Not All Stem Cells Are Created Equal

            Aside from anyone who thought that the Large Hadron Collider experiments would go awry and inadvertently create a black hole that would doom us all to oblivion, I think most people would that agree that stem cell research is the most misunderstood and controversial area of scientific inquiry today.  As a proponent of stem cell research, I found that I was faced with a choice in how to address this problem:

1.     Angrily mumble to myself and shake my fist at the sky
2.     Write a condescending editorial disparaging anyone who disagrees with my point of view
3.     Attempt to plead my case for why stem cell research shouldn’t be so controversial and should be embraced by all

Although mumbling and being condescending can be fun at times, I decided to go with what was behind door number three.  It seems that most conversations involving stem cell research tend to devolve into shouting matches and people choosing sides rather than being open to discussion.  Even though that tactic seems to be working so well with congress, I’m going to go the other way and attempt the unthinkable by trying to be reasonable and objective.
            The elephant in the room and what most people first associate with stem cell research is the derivation of embryonic stem cells.  For those that believe blastocysts are people, there is little wiggle room in discussing moral ambiguities.  The one point of contention that I would bring up is the fallacy that embryos are destroyed for the purpose of stem cell research.  Embryonic stem cells that are used for research are sourced from in vitro fertilization (IVF) clinics, and these embryos would otherwise be destroyed and serve no purpose whatsoever.  The choice should really be seen as a decision of either using the cells for scientific research or just throwing them in the trash. 
            More importantly, embryonic stem cell research is but a portion of the research that falls under the stem cell research umbrella. Hopefully, many people are also aware of tissue stem cells that are sometimes referred to as adult stem cells.  Not many people would consider bone marrow transplants a controversial procedure, and yet this is classified as stem cell transplantation.  While adult stem cells have proven useful for clinical purposes, they are also less potent than embryonic stem cell research (in this case, potency is defined as the ability to differentiate into many different cell types). 
            This limited potency is not always seen as a bad thing, especially in the current state of cell replacement therapies.  While limited potency puts restrictions on the range of diseases and disorders that can be addressed, it also limits the possibility of teratoma formation after injection caused by undifferentiated cells (don’t Google “teratoma” unless you want to see some gnarly pictures, it’s basically an odd looking tumor comprised of many different tissues including hair, teeth, thyroid tissue, etc.).  Many clinical trials are currently underway using these adult cells, which can be seen by visiting ClinicalTrials.gov and searching for “mesenchymal stem cells” as keywords.
            A relative newcomer to the field of stem cell research and a cell type that is near and dear to my own research is the induced pluripotent stem cell (iPSC).  These cells are sourced from adult tissue such as skin or blood, and then converted to an undifferentiated stem cell-like state by a process developed by Shinya Yamanaka that won him a share of the 2012 Nobel Prize in Physiology & Medicine.  Basically, these are cells that have the differentiation potential of embryonic stem cells that are sourced from adult cells instead of blastocysts.  Therefore, they are the best of both worlds in that they sidestep the moral controversy while not compromising their potency.  The main drawback of these cells right now is basically the fact that they are relatively new (developed circa 2009) and we are not yet completely sure that they definitely behave exactly as embryonic stem cells would.  There is also the problem of the cells evolving in vitro selected qualities because of the fact that they have to be cultured in a lab throughout the transformation process.  This laboratory culturing may result in inadvertent selection for specific cells that contain mutations that allow them to thrive in a laboratory environment, which may make them poor representations of the original cell population.
            Putting aside the doom and gloom of uncertainty, one of the most exiting aspects of the iPSC revolution is the fact that many diseases can now be effectively modeled in vitro.  For example, if a patient has Alzheimer’s disease, the cells that are most affected by the disease are neurons.  Of course, it is impractical to take neurons from a living person (and not many people would volunteer).  So the fact that we can now take blood or skin samples from patients and transform them into the cell type that is most directly affected by a specific disease is a groundbreaking achievement.  Work is currently underway to explore not only the mechanisms of disease within the affected cell populations, but also whether or not certain disease states affect the development of affected cells, the susceptibility of those cells to toxic agents, and the efficacy of novel treatments.
            With all of these things considered, my one hope is that you will see that it is inappropriate to lump all of stem cell research into one single item to either accept or reject.  It is most definitely a complex and varied field of study that should be properly examined before any judgments are made.  Whether the immediate promise of stem cell research was oversold to the public or most people are just unfamiliar with the pace of basic research, impatience has lead to a misperception of stem cell research as being generally unproductive.  The fact is that we are just now entering a time where the fruits of stem cell research are making significant impacts in both the development of new clinical treatments and in the understanding of disease mechanisms.  Considering the fact that some of the most exciting work being done right now is based on a discovery that is only a few years old, I think it is safe to say that the best is yet to come.