Sarcoidosis and Immune Cells in Lung, Lymph Nodes and Blood

Background: Sarcoidosis is an inflammatory disease, most commonly affecting the lungs and intrathoracic lymph nodes but can affect virtually any organ, sometimes manifesting as life threatening cardiac arrythmias. Some patients resolve spontaneously, whereas others get a chronic disease leading to for instance impaired lung function and cardiac failure. The most severe cases might need a transplantation. In the lungs, activated T cells are accumulated leading to release of cytokines, especially TNF-alpha is regarded as crucial for disease progression. Some segments of the T cell receptor and specific genes (HLA types) are connected to a resolving disease. More detailed knowledge about mechanisms why some experience a chronic disease course and others resolve spontaneously without treatment is to a large extent lacking. There is no cure, and despite treatment with immunosuppressants (of