RESUMO
The purpose of this study was to characterize neural crest-derived cells within the adult murine iris. The iris was isolated from P0-Cre/Floxed-EGFP transgenic (TG) mice. The isolated iris cells formed EGFP-positive spheres on non-adhesive culture plates. Immunostaining showed that these EGFP-positive spheres expressed neural crest markers including Sox10 and p75NTR, and these cells showing in vitro sphere-forming ability were originally resided in the iris stroma (IS), in vivo. Real-time RT-PCR showed that the EGFP-positive spheres expressed significantly higher levels of the neural crest markers than EGFP-negative spheres and bone marrow-derived mesenchymal stem cells. Furthermore, the iris stromal sphere had capability to differentiate into various cell lineages including smooth muscle and cartilage. These data indicate that neural crest-derived multipotent cells can be isolated from the murine IS and expanded in sphere culture.
Assuntos
Células-Tronco Adultas/citologia , Iris/citologia , Células-Tronco Multipotentes/citologia , Crista Neural/citologia , Animais , Técnicas de Cultura de Células , Linhagem da Célula , Proteínas de Fluorescência Verde/genética , Células-Tronco Mesenquimais/citologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Camundongos TransgênicosRESUMO
PAX6/Pax6 gene encodes a transcription factor that is crucially required for eye development. Pax6 heterozygous mutant mouse (Pax6(Sey/+)) shows various ocular defects, especially in the anterior segment. It has been well known that the induction of the lens and development of the cornea and retina are dependent on PAX6/Pax6 in a cell-autonomous fashion, although the influence of PAX6/Pax6 on the other tissues derived from the ocular mesenchyme is largely unknown. Using transgenic mouse lines in which neural crest cells are genetically marked by LacZ or EGFP, we revealed the extensive contribution of neural crest derived cells (NCDCs) to the ocular tissues. Furthermore, various eye defects in Pax6(Sey/+) mouse were accompanied by abnormal distribution of NCDCs from early developmental stages to the adult. In Pax6(Sey/+) mouse mice, neural crest cells abnormally migrated into the developing eye in a cell nonautonomous manner at early embryonic stages. These results indicate that normal distribution and integration of NCDCs in ocular tissues depend on a proper dosage of Pax6, and that Pax6(Sey/+) eye anomalies are caused by cell autonomous and nonautonomous defects due to Pax6 haploinsufficiency.
Assuntos
Padronização Corporal/genética , Movimento Celular/genética , Modelos Animais de Doenças , Anormalidades do Olho/embriologia , Anormalidades do Olho/genética , Crista Neural/citologia , Fatores de Transcrição Box Pareados/deficiência , Animais , Desenvolvimento Embrionário/genética , Proteínas do Olho/genética , Feminino , Proteínas de Homeodomínio/genética , Homozigoto , Humanos , Integrases/metabolismo , Perda de Heterozigosidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Modelos Biológicos , Crista Neural/anormalidades , Fator de Transcrição PAX6 , Fatores de Transcrição Box Pareados/genética , Proteínas Repressoras/genéticaRESUMO
Arodent cardiac side population cell fraction formed clonal spheroids in serum-free medium, which expressed nestin, Musashi-1, and multi-drug resistance transporter gene 1, markers of undifferentiated neural precursor cells. These markers were lost following differentiation, and were replaced by the expression of neuron-, glial-, smooth muscle cell-, or cardiomyocyte-specific proteins. Cardiosphere-derived cells transplanted into chick embryos migrated to the truncus arteriosus and cardiac outflow tract and contributed to dorsal root ganglia, spinal nerves, and aortic smooth muscle cells. Lineage studies using double transgenic mice encoding protein 0-Cre/Floxed-EGFP revealed undifferentiated and differentiated neural crest-derived cells in the fetal myocardium. Undifferentiated cells expressed GATA-binding protein 4 and nestin, but not actinin, whereas the differentiated cells were identified as cardiomyocytes. These results suggest that cardiac neural crest-derived cells migrate into the heart, remain there as dormant multipotent stem cells-and under the right conditions-differentiate into cardiomyocytes and typical neural crest-derived cells, including neurons, glia, and smooth muscle.
