TNFRSF18 and rheumatoid arthritis: Intriguingly, since GITR is a CS-inducible molecule, it would be of great interest to clarify whether the increase of CD25−FoxP3+ cells that de Paz et al. observed in CS-treated RA patients [75, 76] was due to a selective increase of CD25−FoxP3+GITR+ rather than CD25−FoxP3+GITR− T lymphocytes.