Transforming Growth Factor β1 Genotypes in Relation to TGFβ1, Interleukin-8, and Tumor Necrosis Factor Alpha in Induced Sputum and Blood in Cystic Fibrosis

Background. High-producer TGF beta 1 genotypes are associated with severe lung disease in cystic fibrosis (CF), but studies combining IL-8, TNF alpha-, and TGF beta 1(+genotype) levels and their impact on CF lung disease are scarce. Aim. Assessing the relationship between TGF beta 1, IL-8, and TNF-alpha and lung disease in CF in an exacerbation-free interval. Methods. Twenty four patients delta F508 homozygous (median age 20.5 y, Shwachman score 75, FEV1(%) 83) and 8 controls (median age 27.5 y) were examined. TGF beta 1 was assessed in serum and induced sputum (IS) by ELISA, for IL-8 and TNF-alpha by chemiluminescence in IS and whole blood. Genotyping was performed for TGF beta 1 C-509T and T+869C utilizing RFLP. Results. TGF beta 1 in IS (CF/controls median 76.5/59.1 pg/mL, P < 0.074) was higher in CF. There was a negative correlation between TGF beta 1 in serum and lung function (LF) (FEV1 (r = -0.488, P = 0.025), MEF 25 (r = -0.425, P = 0.055), and VC (r = -0.572, P = 0.007)). Genotypes had no impact on TGF beta 1 in IS, serum, and LF. In IS TGF beta 1 correlated with IL-8 (r = 0.593, P < 0.007) and TNF-alpha (r = 0.536, P < 0.018) in patients colonized by bacteria with flagellin. Conclusion. TGF beta 1 in serum not in IS correlates with LF. In patients colonized by bacteria with flagellin, TGF beta 1 correlates with IL-8 and TNF-alpha in IS.