Growth retardation, duodenal lesions, and aberrant ileum architecture in triple null mice lacking EGF, amphiregulin, and TGF-alpha.
OBJECTIVE
Mice lacking epidermal growth factor (EGF), transforming growth factor alpha, and amphiregulin were used to identify roles for these EGF receptor (EGF-R) ligands in gastrointestinal development and mucosal integrity.


METHODS
Gastrointestinal tract development was examined in knockout mice and correlated with expression of EGF-R protein and EGF family members throughout the gut. Crossfostering experiments addressed roles of maternal- and neonatal-derived ligands in pup growth and intestinal development. Cysteamine-induced ulceration in EGF(-/-) mice was used to examine its role in mucosal cytoprotection.


RESULTS
Neonatal mice lacking all 3 ligands were growth retarded, even when reared by wild-type dams; conversely, lack of maternal ligands transiently impaired wild-type pup growth. Triple null neonates displayed spontaneous duodenal lesions, and ileal villi were truncated and fragile with reduced cellular proliferation in the crypts. However, maturation of digestive enzymes was unaffected. Adult EGF(-/-) mice displayed more severe lesions in response to cysteamine treatment compared with wild-type counterparts, although triple null mice were not more susceptible to dextran sulfate sodium-induced colitis, suggesting a differential role for these ligands in the injury response.


CONCLUSIONS
EGF-R ligands are required for development and mucosal maintenance in mouse small intestine. Both maternal and neonatal sources of growth factors are required for optimal pup growth.
Troyer
K L
KL
Department of Microbiology & Immunology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7260, USA.
Luetteke
N C
NC
Saxon
M L
ML
Qiu
T H
TH
Xian
C J
CJ
Lee
D C
DC
D066258:Amphiregulin; D000818:Animals; D001835:Body Weight; D004378:Duodenal Diseases / Q000473:pathology*; D004386:Duodenum / Q000254:growth & development; D066255:EGF Family of Proteins; D004815:Epidermal Growth Factor / Q000172:deficiency* / Q000502:physiology; D005260:Female; D006023:Glycoproteins / Q000172:deficiency* / Q000502:physiology; D006130:Growth Disorders / Q000209:etiology* / Q000235:genetics; D006133:Growth Substances / Q000172:deficiency* / Q000502:physiology; D036341:Intercellular Signaling Peptides and Proteins; D051379:Mice; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013045:Species Specificity; D015291:Transforming Growth Factors / Q000172:deficiency* / Q000502:physiology
D066258:Amphiregulin; C587849:Areg protein, mouse; D066255:EGF Family of Proteins; D006023:Glycoproteins; D006133:Growth Substances; D036341:Intercellular Signaling Peptides and Proteins; D004815:Epidermal Growth Factor; D015291:Transforming Growth Factors