In RA (25, 26), type 1 diabetes (T1D) (27), multiple sclerosis (MS) (28), Graves’ disease (GD) (29), and granulomatosis with polyangiitis (30), CD4+CD28- T cells are capable of infiltrating inflamed tissues and exacerbating immune-mediated damage. The gene discussed is CD4; the disease is rheumatoid arthritis.