GCSE Biology - Stem Cells in Medicine

in this video we're looking at the use of stem cells in medicine so we'll start by explaining how stem cells can be used to treat conditions like diabetes and paralysis then we'll look at some of the risks involved in the process and finally we'll consider the ethical implications and see why some people think that we shouldn't use stem cells in this way before we start i want to quickly recap what stem cells are and there are really two important features about them that you need to remember one they can divide by mitosis to produce more

cells and two they can differentiate into different types of specialized cells now there are lots of different kinds of stem cells but the main two that you need to know about are embryonic stem cells which are found in the early embryo and can differentiate into absolutely any type of specialized cell and adult stem cells which are found in the bone marrow of people of all ages but can only differentiate into different types of blood cells the other bit of background we need to know for this topic is that lots of conditions are due to faulty

cells which just means cells that are damaged in some way or that don't work properly for example type 1 diabetes is caused by damage to the pancreas cells that normally produce insulin while paralysis is sometimes caused by damaged nerve cells and sickle cell anemia is caused by misshapen red blood cells so if you think about it if we could somehow replace these faulty cells with properly working cells then we could treat these conditions and this is the basic idea behind using stem cells in medicine we use stem cells to replace the faulty cells the most

common technique for actually doing this would be for scientists to extract embryonic stem cells from early embryos grow them in a laboratory and then stimulate them to differentiate into whichever type of specialized cell that we want so that we can then give them to the patient to replace their faulty cells for example in the case of a diabetic patient where the issue is that some of their pancreas cells have been damaged and don't produce insulin anymore these scientists would take some embryonic stem cells and grow them in a laboratory then stimulate them to differentiate in

the pancreas cells so that they can produce insulin and then they could inject those cells into the patient's pancreas where they could continue to divide and produce the insulin that the patient needs or in a similar way if we wanted to treat somebody for paralysis we could use the same process to produce healthy nerve cells or to treat them for circle cell anemia we would differentiate them into healthy blood cells now this method of using embryonic stem cells sounds great in theory but in practice it has a couple of drawbacks the first is the fact

that it requires embryonic stem cells because remember those are the only ones that are able to differentiate into any type of cell however because embryonic stem cells only come from embryos there's a very limited supply of them and there are also some ethical issues around using them as we'll see later the second drawback is the idea of rejection because the embryo and the patient have different genomes the patient's immune system may reject the stem cells which means it tries to destroy them because identifies them as foreign we can reduce the risk of this happening by

giving the patient medications to suppress their immune system but it doesn't always work and often has side effects now an alternative to this we should overcome both of these issues would be to use adult stem cells instead these are easy to get hold of and also won't cause rejection because they can be taken from the patient themselves the downside of adult stem cells though is that they can only differentiate into different types of blood cells so while we could use them to treat blood cell disorders like sickle cell anemia we couldn't use them to treat

other conditions like diabetes or paralysis one caveat to this though is that there is some new research exploring how we could use adult stem cells to produce any type of cell regardless of which type of stem cell we use though there are two potential risks involved with using stem cells namely virus transmission and tumor development virus transmission refers to the idea that if the donor stem cells are infected with a virus either before they were taken by the scientists or while they were in the lab then when they're transferred into the patients they had also

transferred that virus which could then infect the patient and cause even more problems on the other hand tumor development is the idea that because stem cells can divide so quickly there's a chance that they could get out of control once they've been transplanted into the patient and so they could go on to develop into a tumor or a cancer okay so the final thing we discover is the ethical objection to using embryonic stem cells this is the idea that the human embryos that are being used have the potential for human life and so on religious

or moral grounds some people object to their use in research on the other hand other people think that the benefits of curing existing people who are suffering is more important than the rights of embryos either way though an important point to remember is that the embryos that are used are usually the unwanted ones from fertility clinics that would otherwise have been destroyed so they probably wouldn't have developed into human anyway also governments normally heavily regulate this area of research with some countries banning it completely in the uk embryonic research is legal but it's tightly controlled

and scientists have to follow strict rules hey everyone amadeus here i just wanted to let you know that we also have a learning platform where you can watch all of our videos practice what you've learned with questions and keep track of all of your progress for both the sciences and maths it's completely free so if you haven't already you can check it out by clicking on our logo here on the right or if you'd like to do the lesson for this particular video we put the link to that in the description down below we've also

arranged all the videos for this subject in a playlist for you here that's all though so hope you enjoy and i'll see you next time thanks