Figure 2.

SAR439459 binds to various TGFβ isoforms and inhibits TGFβ-mediated signaling similar to fresolimumab. SPR Biacore data shows similar binding properties of SAR439459 and fresolimumab against human TGFβ1, 2, and 3 proteins, (a). Murine colon carcinoma, MC38; mouse breast cancer cells, EMT6 and human colorectal carcinoma cells HCT116-overexpressing TGFβRII were cultured with human TGFβ1 (1 ng/mL) in presence of SAR439459, fresolimumab or isotype control. Total and phosphorylated SMAD2/3 protein levels were assessed by ELISA. Graph shows ratio of phospho-/total SMAD2/3 for SAR439459 and fresolimumab and isotype control, (b). P value <.0001 using two-way ANOVA test. SBE reporter cells were cultured in the presence of human TGFβ isoforms −1, −2, and −3 with various concentrations of SAR439459, fresolimumab or isotype control and luminescence activity was measured. Graphs show ability of SAR439459 and fresolimumab to prevent TGFβ1, 2 and 3-mediated SMAD activation in the reporter cell line, (c). IC₅₀ values for SAR439459 were 0.008, 1.22, 0.45, and for fresolimumab were 0.02, 1.86, 0.61 nM for TGFβ1, TGFβ2, and TGFβ3 respectively. Each graph shows mean ± SEM and represents one of three independent experiments.