IL4 and tuberculosis: With Th2 cytokines, differences were apparent when compared to the healthy groups e.g. median levels of IL-4 were higher in BAL than serum in both sarcoidosis (ratio of BAL: serum = 5.39) and tuberculosis (ratio = 2.01) but this pattern was reversed in healthy volunteers where almost no IL-4 was measured in the BAL giving a ratio of less than 1 (Figures 4b-d).