It's been a little while since my last post, so I figured I would share a bit of good news to kick off the new year. An article in which I am a co-author was just published in eLife on the topic of lincRNAs (long intergenic noncoding RNAs) and their role in proper brain development. I'm probably a bit biased, but I think it's a really fascinating study and further proof that what we once considered "junk" within the genome is not only important, but in many cases vital for survival.
Feel free to give it a read if you are so inclined, as one of the major reasons why the lead author chose eLife as a journal was the fact that their articles are open-access and free for all to read without a subscription, as I would contend that all science is meant to be. You can find the article here: http://elife.elifesciences.org/content/2/e01749
I recently contributed a guest post to the Integrative Academic Solutions Blog entitled "Lessons From Beyond the Bench". In the post I discuss my background and the path that brought me to where I am today. I think it turned out pretty well, so if you haven't already checked it out, you can read it here:
Feel free to leave me a comment and let me know what you think.
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.
Have you ever randomly had a really good idea, only to realize someone else had already thought of it a few years ago? I had that experience recently when I was listening to a StarTalk radio show podcast hosted by Neil deGrasse Tyson in which they were discussing the logistical nightmares of planning a manned trip to Mars. The major tripping points seemed to be the amount of radiation that the astronauts would be subjected to, and also the amount of fuel necessary to complete a round trip. In discussing the latter of these problems, I was surprised to find that the Dutch firm Mars One has already received over 1,000 volunteer applications after announcing its plans for a one-way trip (suicide mission) to Mars in 2023 (1). For the rest of mankind that would rather not be martyred in the name of science, I felt that my idea would be the perfect solution: hitch a ride on an asteroid. Of course, a quick Google search revealed that I was not the first to think of this (2), but I still think it is a neat idea worth exploring. With that being said, now is probably a good time for a disclaimer: I am not an astrophysicist, astrobiologist, or astro anything for that matter. My expertise is in the field of cell biology so it’s probably a good idea to take my opinions of space travel with a grain of salt.
The problem of radiation exposure:
Current radiation shielding used for any type of aircraft needs to be lightweight in order to minimize fuel consumption and to also be conducive to flight. Unfortunately the only type of radiation shielding that would be effective for such an extended trip to Mars would be much too heavy to be used on a space shuttle given current technology. In fact, the lighter aluminum-based shielding that we currently use for space travel can actually result in secondary radiation when it is hit by cosmic rays, and this secondary radiation may be more dangerous than the cosmic rays themselves! Also, by “extended trip”, I do mean quite a long journey, as Dennis Tito’s recently announced plans for a Mars fly-by mission in which they won’t even land on Mars is estimated to take 501 days. When you also factor in landing on Mars, you would need to add at least another three months on top of those 501 days due to the fact that you would have to wait for proper Mars-Earth alignment before embarking on your return trip (3). How could these problems be addressed by riding an asteroid? By landing on an asteroid, the spacecraft could “duck down” into a crater that will shield the astronauts from radiation, and it would also be feasible to develop a tunneling technology in order to seek an even greater degree of radiation shielding. Any crater that is deep enough to provide a good cover of shade would also theoretically provide ample mass shielding from cosmic rays.
The problem of fuel consumption:
The paradox of fuel consumption in space travel is that the heavier you are, the more fuel you need; and the more fuel you are carrying, the heavier you are. Much like Marty McFly in Back to the Future grabbing on to car bumpers to propel his skateboard (AKA “skitching”), landing on an asteroid would allow the spacecraft to utilize the momentum of the already moving object, mitigating the need for fuel-consuming self propulsion. The fuel consumption concerns would then be the amount of energy required to move from planet to asteroid, asteroid to planet, planet to asteroid, asteroid to planet. Additional fuel consumption would be needed to maintain life support, but the total distance of self-propelled travel should be greatly reduced.
Why this may not be such a good idea:
The most glaring problem with what I think I will call “The Asteroid Skitching Strategy” is that we don’t really have any control over where the asteroid is specifically going, which seems to be a problem if you have a specific destination in mind. Sure, we can project where we think the asteroid will be, but a slight change in trajectory could doom all astronauts on board with too little fuel to abort the mission or change course. The reality of waiting for an asteroid that is the right size and is “going our way”, may turn out to be more than a minor detail when dealing with an otherwise highly controlled mission. Add in the fact that you may need to rely on a completely different asteroid for the return trip that also has all of the correct characteristics and trajectory, and the odds may not be in our favor. A hitchhiking strategy of jumping from asteroid to asteroid instead of waiting for the perfect trajectory could help, but adding in more takeoffs and landings will definitely affect the fuel consumption considerations.
It’s also (as far as I know) not all that easy to land safely and reliably on an asteroid. Landing on the moon seemed like a pretty big deal and there are still countries today that can’t do it successfully with today’s technology. I’m guessing that landing on an object that is moving much faster, is much smaller, and is much more morphologically dynamic would up the ante just a bit. All in all to a layperson it seems basically feasible to pool the resources of the asteroid mining groups and Mars exploration groups in order to develop more robust and realistic short term goals, however it seems like it’s going to be a very iterative process and I’m not holding my breath for a successful attempt within the next 20 years. In other words, I’m not volunteering to be on board for the first try.