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Bicarbonate and functional CFTR channel are required for proper mucin secretion and link cystic fibrosis with its mucus phenotype.

ABSTRACT: Cystic fibrosis (CF) is caused by a nonfunctional chloride and bicarbonate ion channel (CF transmembrane regulator [CFTR]), but the link to the phenomenon of stagnant mucus is not well understood. Mice lacking functional CFTR (Cftr?508) have no lung phenotype but show similar ileal problems to humans. We show that the ileal mucosa in CF have a mucus that adhered to the epithelium, was denser, and was less penetrable than that of wild-type mice. The properties of the ileal mucus of CF mice were normalized by secretion into a high concentration sodium bicarbonate buffer (~100 mM). In addition, bicarbonate added to already formed CF mucus almost completely restored the mucus properties. This knowledge may provide novel therapeutic options for CF.

SUBMITTER: Gustafsson JK

PROVIDER: S-EPMC3405509 | biostudies-literature | 2012 Jul

REPOSITORIES: biostudies-literature

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Bicarbonate and functional CFTR channel are required for proper mucin secretion and link cystic fibrosis with its mucus phenotype.

Gustafsson Jenny K JK Ermund Anna A Ambort Daniel D Johansson Malin E V ME Nilsson Harriet E HE Thorell Kaisa K Hebert Hans H Sjövall Henrik H Hansson Gunnar C GC

The Journal of experimental medicine 20120618 7

Cystic fibrosis (CF) is caused by a nonfunctional chloride and bicarbonate ion channel (CF transmembrane regulator [CFTR]), but the link to the phenomenon of stagnant mucus is not well understood. Mice lacking functional CFTR (CftrΔ508) have no lung phenotype but show similar ileal problems to humans. We show that the ileal mucosa in CF have a mucus that adhered to the epithelium, was denser, and was less penetrable than that of wild-type mice. The properties of the ileal mucus of CF mice were n ...[more]

PMID: 22711878

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