Serum soluble interleukin-2 receptor (sIL2R) and serum Krebs von den Lungen-6 (KL6) values are correlated with the number of total cells, lymphocytes and T-lymphocytes bearing CD4 in BALF, suggesting that these may reflect alveolitis induced by sarcoidosis [2]. This evidence concerns the gene CD4 and sarcoidosis.