الفهرس 
Basics of Stem CellsOnly 14 pages are availabe for public view
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Abstract
A stem cell is an undifferentiated cell with undetermined function, which can differentiate into the three embryonic germ layers. The history of stem cell research started in mid 1800’s and since then researcher tried to make a much progress in that field, especially in last decades when new types of stem cells had been isolated and extend the field of clinical applications.
Transplantation of organs such as the liver and heart can be an option, but many are in short supply. Over the past decades, stem cell research has gained a lot of attention because it has the potential to fill this gap in human medical therapies.
Stem cells have the capability of self renewal either through symmetrical or asymmetrical division, other properties of stem cells include maturation, apoptosis, trafficking and being quiescent.
As regard types of stem cells, the 2 major categories include embryonic and adult stem cells:
- Eryonic stem cells are pluripotent cells, capable of being any cell in the human body and they are derived from the inner cell mass of pre-implantation poor quality blastocysts, obtained from in vitro fertilization treatment, which have been donated for research after informed concent. Although having high ability to renew themselves, they have disadvantages of immune rejection, tumorigenicity and surrounding ethical considerations.
- On the other hand, Adult stem cells are multipotent stem cells, arising from a wide range of adult tissues. Although they are found in small number and difficult to isolate, they have less ethical considerations and the problem of immune rejection can be avoided by using autologus cells.
- Other types include Fetal Stem Cells , Umbilical Cord Blood Stem Cells, Placenta and Fetal Membranes, Amniotic Fluid and Induced Pluripotent Stem Cells which are pluripotent cells derived from somatic cells.
- Stem cell research in animals has been an ongoing program with good results. A wide range of experimental studies have been done to find effective ways of therapy for different medical and surgical problems in pediatric population. However, only limited information is available with the use of stem cells in human beings.
- Stem cells have many applications in pediatric surgery with promising results. The use of cell therapy as a means of repopulating the liver has several advantages over whole organ transplantation. Mesenchymal stem cells proved to have a greater homing capability for the injured liver and modulated fibrosis and inflammation with paracrine effects and immunomodulatory properties on hepatic stellate cells and native hepatocytes in the treatment of the liver pathology.
- Esophageal tissue engineering could represent a valid alternative in esophageal replacement, thanks to biomaterial science and cellular biology. Enteric nervous stem cells derived from human gut mucosa represent a practical advance in treatment of enteric nervous system disorders such as Hirschsprung’s disease. Also, tissue engineering and stem cell therapy can be used in treatment of neurogenic bladder.