RESUMO
Genetic deficiency of ectodysplasin A (EDA) causes X-linked hypohidrotic ectodermal dysplasia, a congenital condition characterized by the absence or abnormal formation of sweat glands, teeth, and several skin appendages. Stimulation of the EDA receptor (EDAR) with agonists in the form of recombinant EDA or anti-EDAR antibodies can compensate for the absence of Eda in a mouse model of Eda deficiency, provided that agonists are administered in a timely manner during fetal development. Here we provide detailed protocols for the administration of EDAR agonists or antagonists, or other proteins, by the intravenous, intraperitoneal, and intra-amniotic routes as well as protocols to collect blood, to visualize sweat gland function, and to prepare skulls in mice.
Assuntos
Receptor Edar/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Vias de Administração de Medicamentos , Displasia Ectodérmica/tratamento farmacológico , Displasia Ectodérmica/genética , Displasia Ectodérmica/metabolismo , Receptor Edar/genética , Camundongos , Fenótipo , Proteínas Recombinantes/administração & dosagem , Resultado do TratamentoRESUMO
Hypohidrotic ectodermal dysplasias (HED) are hereditary differentiation disorders of multiple ectodermal structures including the mammary gland. The X-linked form of HED (XLHED) is caused by a lack of the secreted signaling molecule ectodysplasin A1 (EDA1) which is encoded by the gene EDA and belongs to the tumor necrosis factor (TNF) superfamily. Although male patients (hemizygous) are usually more severely affected by XLHED, heterozygous female carriers of an EDA mutation may also suffer from a variety of symptoms, in particular from abnormal development of their breasts. In Tabby mice, a well-studied animal model of XLHED, EDA1 is absent. We investigated the effects of prenatal administration of Fc-EDA, a recombinant EDA1 replacement protein, on mammary gland development in female Tabby mice. Intra-amniotic delivery of Fc-EDA to fetal animals resulted later in improved breastfeeding and thus promoted the growth of their offspring. In detail, such treatment led to a normalization of the nipple shape (protrusion, tapering) that facilitated sucking. Mammary glands of treated female Tabby mice also showed internal changes, including enhanced branching morphogenesis and ductal elongation. Our findings indicate that EDA receptor stimulation during development has a stable impact on later stages of mammary gland differentiation, including lactation, but also show that intra-amniotic administration of an EDA1 replacement protein to fetal Tabby mice partially corrects the mammary gland phenotype in female adult animals.
Assuntos
Displasia Ectodérmica Anidrótica Tipo 1/terapia , Glândulas Mamárias Animais/patologia , Animais , Mama/patologia , Aleitamento Materno/métodos , Diferenciação Celular/fisiologia , Modelos Animais de Doenças , Ectodisplasinas/genética , Feminino , Terapias Fetais/métodos , Fragmentos Fc das Imunoglobulinas/genética , Lactação/genética , Camundongos , Camundongos Endogâmicos C57BL , Morfogênese/genética , Morfogênese/fisiologia , Mutação/genética , Gravidez , Proteínas Recombinantes de Fusão/genética , Transdução de Sinais/genética , Transdução de Sinais/fisiologiaRESUMO
Genetic deficiency of ectodysplasin A (EDA) causes X-linked hypohidrotic ectodermal dysplasia (XLHED), in which the development of sweat glands is irreversibly impaired, an condition that can lead to life-threatening hyperthermia. We observed normal development of mouse fetuses with Eda mutations after they had been exposed in utero to a recombinant protein that includes the receptor-binding domain of EDA. We administered this protein intraamniotically to two affected human twins at gestational weeks 26 and 31 and to a single affected human fetus at gestational week 26; the infants, born in week 33 (twins) and week 39 (singleton), were able to sweat normally, and XLHED-related illness had not developed by 14 to 22 months of age. (Funded by Edimer Pharmaceuticals and others.).