Applications of Stem Cells

We are aware that different types of cells make up our body, but we usually forget to appreciate that all of these different cell types arose from a single cell, the fertilized egg. Stem cells from embryo can become any cell in the human body.Adult stem cells were thought to be restricted to produce differentiated cells, which were specific to the organs from which they were isolated but recently it was demonstrated that these stem cells, under certain conditions, can be induced to form other cell types.
The above principles are applied in various clinical applications.
Applications of stem cells:
• The main clinical application of stem cells is as a source of donor cells to be used to replace cells in transplantation therapy.
• The isolation of additional stem and progenitor cells is being developed for many other clinical applications like skin replacement, brain cell transplantation, treatment for diabetes, etc.
• Several biotechnology companies are developing different strategies of stem cell therapies.
Most scientists do not support human reproductive cloning (embryos altered during cell research) for obvious ethical reasons, but they do want to continue stem cell research for clinical applications under appropriate regulation and legislations with the hope of alleviating human suffering. Many researchers also see human embryonic stem cells as part of a long-term research program, with any sort of cell therapy being at least 5 or 10 years off.
The hope of using human embryonic stem cells for cell therapy has been driven in part by the great success of bone marrow transplants, in which a patient’s blood supply is regenerated from his own blood-making stem cells. But these cells are different from embryonic cells; they already exist in the adult body. Bone marrow transplants are a special case, but the general applicability of that to any other disorder is a very big step. Making the embryonic stem cells convert in the laboratory into specialized types — like liver or heart cells — is not straightforward or predictable. Cells that look and behave like human muscle-activating neurons can be generated with just a few chemical signals. But some cells, like the insulin-making cells of the pancreas, have proved extremely hard to grow.
Besides the technical difficulty of growing the precise type of cell needed for cell therapy, researchers face the theoretical problem that new replacement cells are likely to be vulnerable to the same disease that killed the patient’s cells in the first place. This is because ideally, a disease process must be understood and arrested before new cells are introduced.
Many researchers have come to see the primary benefit of human embryonic stem cells as models for human disease. The idea is to take a cell from a patient, convert it to embryonic form, and then make the embryonic cell mature into the type that goes awry in the patient’s disease, whether it be a dopamine-producing cell for Parkinson’s disease or an insulin-making cell for diabetes.
“Stem cell biology is just a rubric that applies to many things going on in biology,” said John D. Gearhart, a Johns Hopkins University stem cell expert. He “personally feel(s) that the beauty of these cells is that we’ll learn a lot about human biology and disease processes, and that that information will be more important than the cells themselves.”