Bone marrow (BM) macrophages from transgenic (Tg) mice were stimulated to produce tumor necrosis factor-alpha (TNFα) upon stimulation with lipopolysaccharide (LPS). Temporal changes in the level of TNFα mRNA expressed by BM macrophages were measured upon stimulation with LPS. TNFα mRNA level peaked at 3 hours and gradually decreased and was significantly higher in Tg mice than in wild-type (Wt) mice over time (a). The amount of TNFα in culture media was measured after 24 hours of LPS stimulation by using a specific enzyme-linked immunosorbent assay (b). LPS stimulated secretion of TNFα from BM macrophages in a dose-dependent manner, and levels were higher in Tg mice than in Wt mice (*P < 0.05). The values are expressed as the mean ± standard deviation for three different mice. GAPDH, glyceraldhyde-3-phosphate dehydrogenase.