Four embryonic stem (ES) cell lines, designated CE1, CE2, CE3 and CE4, were isolated from C57BL/6J blastocysts. The ratio of normal diploid composition of these cell lines is above 70%. To examine the differentiation...Four embryonic stem (ES) cell lines, designated CE1, CE2, CE3 and CE4, were isolated from C57BL/6J blastocysts. The ratio of normal diploid composition of these cell lines is above 70%. To examine the differentiation potential of the ES cells, the CE2 cells were injected subcutaneously into syngenic mice, and many kinds of differentiated cells were observed on the sections of the teratoma derived from this ES cell line. On the other hand, to test the chimeric ability of the ES cells, the CE2 cells were microinjected into the blastocysts of ICR mice, and a chimera was obtained among living pups. These results show that CE2 ES cells are pluripotent stem cells, which can differentiate into many kinds of cell types, and can be used as a cell system for further research.展开更多
In the field of developmental biology and regenerative medicine,mammalian interspecific chimeras have been proved very useful for investigating early embryonic development and the immune system establishment,and exten...In the field of developmental biology and regenerative medicine,mammalian interspecific chimeras have been proved very useful for investigating early embryonic development and the immune system establishment,and extended to a promising potential for human organ generation(Rossant et al.,1982).展开更多
Objective To find out a proper way to detect green fluorescent protein (GFP). Methods Kidneys, livers and femurs from GFP transgenic mice and C57BL/6J wild type mice were employed for in vivo study. The samples were d...Objective To find out a proper way to detect green fluorescent protein (GFP). Methods Kidneys, livers and femurs from GFP transgenic mice and C57BL/6J wild type mice were employed for in vivo study. The samples were dehydrated with alcohol and acetone individually before embedding, then frozen, paraffin and resin sections were made for the detection of GFP. C3 P12 cells which derived from calvaria bone cells of GFP transgenic mouse were used for the detection of GFP in vitro. Cells were exposed to alcohol, acetone and PBS after paraformaldehyde fixation. Laser scanning microscopy was employed for GFP detection. Results In frozen sections, both kidney and liver samples which exposed to 4% buffered paraformaldehyde fixation had strong GFP signals, while GFP signal disappeared completely in fresh frozen sections without fixation. Much stronger GFP intensity was found in acetone treated samples than in alcohol treated paraffin sections, but without apparent difference in GFP intensity in acetone and alcohol treated resin samples. Acetone and alcohol made no difference in fixed C3 cells in different time courses. Conclusion Acetone treated paraffin sections are preferable for GFP detection.展开更多
文摘Four embryonic stem (ES) cell lines, designated CE1, CE2, CE3 and CE4, were isolated from C57BL/6J blastocysts. The ratio of normal diploid composition of these cell lines is above 70%. To examine the differentiation potential of the ES cells, the CE2 cells were injected subcutaneously into syngenic mice, and many kinds of differentiated cells were observed on the sections of the teratoma derived from this ES cell line. On the other hand, to test the chimeric ability of the ES cells, the CE2 cells were microinjected into the blastocysts of ICR mice, and a chimera was obtained among living pups. These results show that CE2 ES cells are pluripotent stem cells, which can differentiate into many kinds of cell types, and can be used as a cell system for further research.
基金supported by the grants from the National Natural Science Foundation of China (Nos.31621004,31501188 and 31422038)the Key Research Projects of the Frontier Science of the Chinese Academy of Sciences (QYZDY-SSW-SMC002)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDA16000000)
文摘In the field of developmental biology and regenerative medicine,mammalian interspecific chimeras have been proved very useful for investigating early embryonic development and the immune system establishment,and extended to a promising potential for human organ generation(Rossant et al.,1982).
文摘Objective To find out a proper way to detect green fluorescent protein (GFP). Methods Kidneys, livers and femurs from GFP transgenic mice and C57BL/6J wild type mice were employed for in vivo study. The samples were dehydrated with alcohol and acetone individually before embedding, then frozen, paraffin and resin sections were made for the detection of GFP. C3 P12 cells which derived from calvaria bone cells of GFP transgenic mouse were used for the detection of GFP in vitro. Cells were exposed to alcohol, acetone and PBS after paraformaldehyde fixation. Laser scanning microscopy was employed for GFP detection. Results In frozen sections, both kidney and liver samples which exposed to 4% buffered paraformaldehyde fixation had strong GFP signals, while GFP signal disappeared completely in fresh frozen sections without fixation. Much stronger GFP intensity was found in acetone treated samples than in alcohol treated paraffin sections, but without apparent difference in GFP intensity in acetone and alcohol treated resin samples. Acetone and alcohol made no difference in fixed C3 cells in different time courses. Conclusion Acetone treated paraffin sections are preferable for GFP detection.