IL17A and infection: We then repeated this experiment in IFN-γ-/- mice (Fig 4D). When lesions started to appear (week 2.5), digoxin and SR1001 were injected i.p. Although we didn’t observe a major effect on footpad swelling, such treatments significantly blocked the development of secondary lesions in the tail (Fig 4E) and decreased IL-17A secretion in the popliteal nodes at 4 weeks post infection (Fig 4F), and in the popliteal and iliac lymph nodes 7 weeks post infection (Fig 4G–4H).