Scimitar Equity Blog

Referencing our previous 3 blogs; I thought I would back-up my posts with a few stem cell topic definitions (2 of 3 blogs); these were  extrapolated from various websites and a sector report I have put together as well as excerpts from the International Society for Stem Cell Research.

What is a stem cell line?

• A stem cell line is composed of a population of cells that can replicate themselves for long periods of time in-vitro, meaning out of the body.  These cell lines are grown in incubators with specialized growth factor-containing media, at a temperature and oxygen/carbon dioxide mixture resembling that found in the mammalian body,
• Embryonic stem cell lines, both human and mouse, can be grown indefinitely in-vitro if the correct conditions are met.  Importantly, these cells continue to retain their ability to form different, specialized cell types once they are removed from the special conditions that keep them in an undifferentiated, or unspecialized, state.

What is an embryonic stem cell?

• Embryonic stem cells are derived from the cells that make up the inner cell mass of the blastocyst.  Both mouse and human embryonic stem cell lines exist.  Mouse embryonic stem cells are capable of generating any and all cells in the body, under the right conditions.  Therefore, they are said to be pluripotent and have unlimited potential as far as growth and differentiation.  The cells divide continuously in tissue culture dishes in an incubator, but at the same time maintain the ability to generate any cell type when placed into the correct environment to cause their differentiation, 
• Human embryonic stem cell lines are currently being studied and several research teams are working to determine whether or not they possess the same properties as mouse embryonic stem cells.  Because human embryonic stem cells were isolated relatively recently, and therefore we know less about them, it is currently more difficult to work with human systems than mouse,
• However, scientists are making remarkable progress that could ultimately lead to therapies to replace or restore damaged tissues using these human cells.

 What is an adult stem cell?

• Adult stem cells are distinct from cells isolated from embryos or fetuses and are found in tissues that have already developed, as in animals or humans after birth.  These cells can be isolated from many tissues, including brain.  However, the most common place to obtain these cells is from the bone marrow that is located in the center of some bones.  The marrow is harvested from human donors at the iliac crest (the back of the upper hip bone), 
• There are different types of stem cells found in the bone marrow, including hematopoietic stem cells, endothelial stem cells, and mesenchymal stem cells.  It has long been known that hematopoietic stem cells form blood, endothelial stem cells form the vascular system (arteries and veins), and mesenchymal stem cells form bone, cartilage, muscle, fat, and fibroblasts,
• Recently a theory of “stem cell plasticity” has been put forth, which suggests that some adult stem cells may have a broader potential to form different cell types than was previously suspected.  That means cells from the bone marrow, originally thought to be purely blood-forming cells, may contribute to regeneration of damaged livers, kidneys, hearts, lungs and other organs.  Though this field is extremely exciting, it is highly controversial in the scientific community and needs additional carefully documented research to understand the full potential of the adult stem cells, and in particular how they compare to embryonic stem cells.

Bottom Line:  Reiterating, the stem cell research industry is being given a lift by “evolving” the restrictions of government funding.  According to the National Institutes of Health (NIH), out of 88 lines 21 were actually available. Researchers worldwide are working to identify alternative sources for stem cells; the viability and potency of these sources will be of key importance.