Stem cells are now at the forefront of numerous discussions due to their potential use in the repair and regeneration of diseased and damaged tissues. Once considered a sci-fi dream, the possibility of using stem cells to push the boundaries of science and technology has crossed the realm of unlikelihood and jumped over to near certainty. However, this possibility has been met with much criticism and controversy due to the fact that there are perceived ethical boundaries that stem cell research seems to be knocking against.

What are stem cells?
Stem cells, considered the ‘building blocks’ of the human body, are undifferentiated cells which have the proliferative capacity to develop into other differentiated cell types. This capacity allows stem cells to become virtually any part of the body – skin, hair, nails, eyes, bone marrow, nerves, prostate, pancreas, etc., which makes the stem cell the source of all the human body’s organs and tissues. They have the capability to replicate themselves and develop into every type of cell.

The stem cell’s capability to create the human body from a single cell also extends to the repair of damages to tissues and organs. These capabilities provide a potential platform for the treatment of certain diseases such as Parkinson’s and Alzheimer’s, among others.

Stem cell analysis
Stem cells were first grown in cultures using mice embryos in 1981. This triggered extensive research into the subject although work on human stem cells within a laboratory setting did not have successful results until 1998, when human stem cells were isolated and grown.

When isolated, human stem cells may have the potential to provide a significant number of scientific breakthroughs and medical therapies. Therapies obtained from stem cells may be used to induce tissue repair and regeneration. Furthermore, the targeted delivery of specific genetic material can provide the necessary and effective treatment to a broad range of medical diseases and conditions. As such, it is important to assess whether human stem cells used in this manner are safe or not.

Tools used for stem cell analysis
To conduct a successful analysis of stem cells including sources and subtypes, there are several tools that may be used for the isolation, cultivation, differentiation, enumeration, gene expression and fluorescent analysis of stem cells, mostly hematopoietic, pluripotent, nonhematopoietic and progenitor cells. Most of these tools may be used in conjunction with one another so application to stem cells that originate from any source is seamless and effective. Embryonic stem cells also require culturing using cell-conditioned media or a feeder layer consisting of murine embryonic fibroblast. They may also require additives like bovine serum sourced from fetuses.

Two methods commonly used for stem cell analysis include fluorescence microscopy and flow cytometry, which also include standard and unique mono-clonal antibodies. This type of antibodies is effective for research on tissue regeneration. Flow cytometry allows simultaneous and non-invasive measurements of hematopoietic cell subsets and their transgene expression. Using greenish fluorescent protein sourced from the Aequorea Victoria jellyfish and red fluorescent protein from Discosoma coral, transplanted stem cells may be assessed for evidence of functional and anatomic integration. The fluorescence allows stem cells to be marked for easy identification later. This method is also effective for tracking the migration of transplanted stem cells from their site of origin to other tissues. That way, any stem cell transplantations that may migrate to non-target sites and any inappropriate tissue type differentiations may be observed and evaluated.

It is also necessary to use laboratory tools for stem cell analysis to ensure that any unregulated growth is detected. This type of differentiation may lead to the risk of tumor formations, which makes it necessary that studies regarding stem cell toxicology are carefully performed.

Challenges of using certain animal-sourced media in stem cell analysis
Components like murine embryonic fibroblast and fetal bovine serum may pose certain risks such as contamination and consistency problems. Certain factors such as the age, sex, health and diet of the source animal may also affect the culture, which makes it necessary to ensure that the media, whenever and wherever from they are sourced, should be consistent all throughout.

Maintaining the safety of stem cells
To ensure proper analysis of stem cells, it is necessary that standards in the practice and procedures of obtaining and culturing stem cells are imposed to ensure that the reliability, integrity and uniformity of the cells are in place. This is necessary in order to be able to obtain enough stem cells to be used for clinical studies. Stem cells, after all, are still biological entities that exhibit dynamic properties. As they extend and expand in culture, certain changes may occur in their intrinsic properties that may be unintentional and even useless. Everything from the seeding to the allowed density of the cells will affect how they will exhibit certain characteristics in culture. To this day, the type of human stem cells used in gene therapy is non-embryonic. Whether these cells can surpass current clinical challenges remains to be seen.