Background: Cytokine polymorphisms are inconsistently associated with transplant rejection and other adverse outcomes. To address this controversy, we evaluated cytokine single nucleotide polymorphisms (SNPs) in a lung transplant cohort.
Methods: All patients who underwent lung transplantation from 1993 to 1998 and had post-transplant survival of at least 6 months were included in the initial analysis. Subjects were genotyped for: TNF-alpha -308 G/A; IFN-gamma +874 A/T; TGF-beta1 +869 T/C and +915 G/C; IL-10 -1082 A/G, -819 C/T and -592 C/A; and IL-6 -174 G/C. End-points were onset of broncholitis obliterans syndrome (BOS) and survival.
Results: In the cohort, 78 subjects, with an overall mean +/- SE survival 2,339 +/- 117 days, had no correlation between onset of BOS1, BOS2 or survival with TNF-alpha, IFN-gamma, TGF-beta1 or IL-10 gene polymorphisms. However, IL-6 polymorphisms GG or GC were associated with an earlier onset of BOS1 (p = 0.039), BOS2 (p = 0.021), and decreased overall post-transplant survival (p = 0.038). A second cohort of more recent lung transplant recipients did not validate an association between IL-6 polymorphisms and earlier onset of BOS1 (p = 0.70), BOS2 (p = 0.54) or overall post-transplant survival (p = 0.25).
Conclusions: Polymorphisms of TNF-alpha, IFN-gamma, TGF-beta1, IL-10 and IL-6 do not appear to influence the onset of BOS or graft survival in recipients.