Aim: To isolate and transplant germ celis from adult mouse testes for transplantation. Methods: In order to distinguish transplanted celis from endogenous celis of recipients, donor transgenic mice expressing green fl...Aim: To isolate and transplant germ celis from adult mouse testes for transplantation. Methods: In order to distinguish transplanted celis from endogenous celis of recipients, donor transgenic mice expressing green fluores cent protein (GFP) were used. Germ celis were collected from the donors at 10-12 weeks of age and spermatogonia were concentrated by percoll fractionation and transplanted into recipient seminiferous tubules that had been previ ously treated with busulfan at 5 weeks of age to remove the endogenous spermatogenic celis. Results: Twenty vveeks after the transplantation, a wide spread GFP signal was observed in the recipient seminiferous tubules. The presence of spermatogenesis and spermatozoa was confirmed in sections of 12 out of 14 testes transplanted (86 %). However, when germ celis were transplanted without concentration the success rate was zero (0/9). Conclusion: Germ celis from adult mouse testes can be successfully transplanted into recipient seminiferous tubules if the cell population is rich in spermatogonia and the percoll fractionation is useful in obtaining such a cell population.展开更多
<abstract>Prepubertal boys treated for cancer may exhibit impaired fertility in later life. A number of chemotherapeu tic agents have been identified as being gonadotoxic, and certain treatment regimens, such as...<abstract>Prepubertal boys treated for cancer may exhibit impaired fertility in later life. A number of chemotherapeu tic agents have been identified as being gonadotoxic, and certain treatment regimens, such as that used for Hodgkin's disease, are particularly associated with subsequent infertility. Radiotherapy may also cause gonadal damage, most notably following direct testicular irradiation or total body irradiation. Because of the varied nature of the cytotoxic insult, it can be difficult to predict the likelihood of infertility in later life. Currently it is not possible to detect gonadal damage early due to the lack of a sensitive marker of gonadal function in the prepubertal age group.Semen cryopreservation is currently the only method of preserving fertility in patients receiving gonadotoxic therapy. This is only applicable to postpubertal patients and can be problematic in the adolescent age group. At present there is no provision for the prepubertal boy, although there are a number of experimental methods currently being investigated. By harvesting testicular tissue prior to gonadotoxic therapy, restoration of fertility could be achieved following treatment, either by germ cell transplantation or by in vitro maturation of the germ cells harvested. Alternatively, rendering the testes quiescent during cytotoxic treatment may protect the germ cells from subsequent damage. In addition to the many scientific and technical issues to be overcome prior to clinical application of these techniques, a number of ethical and legal issues must also be addressed to ensure a safe and realistic prospect for future fertility in these patients.展开更多
Background Human embryonic stem (HES) cell derived from human blastocyst can be propagated indefinitely in the primitive undifferentiated state while remaining pluripotent It has exciting potential in human developmen...Background Human embryonic stem (HES) cell derived from human blastocyst can be propagated indefinitely in the primitive undifferentiated state while remaining pluripotent It has exciting potential in human developmental biology, drug discovery, and transplantation medicine But there are insufficieot HES cell lines for further study Methods Three oocyte donors were studied, and 3 in vitro fertilization (IVF) cycles were carried out to get blastocysts for the establishment of HES cell line Isolated from blastocysts immunosurgically, inner cell mass (ICM) was cultured and propagated on mouse embryonic fibroblasts (MEFs) Once established, morphology, cell surface markers, karyotype and differentiating ability of the cell line were thoroughly analyzedResults Four ICMs from 7 blastocysts were cultured on MEFs After culture, one cell line (cHES1) was established and met the criteria for defining human pluripotent stem cells including a series of markers used to identify pluripotent stem cells, morphological similarity to primate embryonic stem cells and HES reported else where. Normal and stable karyotype maintained over 60 passages, and demonstrated ability to differentiate into a wide variety of cell types Conclusions HES cell lines can be established from gamete donors at a relatively highly efficient rate The establishment will exert a widespread impact on biomedical research展开更多
文摘Aim: To isolate and transplant germ celis from adult mouse testes for transplantation. Methods: In order to distinguish transplanted celis from endogenous celis of recipients, donor transgenic mice expressing green fluores cent protein (GFP) were used. Germ celis were collected from the donors at 10-12 weeks of age and spermatogonia were concentrated by percoll fractionation and transplanted into recipient seminiferous tubules that had been previ ously treated with busulfan at 5 weeks of age to remove the endogenous spermatogenic celis. Results: Twenty vveeks after the transplantation, a wide spread GFP signal was observed in the recipient seminiferous tubules. The presence of spermatogenesis and spermatozoa was confirmed in sections of 12 out of 14 testes transplanted (86 %). However, when germ celis were transplanted without concentration the success rate was zero (0/9). Conclusion: Germ celis from adult mouse testes can be successfully transplanted into recipient seminiferous tubules if the cell population is rich in spermatogonia and the percoll fractionation is useful in obtaining such a cell population.
文摘<abstract>Prepubertal boys treated for cancer may exhibit impaired fertility in later life. A number of chemotherapeu tic agents have been identified as being gonadotoxic, and certain treatment regimens, such as that used for Hodgkin's disease, are particularly associated with subsequent infertility. Radiotherapy may also cause gonadal damage, most notably following direct testicular irradiation or total body irradiation. Because of the varied nature of the cytotoxic insult, it can be difficult to predict the likelihood of infertility in later life. Currently it is not possible to detect gonadal damage early due to the lack of a sensitive marker of gonadal function in the prepubertal age group.Semen cryopreservation is currently the only method of preserving fertility in patients receiving gonadotoxic therapy. This is only applicable to postpubertal patients and can be problematic in the adolescent age group. At present there is no provision for the prepubertal boy, although there are a number of experimental methods currently being investigated. By harvesting testicular tissue prior to gonadotoxic therapy, restoration of fertility could be achieved following treatment, either by germ cell transplantation or by in vitro maturation of the germ cells harvested. Alternatively, rendering the testes quiescent during cytotoxic treatment may protect the germ cells from subsequent damage. In addition to the many scientific and technical issues to be overcome prior to clinical application of these techniques, a number of ethical and legal issues must also be addressed to ensure a safe and realistic prospect for future fertility in these patients.
文摘Background Human embryonic stem (HES) cell derived from human blastocyst can be propagated indefinitely in the primitive undifferentiated state while remaining pluripotent It has exciting potential in human developmental biology, drug discovery, and transplantation medicine But there are insufficieot HES cell lines for further study Methods Three oocyte donors were studied, and 3 in vitro fertilization (IVF) cycles were carried out to get blastocysts for the establishment of HES cell line Isolated from blastocysts immunosurgically, inner cell mass (ICM) was cultured and propagated on mouse embryonic fibroblasts (MEFs) Once established, morphology, cell surface markers, karyotype and differentiating ability of the cell line were thoroughly analyzedResults Four ICMs from 7 blastocysts were cultured on MEFs After culture, one cell line (cHES1) was established and met the criteria for defining human pluripotent stem cells including a series of markers used to identify pluripotent stem cells, morphological similarity to primate embryonic stem cells and HES reported else where. Normal and stable karyotype maintained over 60 passages, and demonstrated ability to differentiate into a wide variety of cell types Conclusions HES cell lines can be established from gamete donors at a relatively highly efficient rate The establishment will exert a widespread impact on biomedical research
