Effect of taurine on apoB secretion into the medium. HepG2 cells were cultured in the DMEM with (10-4 or 10-3 M) or without taurine for 24 hr. The apoB concentration in the medium was measured by using a sandwich enzyme-linked immunosorbent assay. Values are expressed as mean ± SE (n = 4). a, b Different letters show significant differences at P < 0.05.