Tacrolimus and MPA can inhibit signaling pathway activation in whole-blood samples.

<p>(A) Phospho-p38MAPK (upper left panel), p-ERK (upper right panel) and p-Akt (lower panel) phosphorylation in monocytes was measured as MFI level. Blood samples from healthy volunteers were spiked with vehicle, 10 ng/ml tacrolimus, 50 ng/ml tacrolimus, 200 ng/ml tacrolimus, 10 μg/ml MPA or 20 μM of the MAPK inhibitor SB203580. The effect of tacrolimus and MPA was based on the stimulated samples without the addition of drugs. The MAPK inhibitor was used as a positive control. Gating was performed according to <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0170806#pone.0170806.g002" target="_blank">Fig 2</a>. Tacrolimus was found to have an effect on p38MAPK, ERK and Akt phosphorylation. Akt and ERK phosphorylation was decreased in the presence of MPA. (B) Percentages of inhibition for the phosphorylation of p38MAPK (upper left panel), ERK (upper right panel) and Akt (lower panel). Data are normalized for the MFI values of the stimulated samples without the addition of immunosuppressive drugs. (Data are plotted as the mean ±SEM; n = 5) *) p < 0.05; **) p < 0.01; ***) p < 0.001.</p>