Dr. Christine Smith on Instagram: "The Th17 chronic tissue damage pathway is like a team of janitors that mean well but carry cleaning chemicals strong enough to damage the building they’re supposed to protect. These janitors are Th17 cells—a special type of CD4+ T cell—and they get called into action when the immune system thinks a mess is getting out of control. Naive CD4+ T cells start as untrained workers, and molecules like IL-6 and TGF-β act as their supervisors. They teach these cells how