Fetuin restored the suppressive effect of CNI-1493 on LPS-induced phosphorylation of p38 MAP kinase. Normally cultured (responsive cells, A), or serum-deprived (nonresponsive cells, B and C) RAW 264.7 cells were pretreated with CNI-1493 either alone (A and B) or in combination with fetuin (C) 1 hr before LPS stimulation (100 ng/ml). Thirty minutes after LPS stimulation, cells were lysed and assayed for concentration of phosphorylated p38 by Western blotting. After detection of the signal for phospho-p38 MAP kinase (P ≈ p38), the same membranes were stripped and reprobed with antibodies against the total p38 MAP kinase (supplied in the kit, total p38) to verify equal loading of different samples.