Increased production of IFN-γ and perforin by CD4+CD28− T cells has been shown not only in RA but also in AS [9, 17], polymyalgia rheumatica/giant cell arteritis [15, 19], granulomatous polyangiitis [21], and abdominal aortic aneurysms [27]. The gene discussed is CD4; the disease is rheumatoid arthritis.