Distinct roles of FOXA2 and FOXA3 in allergic airway disease and asthma.
BACKGROUND
Increased production of mucus is a prominent feature of asthma. IL-13-driven mucous cell metaplasia is associated with decreased expression of the transcription factor FOXA2 and increased expression of the related transcription factor FOXA3 in animal and cell culture models.


OBJECTIVE
Establish how changes in FOXA2 and FOXA3 expression contribute to mucous metaplasia and determine whether FOXA2 and FOXA3 expression is altered in asthma.


METHODS
Mice expressing a Foxa2 transgene in airway epithelial cells and mice deficient in Foxa3 were analyzed after allergen sensitization and challenge. Expression of FOXA2, FOXA3, MUC5AC, and the highly IL-13-inducible gene CLCA1 was analyzed in airway biopsies from subjects with asthma and control subjects.


RESULTS
Expression of a Foxa2 transgene reduced allergen-induced mucous metaplasia by 45% compared with control transgenic mice (P < 0.05) whereas inactivation of Foxa3 had no detectable effects on mucous metaplasia. Expression of FOXA2 was reduced in subjects with asthma and was negatively correlated with MUC5AC and CLCA1 levels in subjects with asthma. In contrast, FOXA3 expression was not significantly correlated with MUC5AC and was positively correlated with CLCA1.


CONCLUSIONS
Increasing Foxa2 expression reduced mucous metaplasia in an allergic mouse model. Subjects with asthma had decreased FOXA2 expression, suggesting that therapeutic approaches that increase FOXA2 expression or function could be beneficial for reducing mucus production in asthma. Unlike FOXA2, FOXA3 did not regulate mucous metaplasia.
Park
Sung-Woo
SW
Lung Biology Center, University of California San Francisco, San Francisco, California 94143, USA.
Verhaeghe
Catherine
C
Nguyenvu
Louis T
LT
Barbeau
Rebecca
R
Eisley
Christopher J
CJ
Nakagami
Yasuhiro
Y
Huang
Xiaozhu
X
Woodruff
Prescott G
PG
Fahy
John V
JV
Erle
David J
DJ
D000818:Animals; D001249:Asthma / Q000235:genetics / Q000276:immunology / Q000473:pathology; D004195:Disease Models, Animal; D004847:Epithelial Cells / Q000276:immunology / Q000473:pathology; D015870:Gene Expression; D051542:Hepatocyte Nuclear Factor 3-beta / Q000276:immunology / Q000378:metabolism*; D051543:Hepatocyte Nuclear Factor 3-gamma / Q000276:immunology / Q000378:metabolism*; D008168:Lung / Q000166:cytology / Q000276:immunology; D051379:Mice; D008822:Mice, Transgenic; D009093:Mucus / Q000276:immunology; D012130:Respiratory Hypersensitivity / Q000235:genetics* / Q000276:immunology / Q000473:pathology; D020133:Reverse Transcriptase Polymerase Chain Reaction
C496503:Foxa2 protein, mouse; C496506:Foxa3 protein, mouse; D051543:Hepatocyte Nuclear Factor 3-gamma; D051542:Hepatocyte Nuclear Factor 3-beta