Journal: Proceedings of the National Academy of Sciences of the United States of America
Article Title: ADAM9 enhances Th17 cell differentiation and autoimmunity by activating TGF-β1
doi: 10.1073/pnas.2023230118
Figure Lengend Snippet: Transcriptional factor ICER promotes ADAM9 expression in Th17 cells. (A and B) ICER/CREM-deficient or -sufficient naïve CD4+ T cells cultured under Th17-polarizing conditions for 3 d. (A) Relative ADAM9 mRNA expressions were assessed by qRT-PCR. Cumulative data are shown (mean ± SEM, n = 12). (B) Pro-ADAM9, ADAM9 (active), and β-actin expressions on day 3 were determined by Western blotting. A representative (of six) blot is shown (Left) and cumulative densitometric readings of ADAM9 (active) and β-actin are shown (Right) (mean ± SEM, n = 6). (C) Naïve CD4+ T cells from ICER/CREM-deficient or -sufficient IL-17GFP mice were polarized under Th17 conditions for 3 d. ADAM9 mRNA expression of FACS-sorted GFP+ cells (IL-17A–producing cells) was assessed by qRT-PCR (mean ± SEM, n = 7). (D) Th17-polarized naive CD4+ T cells were cultured in the presence of a STAT3 inhibitor (STA21, 10 μM) or dimethyl sulfoxide (DMSO) for 3 d. Pro-ADAM9, ADAM9 (active), and β-actin expressions were determined by Western blotting. A representative (of five) blot is shown (Left) and cumulative densitometric readings of ADAM9 (active) and β-actin are shown (Right) (mean ± SEM, n = 5). (E) Naive CD4+ T cells from ICER/CREM-deficient IL-17GFP mice were cultured under Th17-polarizing conditions and empty vector (empty) or ADAM9 overexpression (ADAM9 O.E.) plasmids were transfected into cultured T cells on day 1. Representative flow plots on day 3 (Left) and cumulative data (Right) are shown (mean ± SEM, n = 5). (F–H) ICERγ binds to the ADAM9 promoter directly and increases its activity. ICER/CREM-deficient or -sufficient naïve CD4+ T cells were cultured under Th17-polarizing conditions. (F) Schematic representation of the used reporter constructs. Numbers represent the position from the transcription start site of the murine ADAM9 gene. (G) The full-length ADAM9 promoter region (full) or a version containing a mutated CRE binding site (Δ-134/-130) were transfected into Th17-polarized T cells on day 1. Cells were harvested and lysed on day 2. Cumulative results of four independent experiments are shown (mean ± SEM). (H) The FLAG-tagged ICERγ overexpression vector was transfected into ICER/CREM-deficient CD4+ T cells on day one. Cells were harvested and lysed on day 3, and binding of FLAG/ICERγ to the CRE was assessed by ChIP assay. CRE at the intron1 of the ADAM9 gene and CRE at the intron 3 of the adjacent gene (Tm2d2) were used as negative controls for ChIP enrichment. Representative blots from three experiments are shown. *P < 0.05, **P < 0.01.
Article Snippet: For signal transduction studies, STA21 (STAT3 inhibitor, Santa Cruz Biotechnology) was added to cultures on day 0.
Techniques: Expressing, Cell Culture, Quantitative RT-PCR, Western Blot, Plasmid Preparation, Over Expression, Transfection, Activity Assay, Construct, Binding Assay