Effects of CSD and its subdomains on pSmad 2/3 expression in normal, TGFβ-treated, and SSc monocytes. As described in the Methods, monocytes were isolated, plated on coverslips, treated with the indicated reagents (TGFβ, CSD, or its subdomains), fixed, and stained for pSmad 2/3 and with the nuclear stain DAPI. Representative images are shown selected from 20 to 60 cells observed from four donors in each category. (A) Normal monocytes treated with TGFβ and CSD; (B) SSc monocytes treated with CSD and its subdomains; (C) Normal monocytes treated with TGFβ and CSD subdomains. The Antennapedia Internalization Sequence alone was routinely used as the Control peptide; when tested scrambled CSD attached to the Antennapedia Internalization Sequence gave similar results.