Phospholipid transfer protein mediated conversion of high density lipoproteins generates pre beta 1-HDL

Biochim Biophys Acta. 1996 Jun 11;1301(3):255-62. doi: 10.1016/0005-2760(96)00050-1.


High density lipoproteins (HDL) subclasses can be differentiated by two-dimensional non-denaturing polyacrylamide gradient gel electrophoresis (2D-PAGGE) and subsequent immunoblotting. The quantitatively minor HDL-subclasses pre beta 1-LpA-I and gamma-LpE are initial acceptors of cell-derived cholesterol into the plasma compartment. In this study we analysed the effect of phospholipid transfer protein (PLTP) on the electrophoretic distribution of HDL-subclasses in plasma as well as the ability of plasma, pre beta 1-LpA-I, and gamma-LpE to take up [3H]cholesterol from labeled fibroblasts. Pre beta 1-LpA-I but not gamma-LpE disappeared during a 16 hours incubation in the absence of PLTP. During a one minute incubation pre beta 1-LpA-I of pre-incubated plasma released 75% less [3H]cholesterol from radiolabeled fibroblasts than pre beta 1-LpA-I of control plasma. Pre-incubation of plasma reduced the uptake of [3H]cholesterol by gamma-LpE by 40%. Totally, the cholesterol efflux capacity of plasma decreased by 10% compared to the original sample. The amount of immunodetectable pre beta 1-LpA-I increased when plasma was incubated in the presence of PLTP while the amount of immunodetectable gamma-LpE did not change. After one minute incubation of PLTP-conditioned plasma with [3H]cholesterol-labeled fibroblasts, the amount of radioactive cholesterol taken up by pre beta 1-LpA-I was twice as high as in control plasma whereas the amount of [3H]cholesterol taken up by gamma-LpE remained unchanged. As a net result, treatment with PLTP increased the cholesterol efflux into total plasma by 40%. Together with results of previous studies our data suggest that the conversion of alpha-LpA-I3 into alpha-LpA-I2 by PLTP generates pre beta 1-LpA-I but not gamma-LpE. PLTP helps to enhance the uptake of cell-derived cholesterol by pre beta 1-LpA-I and, thereby, the cholesterol efflux capacity of normal plasma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apolipoprotein A-I / metabolism
  • Apolipoproteins E / metabolism
  • Carrier Proteins / metabolism*
  • Cells, Cultured
  • Cholesterol / metabolism
  • Electrophoresis, Gel, Two-Dimensional
  • Fibroblasts / metabolism
  • Humans
  • Immunoblotting
  • Lipoprotein(a) / analogs & derivatives
  • Lipoprotein(a) / metabolism
  • Lipoproteins, HDL / metabolism*
  • Membrane Proteins / metabolism*
  • Phospholipid Transfer Proteins*
  • Tangier Disease / metabolism


  • Apolipoprotein A-I
  • Apolipoproteins E
  • Carrier Proteins
  • Lipoprotein(a)
  • Lipoproteins, HDL
  • Membrane Proteins
  • Phospholipid Transfer Proteins
  • lipoprotein A-I
  • Cholesterol