Proliferative effect of high density lipoprotein (HDL) and HDL fractions (HDL 1,2, HDL 3) on virus transformed lymphoblastoid cells

Abstract

The growth-promoting activities of plasma lipoproteins (LDL, HDL, HDL 1,2, HDL 3) and total HDL apolipoproteins on a virus transformed lymphoblastoid cell line in vitro, has been compared. When maintained in lipoprotein-deficient serum-supplemented medium, these cells do not proliferate optimally. The addition of either HDL, HDL 1,2 or HDL 3 induced optimal cell proliferation as compared to the result observed in fetal calf serum-supplemented medium. The HDL 1,2 subfraction was found to be more potent than the HDL 3 subfraction in supporting cell growth. Total HDL apolipoproteins were able to support significant cell proliferation. In contrast, LDL did not promote cell growth. In serum-free conditions and in the presence of transferrin, only HDL and HDL subfractions induced cell proliferation. These results suggest that HDL and HDL subfractions could initiate B lymphoblastoid cell growth and that total HDL apolipoproteins could support a part of cell proliferation.