Faculty Research 1980 - 1989
Characterization of the major apolipoproteins secreted by two human hepatoma cell lines.
Document Type
Article
Publication Date
1981
Keywords
Cell-Line, Electrophoresis-Polyacrylamide-Gel, Hepatoma: me, se, Human, Liver-Neoplasms: me, se, SUPPORT-NON-U-S-GOVT, SUPPORT-U-S-GOVT-P-H-S
First Page
7089
Last Page
7096
JAX Source
Biochemistry 1981 Dec 8;20(25):7089-96
Grant
HL15895, CA18470, CA25875
Abstract
Two newly described human hepatoma derived cell lines, Hep G2 and Hep 3B [Knowles, B. B., Howe, C. C., & Aden, D. P. (1980) Science (Washington, D.C.) 209, 497-499], synthesize and secrete into the culture medium most of the major plasma apoproteins (apoA-I, apoA-II, apoB, apoC-II, apoC-III, and apoE). The synthesized apoproteins were identified by direct two-dimensional gel analysis of the culture medium or by two-dimensional analysis following purification of the apoproteins by ultracentrifugation or immunoprecipitation. We found that the apoA-I synthesized by both of the hepatoma cell lines consists of two isoproteins designated 2 and 3 which are more basic than the major plasma apoA-I isoproteins designated 4 and 5. The apoE synthesized by both cell lines is composed mainly of an array of isoproteins with increasingly higher molecular weights and lower isoelectric points as compared to those of the major apoE isoproteins found in plasma. These precursors of apoE are converted to the major apoE isoproteins upon treatment with Clostridium perfringens neuraminidase and represent sialo apoE isoproteins. ApoA-II, apoC-II, apoC-III-1, and apoC-III-2 correspond to the protein forms present in plasma. The human hepatoma cell lines (Hep G2 and Hep 3B) provide a unique model for studies of the regulation of human apoprotein and lipoprotein synthesis and catabolism.
Recommended Citation
Zannis VI,
Breslow JL,
SanGiacomo TR,
Aden DP,
Knowles BB.
Characterization of the major apolipoproteins secreted by two human hepatoma cell lines. Biochemistry 1981 Dec 8;20(25):7089-96