RESUMEN
The aim of this article is to provide methods for the isolation and identification of pancreatic stem cells and cell source for research and therapy of diabetes. ICCs were isolated by collagenase IV digesting and then cultured; epithelial cells were purified from monolayer cultured ICCs. The growth curve of the epithelial cells was measured by MTT. The expression of molecular markers in the cells was identified by immunohistochemical staining. The surface markers in the epithelial cells were analyzed by FACS. Epithelial cells were purified from isolated human fetal ICCs and passaged 40 times, and 10(6) - 10(8) cells were cryopreservated per passage. The growth curve demonstrated that the epithelial cells proliferated rapidly. The epithelial cells expressed PDX-1, PCNA, CK-7, CK-19, Nestin, Glut2, and Vimentin, but Insulin was undetected. The cells expressed CD29, CD44, and CD166, but did not express CD11a, CD14, CD34, CD45, CD90, CD105, and CD117. Taken together, these results indicate that self-renewable epithelial cells can be isolated and purified from human fetal pancreas. These also show that the epithelial cells originate from ducts and have the characteristics of pancreatic stem cells.
Asunto(s)
Humanos , Técnicas de Cultivo de Célula , Proliferación Celular , Separación Celular , Supervivencia Celular , Células Cultivadas , Células Epiteliales , Biología Celular , Metabolismo , Feto , Citometría de Flujo , Proteínas de Homeodominio , Receptores de Hialuranos , Inmunohistoquímica , Integrina beta1 , Islotes Pancreáticos , Antígeno Nuclear de Célula en Proliferación , Células Madre , Biología Celular , Metabolismo , TransactivadoresRESUMEN
Retinoic acid plays an important role in maintaining the structure and function in male testis. Recent studies showed that there is a group of genes that can be specially activated by retinoic acid during the development of male reproductive gland. The gene Stra 8 (Stimulated by Retinoic Acid) was one of the gene in this group. In mouse, Stra 8 is restrictively expressed in male germ line cells, and its function is related to the development of sperm. In order to investigate the feature of Stra 8 gene expression,the 1.4 kb (-1407 - +7) promoter region of Stra 8 gene was amplified from mouse genomic DNA. The DNA fragment was then cloned into a promoter less vector to form the construct that contained the 1.4 kb promoter region, and the reporter gene of EGFP that was regulated by 1.4kb Stra 8 promoter. To investigate the specificity of Stra 8 promoter,the vector pStro-EGFP was transfected into undifferentiated mouse stem cells such as ES-129, bone marrow mesenchymal stem cell (mMSC) and spermatogonial stem cell (mSSC). The results showed that the expression of GFP was only observed in the mSSC cells,which indicated that Stra 8 gene was specially regulated in testis tissue. As the gene marker,vector pStra8-EGFP was then transfected to undifferentiated mMSC cells. After being selected by G418 for 2 weeks,the mMSC cells were induced by retinoic acid. After 12 hours induction, some induced cells started to express GFP protein, which was observed under the fluorescence microscope. At the same time, several stem cell specificity biomarkers such as Oct4, and spermatogonial stem cell biomarkers such as CyclinA2 and Stra 8 were detected in the induced cells by RT-PCR method. These results showed that the mMSCs would differentiated to spermatognial stem cells after induced by Retinoic Acid.
Asunto(s)
Animales , Masculino , Ratones , Proteínas Adaptadoras Transductoras de Señales , Diferenciación Celular , Genética , Células Cultivadas , Expresión Génica , Regiones Promotoras Genéticas , Proteínas , Genética , Espermatogonias , Biología Celular , Metabolismo , Células Madre , Biología Celular , Metabolismo , Tretinoina , FarmacologíaRESUMEN
Male germ stem cells (mGSCs), which is in testis after sex differentiation, derive from primordial germ cells. In this study, bovine mGSCs were isolated from testis of 20 weeks fetuses. Number of CD9 positive cells of the cells through two-steps adhering plates velocity different was 95.8% by flow cytometer. The carina-type cells clones and the plane-type cells clones appeared in co-cultured system. One cells lines had been successively maintained for 4 passages, and the cells clusters showed AKP positive staining. The cells clusters showed nest-shape in third passage showed SSEA1 and Oct-4 positive staining. These cells can also spontaneously differentiate into c-kit positive staining germ cells, and the cells were directional induced to formaactin positive staining cardiac-like cells cluster and NF positive staining neuron-like cells. The conclusion showed that male germ stem cells from 20 weeks bovine fetuses could be in vitro formed like embryonic stem cells.
Asunto(s)
Animales , Bovinos , Masculino , Diferenciación Celular , Fisiología , Células Cultivadas , Células Madre Embrionarias , Biología Celular , Feto , Biología Celular , Células Madre Pluripotentes , Biología Celular , Espermatozoides , Biología CelularRESUMEN
Adipose-tissue mesenchymal stem cells, is one kind of multipotent stem cells, can differentiate into adipogenic, osteogenic, chondrogenic, myogenic cells and so on in vitro and in vivo. Human adipose tissue is plentiful, easily harvested in large quantity with little patient discomfort. Adipose-tissue derived mesenchymal stem cells may be an alternative stem cell source for mesenchymal tissue regeneration and engineering without ethical consideration of embryonic stem cells and severe pain resulted by bone marrow procurement. The research work on adipose-tissue mesenchymal stem cells and future clinical perspectives were reviewed.