If your stem cells would acquire meristematic characteristics, discuss their positive and negative effects on humans.

Answer 1

Pros and Cons of Using Various Stem Cells

1. Abundant somatic cells of donor can be used
2. Issues of histocompatibility with donor/recipient transplants can be avoided
3. Very useful for drug development and developmental studies

	Adult Stem Cells	Embryonic Stem Cells	Induced Pluripotent Stem Cells
Pros

1. Trans differentiate and and reprogramming of these cells is possiblebut is not well studied
2. Thought to be less likely to be rejected if used in transplants
3. Success has already been demonstrated in various clinical applications
4. Can maintain and grow for 1 year or more in culture
5. Established protocols for maintenance in culture
6. ESCs are pluripotent cells that can generate most cell types
7. By studying ESCs, more can be learned about the process of development

1. Abundant somatic cells of donor can be used
2. Issues of histocompatibility with donor/recipient transplants can be avoided
3. Very useful for drug development and developmental studies
4. Information learned from the “reprogramming” process may be transferable for in vivo therapies to reprogram damaged or diseased cells/tissues

Cons

1. Limitations on ASC ability to differentiate are still uncertain; currently thought to be multi or unipotent.
2. Cannot be grown for long periods of time in culture
3. Usually a very small number in each tissue making them difficult to find and purify
4. Currently there is no technology available to generate large quantities of stem cells in culture

1. Process to generate ESC lines is inefficient
2. Unsure whether they would be rejected if used in transplants.
3. Therapies using ESC avenues are largely new and much more research and testing is needed
4. If used directly from the ESC undifferentiated culture prep for tissue transplants, they can cause tumors (teratomas) or cancer development 
5. Methods for ensured reproducibility and maintenance, as differentiated tissues are not certain.
6. Viruses are currently used to introduce embryonic genes and has been shown to cause cancers in mouse studies