Figure 1

TNF leads to activation of MAPK in arthritic joints of hTNFtg mice. Pooled protein extracts from three normal wild-type mice (left lanes) as well as three arthritic human tumour necrosis factor transgenic (hTNFtg) mice (right lanes) aged 10 weeks were analyzed for the phosphorylated forms of (a) p38 mitogen-activated protein kinase (MAPK)α, (c) extracellular signal regulated kinase (ERK), and (e) c-Jun amino-terminal kinase (JNK) by immunoblotting. In addition, total (b) p38MAPKα, (d) ERK and (f) JNK, as well as (g) actin, were analyzed.