Fig. 1.
Inhibition of NF-κB activation by MTX
(A–D) Jurkat (JKT) cells containing an NF-κB-luciferase reporter were cultured with 0.1 μM MTX for 48 h and stimulated with (A) PMA (50 nM) and ionomycin (1 μM) 6 h or (A–D) TNF-α (5 ng) 24 h prior to luciferase measurements. (B) MTX-treated JKT cells were cultured with or without BH4, N-acetyl-l-cysteine (NAC) or JNK inhibitors BI-78D3 or L-JNKi1. JNK1-DN, JNK2-DN, p53-DN or empty vector plasmids with a green fluorescent protein (GFP) plasmid were transiently transfected into JKT cells. (C and D) MTX-treated JKT cells were treated with (C) folic or folinic acid or (D) adenosine receptor antagonists caffeine and/or theophylline. Values are mean (s.d.). (A) *P < 0.05 vs PMA/ionomycin- or TNF-α-treated cultures. (B–D) *P < 0.05 vs cultures stimulated with MTX alone. Iono: ionomycin; PMA: phorbol 12-myristate 13-acetate; Theo: theophylline; NF-κB: nuclear factor κB; JNK: Jun-N-terminal kinase.