TNF and rheumatoid arthritis: No significant differences in the percentages of cytokine‐expressing Treg cells (expressing IL‐17, IFNγ, TNF, or IL‐10) were observed between RA patients and healthy controls (see Supplementary Figure 3A, available on the Arthritis & Rheumatology web site at http://onlinelibrary.wiley.com/doi/10.1002/art.39408/abstract).