A homozygous frameshift mutation in the mouse Flg gene facilitates enhanced percutaneous allergen priming.
Loss-of-function mutations in the FLG (filaggrin) gene cause the semidominant keratinizing disorder ichthyosis vulgaris and convey major genetic risk for atopic dermatitis (eczema), eczema-associated asthma and other allergic phenotypes. Several low-frequency FLG null alleles occur in Europeans and Asians, with a cumulative frequency of approximately 9% in Europe. Here we report a 1-bp deletion mutation, 5303delA, analogous to common human FLG mutations, within the murine Flg gene in the spontaneous mouse mutant flaky tail (ft). We demonstrate that topical application of allergen to mice homozygous for this mutation results in cutaneous inflammatory infiltrates and enhanced cutaneous allergen priming with development of allergen-specific antibody responses. These data validate flaky tail as a useful model of filaggrin deficiency and provide experimental evidence for the hypothesis that antigen transfer through a defective epidermal barrier is a key mechanism underlying elevated IgE sensitization and initiation of cutaneous inflammation in humans with filaggrin-related atopic disease.
Fallon
Padraic G
PG
Institute of Molecular Medicine, Trinity College Dublin, Ireland.
Sasaki
Takashi
T
Sandilands
Aileen
A
Campbell
Linda E
LE
Saunders
Sean P
SP
Mangan
Niamh E
NE
Callanan
John J
JJ
Kawasaki
Hiroshi
H
Shiohama
Aiko
A
Kubo
Akiharu
A
Sundberg
John P
JP
Presland
Richard B
RB
Fleckman
Philip
P
Shimizu
Nobuyoshi
N
Kudoh
Jun
J
Irvine
Alan D
AD
Amagai
Masayuki
M
McLean
W H Irwin
WH
D000485:Allergens / Q000276:immunology; D000818:Animals; D001483:Base Sequence; D003876:Dermatitis, Atopic / Q000235:genetics* / Q000276:immunology; D005260:Female; D000091344:Filaggrin Proteins; D016368:Frameshift Mutation / Q000235:genetics*; D005838:Genotype; D006720:Homozygote; D006967:Hypersensitivity / Q000235:genetics / Q000276:immunology; D016112:Ichthyosis Vulgaris / Q000235:genetics / Q000276:immunology; D007073:Immunoglobulin E / Q000276:immunology; D007381:Intermediate Filament Proteins / Q000235:genetics*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D008957:Models, Genetic; D008969:Molecular Sequence Data
D000485:Allergens; C000717249:FLG protein, human; D000091344:Filaggrin Proteins; D007381:Intermediate Filament Proteins; D007073:Immunoglobulin E