CCR6 and ulcerative colitis: However, as the described 90-fold induction of CCL20 protein levels in the BAL of CF patients compared to healthy volunteers nearly doubled a 47-fold upregulation of CCL20 mRNA expression in the gut of patients suffering from ulcerative colitis, (15, 80) this indicates a particular relevance of the CCL20 - CCR6 axis for lung homing in CF.