Intracellular lipid content. Lipid content of cells after 16 h lipoprotein pre-treatment and 4 h conditioning with or without exogenous TNF-α (1 ng/ml). (A) Intracellular levels of total cholesterol (free cholesterol and cholesterol ester) normalized to cell protein, (B) intracellular triglyceride levels normalized to cell protein. Data represent mean ± SEM of cells from six different blood donors. * = P < 0.05, ** = P < 0.01 and *** = P < 0.001 for comparisons of intracellular lipid content of lipoprotein treated vs. non-treated cells. Light grey = non-stimulated cells, dark grey = cells stimulated by incubation with TNF-α.