Effects of purified tocopherols on FBGC formation. a: Dose dependency of α-tocopherol. b: Comparison of tocopherols. The indicated concentrations of purified α-tocopherol (circles), β-tocopherol (squares), γ-tocopherol (triangles), or δ-tocopherol (diamonds) were added to day 3 macrophages, and the cultures were fixed and stained with May-Grünwald/Giemsa on day 7. Results are expressed as percent FBGC formation ± SEM, n = 3 monocyte donors that are different for a and b.