IL-7 is a Key Driver Cytokine in Spondyloarthritis?

Figure 3

(a) The TGF-β receptor phosphorylates Smad2/3. Phosphorylated, they bind to Smad4, and the resulting complex translocates to the nucleus and activates transcription through binding to the CAGA sequence, i.e., initiates signal transduction. (b) Smad7 inhibits Smad2/3 TGF-β-mediated phosphorylation and competes with the Smad2/3 binding to the TGF-β receptor. In turn, TGF-β then induces the production of both IL-7 (b) and Smad7, and this in turn is also stimulated by IL-7, ratifying a negative feedback loop of control of TGF-β.

(a)

(b)