (CM). Apolipoprotein B-100 (apoB100) is synthesized in liver and becomes
a component of both very low density lipoprotein (VLDL) and low density lipoprotein
(LDL). To evaluate whether apoB100 is present in the human small intestine, we performed
immunohistochemical staining using anti-apoB100 monoclonal antibody (mAb). Jejunal
samples stained positive and the granular staining was noted in the supranuclear region
of epithelial cells. We also identified apoB100 expression in the epithelial cells
by immunoblotting and dot-blotting of PCR-amplified cDNA. In order to exclude submucosal
stroma contaminated with blood, we used isolated epithelium from human small intestine
obtained by a crypt isolation technique. The results indicate that not only apoB48,
but also apoB100 are expressed in human small intestine epithelium. The expression
of apoB100suggests that the dietary VLDL may be synthesized in human small intestine
epithehum and converted into LDL, which might play an important role in atherosclerosis.
Key words
Apolipoprotein B-100 - Small Intestine Immunohistochemical Staining - mRNA Editing
- Crypt Isolation Technique
