Science Buddies: "Ask an Expert"

Is there a way to make human eggs out of stem cells? Can you also make human sperm from stem cells and fertilize the sperm and egg together to make a healthy zygote?

Hi,

Those are some very good questions! We do not currently have all the answers to those questions, but scientists are trying to answer at least some of them:

Is there a way to make human eggs out of stem cells? http://www.nytimes.com/2012/02/27/healt ... .html?_r=0 I think you can use the researchers names in the article to find their original paper or their personal/professional website for more information.


Can you also make human sperm from stem cells? This was recently in the news (I read it the other day!): http://www.bbc.co.uk/news/world-us-canada-19879113

... and fertilize the sperm and egg together to make a healthy zygote? For humans, this is not allowable in the USA or most other countries. There may be scientists out there working on this, but most consider it unethical. There is probablly similar work being done on animals, for the purpose of producing animals for use in industrial applications (like the fod industry, etc).

Please let me know if I can help you further!
Tonya

Hi Tonya! Thank you for your reply, my partner and I have found it very helpful. Instead of using human stem cells, my partner and I have decided to use animal stem cells, like a frog or rat, for ethical reasons. In order to differentiate the stem cells would we have to add a hormone? If so, would we get the hormone from the animal or would we need to get it from a lab?

lety95 wrote:Hi Tonya! Thank you for your reply, my partner and I have found it very helpful. Instead of using human stem cells, my partner and I have decided to use animal stem cells, like a frog or rat, for ethical reasons. In order to differentiate the stem cells would we have to add a hormone? If so, would we get the hormone from the animal or would we need to get it from a lab?

Great follow-up questions.

For animal stem cells, the most popular to use are from mice. Generally the differentiation signals are proteins put into the cell culture medium. The specific mix depends on the cell type you want to differentiate into. You can look into those original papers to see how they did it.

When you need to buy the proteins, you will get them from a laboratory supply company. They get them from different sources (for different reasons) - some are isolated directly from animals and some are made recombinantly. In general, the protein sequences are highly conserved, so you can use human protein on mouse cells and it will work - not ALWAYS true, but usually. So don't be worried if you cannot find mouse proteins you need.

Let me know how else I can help. This is a great topic - so new!
Tonya

Hi Tonya! I am Lety95's partner for this project. This is what we are planning on doing so far: We want to take mouse somatic skin cells and, using IPS technology, transform them into embryonic stem cells. I believe this is of less controversy than taking stem cells directly from the mouse, but I am not positive. We still need to check the regulations for this science fair. After we turn the skin cells into the pluripotent stem cells, we can then create an egg, somehow. As you can see, we still have much more research to do, but we are wondering if this sounds like a reasonable experiment. We have contacted a university to see if they can help us with equipment, so hopefully that will not be an issue.

chelsey95 wrote:Hi Tonya! I am Lety95's partner for this project. This is what we are planning on doing so far: We want to take mouse somatic skin cells and, using IPS technology, transform them into embryonic stem cells. I believe this is of less controversy than taking stem cells directly from the mouse, but I am not positive. We still need to check the regulations for this science fair. After we turn the skin cells into the pluripotent stem cells, we can then create an egg, somehow. As you can see, we still have much more research to do, but we are wondering if this sounds like a reasonable experiment. We have contacted a university to see if they can help us with equipment, so hopefully that will not be an issue.

Hi, yes, what you describe is definately possible, however it may take some time. You should look into the details of your protocols right away and determine if you have the time. The reprogramming of skin cells may take weeks to months depending on the technology you use. Then inducing differntiation to egg cells - the protocol is in that paper. Did you get to read it yet?

I want to correct your teminology in the first sentence: "... transform them into embryonic stem cells." - Later, you correctly referred to them as pluripotent stem cells (or you could have called them induced pluripotent stem cells = ipsc), but they are not embryonic stem cells. Embryonic stem cells are another type of pluripotent stem cells - but they are isolated right from growining embryos, which is why there is so much controversy over their use.

We have until January to carry out our experiment, but our procedure needs to be submitted by October 29, unfortunately, because of the use of a vertebrate animal. I did read the paper you are referring to, and it was definitely helpful. My partner and I have again changed our project slightly. Sorry if we are confusing you at all because we keep changing the experiment. Now, we would like to start off with pluripotent stem cells that we buy from a lab, and using the same procedure, make an egg, or multiple eggs. Before, we had planned on starting with skin cells and turning them into stem cells. Transforming skin cells into stem cells and then the stem cells into an egg seemed like 2 experiments in one, so we have decided to begin our project with stem cells that we will buy. I have checked the regulations, but am slightly confused on whether we can go through with this project. If not, then my partner and I can change our procedure in various ways to fit the protocol, like using an invertebrate animal instead of a vertebrate. And thank you for the terminology correction, I always appreciate good criticism.

chelsey95 wrote:We have until January to carry out our experiment, but our procedure needs to be submitted by October 29, unfortunately, because of the use of a vertebrate animal. I did read the paper you are referring to, and it was definitely helpful. My partner and I have again changed our project slightly. Sorry if we are confusing you at all because we keep changing the experiment. Now, we would like to start off with pluripotent stem cells that we buy from a lab, and using the same procedure, make an egg, or multiple eggs. Before, we had planned on starting with skin cells and turning them into stem cells. Transforming skin cells into stem cells and then the stem cells into an egg seemed like 2 experiments in one, so we have decided to begin our project with stem cells that we will buy. I have checked the regulations, but am slightly confused on whether we can go through with this project. If not, then my partner and I can change our procedure in various ways to fit the protocol, like using an invertebrate animal instead of a vertebrate. And thank you for the terminology correction, I always appreciate good criticism.

Hi,

Yes, that is part of science - modifying your work as needed before you start. That is good - you can start with PSCs. I understand the procedure you are going to do, but I wonder what the question is that you are trying to answer?

It seems that our project will not work. We changed our project again to simply growing stem cells in different environments, but we found out that due to the cost of stem cells, we cannot go through with this project. We contacted a few different universities and they all say they cannot donate stem cells. So,unfortunately, we are completely changing our idea away from stem cells. We do not know what we are doing yet, though.

chelsey95 wrote:It seems that our project will not work. We changed our project again to simply growing stem cells in different environments, but we found out that due to the cost of stem cells, we cannot go through with this project. We contacted a few different universities and they all say they cannot donate stem cells. So,unfortunately, we are completely changing our idea away from stem cells. We do not know what we are doing yet, though.

Hi,
Oh, I am sorry that has happened to your project. Yes, purchasing stem cells is very expensive. I am sure you will find another great project that sparks your interest. You can try the Science fair Project Wizard: https://www.sciencebuddies.org/science- ... deas.shtml

Good Luck!
Tonya

Thank you for all your help Tonya!