HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: M300059-JLR200v1 44/9/1698    most recent Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Siggins, S. Articles by Ehnholm, C. Search for Related Content PubMed PubMed Citation Articles by Siggins, S. Articles by Ehnholm, C. Social Bookmarking                      What's this?

Journal of Lipid Research, Vol. 44, 1698-1704, September 2003
Copyright © 2003 by American Society for Biochemistry and Molecular Biology

PLTP secreted by HepG2 cells resembles the high-activity PLTP form in human plasma

Sarah Siggins, Matti Jauhiainen, Vesa M. Olkkonen, Jukka Tenhunen and Christian Ehnholm¹

National Public Health Institute, Department of Molecular Medicine, Biomedicum, P.O. Box 104, FIN-00251 Helsinki, Finland

¹ To whom correspondence should be addressed. e-mail: christian.ehnholm{at}ktl.fi

Plasma phospholipid transfer protein (PLTP) is an important regulator of plasma HDL levels and HDL particle distribution. PLTP is present in plasma in two forms, one with high and the other with low phospholipid transfer activity. We have used the human hepatoma cell line, HepG2, as a model to study PLTP secreted from hepatic cells. PLTP activity was secreted by the cells into serum-free culture medium as a function of time. However, modification of a previously established ELISA assay to include a denaturing sample pretreatment with the anionic detergent sodium dodecyl sulphate was required for the detection of the secreted PLTP protein. The HepG2 PLTP could be enriched by Heparin-Sepharose affinity chromatography and eluted in size-exclusion chromatography at a position corresponding to the size of 160 kDa. PLTP coeluted with apolipoprotein E (apoE) but not with apoB-100 or apoA-I. A portion of PLTP was retained by an anti-apoE immunoaffinity column together with apoE, suggesting an interaction between these two proteins. Furthermore, antibodies against apoE but not those against apoB-100 or apoA-I were capable of inhibiting PLTP activity.

These results show that the HepG2-derived PLTP resembles in several aspects the high-activity form of PLTP found in human plasma.

Abbreviations: apoA-I, apolipoprotein A-I; HRP, horseradish peroxidase; IgG, immunoglobulin G

Supplementary key words phospholipid transfer protein • apolipoprotein E • enzyme-linked immunosorbent assay • high density lipoprotein metabolism

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				C. Bancells, S. Benitez, M. Jauhiainen, J. Ordonez-Llanos, P. T. Kovanen, S. Villegas, J. L. Sanchez-Quesada, and K. Oorni High binding affinity of electronegative LDL to human aortic proteoglycans depends on its aggregation level J. Lipid Res., March 1, 2009; 50(3): 446 - 455. [Abstract] [Full Text] [PDF]

				S. Nakanishi, R. Vikstedt, S. Soderlund, M. Lee-Rueckert, A. Hiukka, C. Ehnholm, M. Muilu, J. Metso, J. Naukkarinen, L. Palotie, et al. Serum, but not monocyte macrophage foam cells derived from low HDL-C subjects, displays reduced cholesterol efflux capacity J. Lipid Res., February 1, 2009; 50(2): 183 - 192. [Abstract] [Full Text] [PDF]

				C. Christoffersen, M. Jauhiainen, M. Moser, B. Porse, C. Ehnholm, M. Boesl, B. Dahlback, and L. B. Nielsen Effect of Apolipoprotein M on High Density Lipoprotein Metabolism and Atherosclerosis in Low Density Lipoprotein Receptor Knock-out Mice J. Biol. Chem., January 25, 2008; 283(4): 1839 - 1847. [Abstract] [Full Text] [PDF]

				R. Liu, M. R. Hojjati, C. M. Devlin, I. H. Hansen, and X.-C. Jiang Macrophage Phospholipid Transfer Protein Deficiency and ApoE Secretion: Impact on Mouse Plasma Cholesterol Levels and Atherosclerosis Arterioscler. Thromb. Vasc. Biol., January 1, 2007; 27(1): 190 - 196. [Abstract] [Full Text] [PDF]

				M. Lee-Rueckert, R. Vikstedt, J. Metso, C. Ehnholm, P. T. Kovanen, and M. Jauhiainen Absence of endogenous phospholipid transfer protein impairs ABCA1-dependent efflux of cholesterol from macrophage foam cells J. Lipid Res., August 1, 2006; 47(8): 1725 - 1732. [Abstract] [Full Text] [PDF]

				M. C. Cheung and J. J. Albers Active plasma phospholipid transfer protein is associated with apoA-I- but not apoE-containing lipoproteins J. Lipid Res., June 1, 2006; 47(6): 1315 - 1321. [Abstract] [Full Text] [PDF]

				G. M. Dallinga-Thie, A. van Tol, H. Hattori, P. C.N. Rensen, E. J.G. Sijbrands, and for the Diabetes Atorvastatin Lipid Intervention ( Plasma phospholipid transfer protein activity is decreased in type 2 diabetes during treatment with atorvastatin: a role for apolipoprotein e? Diabetes, May 1, 2006; 55(5): 1491 - 1496. [Abstract] [Full Text] [PDF]

				M. T. Janis, S. Siggins, E. Tahvanainen, R. Vikstedt, K. Silander, J. Metso, A. Aromaa, M.-R. Taskinen, V. M. Olkkonen, M. Jauhiainen, et al. Active and low-active forms of serum phospholipid transfer protein in a normal Finnish population sample J. Lipid Res., December 1, 2004; 45(12): 2303 - 2309. [Abstract] [Full Text] [PDF]