We all started from one cell, so that one cell must have had the ability to become literally any type of cell in our body. As we grew, our cells became more specialized, because cells in your brain have very different jobs from those in your lungs, stomach, etc. This is necessary, but if you suffer an injury and there aren't any cells around that can replace the cells that got hurt, you may not be able to fully heal from that injury. But a stem cell, the type we all started as, CAN become any type of cell, and so could potentially heal almost any injury. The problem - where do they come from?
The answer is clear from their name - Embryonic Stem Cells. Getting ES cells requires the destruction of a 100-celled embryo, called a blastocyst, which is basically a ball of cells, and the latest point at which we are sure none of the cells have started to become specialized, or "differentiate". Current ES cell work is done on cells from excess embryos created by in vitro fertilization for infertile couples, who have decided they don't want them. While still potentially problematic, anyone with a serious issue with the destruction of those embryos should also have a big issue with the way IVF clinics would otherwise just destroy and throw them away. But, as I'll explain in this talk, stem cells from another person may not be helpful in treating you, because your immune system knows they came from somewhere else and can reject them. What you might actually need is a stem cell of YOURSELF, which would result from the much more ethically iffy practice of cloning yourself to create an embryo in order to harvest its stem cells to treat you, therapeutic cloning.
Participants in this seminar had already spent a whole session discussing some of the issues and implications of stem cell usage, but my point isn't to dwell on that part. In fact, my overall hope is that, by the time gene therapy is ready for any significant usage, we will have perfected an alternative to ES cells. There are two obivous ones - the blood from your umbilical cord when you are born contains some ES cells, so one could potentially freeze that blood for use later if you needed it. The other is adult stem cells. A good example of these is bone marrow, which is capable of producing numerous more specialized cells, most of your immune system. We THINK (but may be wrong, research is checking this out) that one couldn't, for instance, get brain from an adult bone marrow stem cell, but if you can get the right type of stem cell for the organ you want to treat, you would be set. Stem cells in adults are currently hard to find, but people are very interested in getting better at it, so this may be a real possibility later on. And without further ado, the talk I actually gave... :)
Start the talk with Slide 1
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