Early studies demonstrate that lung T lymphocytes from patients with active pulmonary sarcoidosis spontaneously release interleukin (IL)-2 (15) and interferon (IFN)-γ (16), and both lung and blood T lymphocytes in individuals with active pulmonary sarcoidosis spontaneously express functional IL-2 receptors (IL-2R) (17, 18). Here, IL2RA is linked to pulmonary sarcoidosis.