CD4 and Löfgren’s syndrome: Further, an expansion in BALF of CD4+ T-cells expressing T-cell receptor (TCR) Vα2.3 gene segment has been identified in HLA-DRB1*03+ sarcoidosis patients, usually with Löfgren’s syndrome (LS) i.e. with an acute disease onset with bilateral ankle arthritis and/or erythema nodosum (EN), bilateral hilar lymphadenopathy (BHL), sometimes combined with parenchymal infiltrates and usually fever [2].