In this report we provided evidence that cytokine TL1A and its receptor DR3 are expressed on pulmonary T cells and alveolar macrophages of patients with sarcoidosis, showing their highest expression in lung cells obtained from patients with the active form of the disease, and when localized around and inside the granuloma or, in general terms, at the sites of disease activity. The gene discussed is TNFRSF25; the disease is sarcoidosis.