| Accessibility | They are easily accessible and can be isolated from various tissues | Cell Sourcing | The cell-based therapies need the cells need to be expanded in large quantities while protecting their uniformity in activity and staying pathogen free. The use of human embryonic stem (ES) cells versus adult SCs is still a matter of debate. The current political decision makers strongly favoring adult stem cell option. |
| Potency | They are multipotent stem cells | Plasticity | Adult SCs have certain plasticity to transdifferentiate from one lineage pathway to another. Besides, instead of transdifferentiating with normal diploid chromosomal numbers, SCs may fuse with tissue-specific differentiated cells causing polyploidy. MSCs differentiation was reported to lead to tissue ossification or calcification in animal models which is also a potential risk in human use. |
| Volume | MSCs can easily expand to clinical volume in a suitable period of time | Safety Concerns of using transformed cells | In children with adenosine deaminase deficiency, the autologous transplantation of genetically modified hematopoietic stem cells was reported to lead to severe immunodeficiency followed by acute leukemia in some of the patients. Nerve cells implantation in Parkinson’s disease patients was reported the high rate of severe and uncontrollable dyskinetic activity as adverse effect. Also, myoblast implantation into the heart tissue showed adverse event of increased rates of cardiac arrhythmias. |
| Storage | MSCs can be stored for repetitive therapeutic usage | Choosing autologous or non-autologous human cells | Regardless of the chosen method, each treatment has important regulatory and practical difficulties, and logistics of delivery can be another issue, i.e. to maintain the uniformity of cells, to avoid any contamination during cell processing. |
| No Reported Safety issues | Clinical trials of MSCs so far haven’t shown adverse reactions to allogeneic MSC. | Maintenance of cell viability | The nutrient and oxygen delivery to the cellular implant is of vital importance for viability of the cells. It has been still in experimental stage to use the neovascular capillary bed in and around the cell implant and intravascular cell encapsulation implant approach not having use in human in clinics. |
| Effectiveness | Effectiveness of MSCs have been obviously documented in several clinical trials | | *The references used to compile the information for this table: 22, 33, 77, 78, 79, 80, 81. |