FIG. 3.
Molecular activity of LF-EDIN chimera. (A) HUVEC monolayers were intoxicated with LET (3 μg/ml PA plus 1 μg/ml LF1-254-EDIN) or LETm (3 μg/ml LETR185E-PA plus 1 μg/ml LF1-254-EDINR185E) for the indicated periods of time. Immunoblots of anti-MEK2N20, anti-actin, anti-phosphorylated-ERK1/2 (p-ERK1/2), and anti-ERK1/2 show the absence of activity of LET with ERK1/2. (B) Absence of activation of caspase-3 by LET. HUVEC monolayers were intoxicated for 8 h with LET (3 μg/ml PA plus 1 μg/ml LF1-254-EDIN). Staurosporin 1 μM (Stauro) was added as a positive control. The activities are expressed in arbitrary units (A.U.) per mg of proteins (means ± standard deviations of two experiments performed in triplicate).