Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.3.1 (alkaline phosphatase)
 47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Human embryonic stem (ES) cells have been established either from fresh or frozen embryos. The recovery rates of undifferentiated human ES cells after cryopreservation with conventional slow-rate freezing and rapid-thawing methods are relatively low. The purpose of this study was to improve cryopreservation efficiency by modifying conventional methods with addition of trehalose. Immature oocytes donated from patients undergoing IVF treatment were utilized to generate blastocysts. One human ES cell line (named hES1) was established and characterized in detail. The hES1 cells expressed regular human ES cell markers, including stage-specific embryonic antigens SSEA-3, SSEA-4, tumour rejection antigens TRA-1-60, TRA-1-81 and octamer-binding transcription factor Oct-4 with high levels of alkaline phosphatase and telomerase activities. Cells could be differentiated to form teratomas in vivo. With slow-rate freezing and rapid-thawing methods modified by adding trehalose, the recovery rate of undifferentiated hES1 cells has been greatly improved from 15 to 48%. Cells retained pluripotency with normal karyotype after thawing. The results indicated that the use of trehalose is efficient and convenient for cryopreservation of human ES cells.
 ...
PMID:Improved cryopreservation of human embryonic stem cells with trehalose. 1641 38

Bovine embryonic stem (bES) cell lines reported to date vary in morphology and marker expression, such as alkaline phosphatase (ALPL), stage-specific embryonic antigen 4 (SSEA4), and octamer-binding transcription factor-4 (OCT4), that normally are associated with the undifferentiated, pluripotent state. This chapter introduces the methods of isolating and maintaining bovine ES cells. These bovine ES cells grow in large, multicellular colonies resembling the mouse ES and embryonic germ (EG) cells, as well as human EG cells. Throughout the culture period, most of the cells within the colonies stain positive for ALPL and cell surface markers SSEA4 and OCT4. The staining patterns of the bES cells are identical to those of the blastocysts fertilized in vitro (IVF), yet different from most previously reported bovine ES cell lines, which are either negative or not detected. After undifferentiated culture for more than 1 year, these cells maintained the ability to differentiate into embryoid bodies and derivatives of all three EG layers, thus demonstrating their pluripotency. In addition to bES from IVF, this chapter introduces two methods of generating blastocyst stage embryos other than in vitro fertilization, which are parthenogenetic activation and somatic cell nuclear transfer for the potential application of generation "patient-specific" ES cells.
 ...
PMID:Bovine embryonic stem cells. 1714 Oct 27

In the present study, we have characterized an isolated population of porcine bone marrow mesenchymal stem cells (MSCs) for multilineage commitment and compared the developmental potential of cloned embryos with porcine MSCs and fetal fibroblasts (FFs). MSCs exhibited robust alkaline phosphatase activity and later transformed into mineralized nodules following osteoinduction. Furthermore, MSCs underwent adipogenic and chondrogenic differentiation by producing lipid droplets and proteoglycans, respectively. Primary cultures of FFs from a female fetus at ~30 day of gestation were established. Donor cells at 3-4 passage were employed for nuclear transfer (NT). Cell cycle analysis showed that the majority of MSCs in confluence were in the G0/G1 stage. Cumulus-oocyte complexes were matured and fertilized in vitro (IVF) as control. The cleavage rate was significantly (P<0.05) higher in IVF than in NT embryos with MSCs and FFs (84.54.6% vs. 52.25.4% and 50.85.2%, respectively). However, blastocyst rates in IVF and NT embryos derived from MSCs (20.62.5% and 18.43.0%) did not differ, but were significantly (P<0.05) higher than NT derived from FFs (9.52.1%). Total cell number and the ratio of ICM to total cells among blastocysts cloned from MSCs (34.45.2 and 0.380.08, respectively) were significantly (P<0.05) higher than those from FFs (22.65.5 and 0.180.12, respectively). Proportions of TUNEL positive cells in NT embryos from FFs (7.31.8%) were significantly (P<0.05) higher than in MSCs (4.61.3%) and IVF (2.50.9%). The results clearly demonstrate that multipotent bone marrow MSCs have a greater potential as donor cells than FFs in achieving enhanced production of cloned porcine embryos.
 ...
PMID:Enhanced development of porcine embryos cloned from bone marrow mesenchymal stem cells. 1718 68

Since the first human embryonic stem cell (hESC) line was generated by Thomson et al. (in Science 282:1145-1147, 1998), hundreds of hESC lines have been reported by different labs, providing resources for basic research and regenerative medicine as well. However it has been widely recognized that hESC lines varied on their properties, in terms of gene expression profile, epigenetic modify profile, and differentiation tendency. Generation of more hESC lines will largely enhance our knowledge of hESCs innate character. In this current work, we reported the generation of HN4, a hESC line derived from grade III IVF human embryo by using a mixture of human foreskin fibroblast (HFF) and mouse embryonic fibroblast (MEF) as feeder layers, and a whole-mechanical method in inner cell mass (ICM) isolation. HN4 satisfied the criteria of hESCs pluripotency, with high expression of hESC surface markers (SSEA-3, SSEA-4, TRA-1-60, TRA-1-81), transcription factors (OCT-4, NANOG, REX-1), and alkaline phosphatase. It is able to differentiate to three germ layer derivatives when cultured in vitro, or in teratoma formation. Moreover, it displayed promising potential in neural differentiation under a proper culture condition, suggesting the advantage of HN4 in further investigation. Additionally, the whole-mechanical protocol for ICM isolation facilitates hESC line generation for its ease to handle.
 ...
PMID:A whole-mechanical method to establish human embryonic stem cell line HN4 from discarded embryos. 2097 54