Science Buddies: "Ask an Expert"

Dear expert /sciencebuddy, :D
I chose the project Creating a Kidney: Using Stem Cells to bioengineer a vital organ for my science fair. I made a modification and so instead of using the exact information about the kidney nephron , I will be differentiating human pluripotent stem cells into Bowman's capsule cells, an essential type of nephron cell.
Im having a few problems. :cry:

First of all, I cannot find anywhere the supplemented soluble factors needed when creating human pluripotent stem cells into
Bowmans capsule. Can you help me with that as there is no research paper I can find to help me with that information. :( :cry:

Secondly, I also cannot seem to find the soluble and ecm proteins. This means I cannot use Amazonia without  the information, and I cannot use any of the 4 tables given because of these problems. Can you help me in any way?

Hi Sadi,

Don't cry any more--I think I found some information for you by searching 'bowmans capsule stem cells' on PubMed:

https://www-ncbi-nlm-nih-gov.ezproxy.hs ... d/16885410
J Am Soc Nephrol. 2006 Sep;17(9):2443-56. Epub 2006 Aug 2.
Isolation and characterization of multipotent progenitor cells from the Bowman's capsule of adult human kidneys.
Sagrinati C1, Netti GS, Mazzinghi B, Lazzeri E, Liotta F, Frosali F, Ronconi E, Meini C, Gacci M, Squecco R, Carini M, Gesualdo L, Francini F, Maggi E, Annunziato F, Lasagni L, Serio M, Romagnani S, Romagnani P.
Author information
Abstract

Regenerative medicine represents a critical clinical goal for patients with ESRD, but the identification of renal adult multipotent progenitor cells has remained elusive. It is demonstrated that in human adult kidneys, a subset of parietal epithelial cells (PEC) in the Bowman's capsule exhibit co-expression of the stem cell markers CD24 and CD133 and of the stem cell-specific transcription factors Oct-4 and BmI-1, in the absence of lineage-specific markers. This CD24+CD133+ PEC population, which could be purified from cultured capsulated glomeruli, revealed self-renewal potential and a high cloning efficiency. Under appropriate culture conditions, individual clones of CD24+CD133+ PEC could be induced to generate mature, functional, tubular cells with phenotypic features of proximal and/or distal tubules, osteogenic cells, adipocytes, and cells that exhibited phenotypic and functional features of neuronal cells. The injection of CD24+CD133+ PEC but not of CD24-CD133- renal cells into SCID mice that had acute renal failure resulted in the regeneration of tubular structures of different portions of the nephron. More important, treatment of acute renal failure with CD24+CD133+ PEC significantly ameliorated the morphologic and functional kidney damage. This study demonstrates the existence and provides the characterization of a population of resident multipotent progenitor cells in adult human glomeruli, potentially opening new avenues for the development of regenerative medicine in patients who have renal diseases.

Now, I know the above text may be all but impossible for you to understand with its technical jargon, but let me try to break it down for you. The paper is talking about human adult kidneys, but stem cells can be isolated from adult tissue and used to create various types of tissue like Bowman's capsules or glomeruli.

These stem cells are from the Bowman's capsule and are called parietal epithelial cells--PECs for short. This just means that they are a type of cell that lines a cavity or tubule. The key piece of info, I think, is the stem cell markers (proteins) that PECs produce CD24 and CD133, and the other factors, Oct-4 and Bml-1. The abstract goes on to say how these PECs could be induced to form functional tubules as well as other types of tissue.

Now, as to what these proteins and factors are called (in place of their abbreviations) you can look them up in Google and Wikipedia. For example, CD24 is a protein involved in cell adhesion: https://en.wikipedia.org/wiki/CD24
CD24 is a fairly common protein and I do not know exactly how it ties in with kidney stem cells but it is one of the proteins produced by the PECs and probably necessary for differentiation into other cell types.

I think Oct-4 is an essential factor in the stem cell transformation process: https://en.wikipedia.org/wiki/Oct-4
It is known as a transcription factor because it regulates the reading of messenger RNA (transcription) from the DNA template. This is important for gene expression. Oct-4 influences the expression of several genes involved in cell changes that could lead to a stem cell converting to something else--like a Bowman's capsule cell.

I don't want to overwhelm you with too much information, so I'll stop here. Take a look at this information and let me know if it helpful for you. There are more papers published about stem cells and kidneys that you can check out and if you have trouble understanding, let me know and I will try to explain.

Good luck!

Sybee

Thank you sooo much SciB Much appreciated. Will post other questions once Im ready with them. And sorry for replying after months I only viewed this today.

Hello again! Yes, you really need to read your messages sooner...

Think about the project and when you have some ideas and questions, post again and I will attempt to answer and make suggestions.

Sybee

Hello. I have changed things in the past few months.After asking my teacher I found out this project will be a theoretical science project.
My question is (can stem cells help to bioengineer a human kidney)

My hypothesis is (stem cells have the remarkable potential to develop into many different cell types or become another type of cell with a more specialized function, such as kidney cell).
And I was told it won't have variables
And now I'm focusing on my research plan only
im focusing on human induced pluripotent stem cells and how they are used to bioengineer kidney cell types >mainly podocytes.

And so I now have a problem with finding the effect of the cell media and substrate on hipscs differentiation into podocytes.

And

The experimental procedure. I'm totally feeling lost at the moment as I have 2 weeks left to complete my project.
And thank you soo much for everything.

Hello,
Thanks for updating me on your project. I will try to find some info to help you complete it.

Your teacher is correct--this would be considered a 'theoretical' project because you don't actually work with real cells in a lab--unfortunately.

Now, as I understand your proposal, you think human induced pluripotent stem cells (HIPSCs) can be induced to turn into a transplantable kidney, or at least into the podocyte precursor cells. So, the question is, what factors, proteins, chemicals, etc. do you need to add to your HIPSCs culture to stimulate them into differentiating into podocytes.

I did a search on Google Scholar and came up with one paper that sounds promising:


Article | Open | Published: 26 February 2019
Directed Differentiation of Human Pluripotent Stem Cells to Podocytes under Defined Conditions

Tongcheng Qian, Shaenah E. Hernday, Xiaoping Bao, William R. Olson, Sarah E. Panzer, Eric V. Shusta & Sean P. Palecek

Scientific Reportsvolume 9, Article number: 2765 (2019) | Download Citation

https://www.nature.com/articles/s41598-019-39504-8

I took a look at the method and the details and the paper is very technical and hard to understand without a lot of background knowledge. Clearly, cultured HPSCs can be turned into podocytes by exposing them to various chemicals and proteins in a culture medium designed to promote podocyte growth. The resulting cells act like podocytes but whether they could be transplanted into a human to regenerate a kidney is not clear.

I did see another reference to a paper on converting HPSCs into kidney 'organoids' which are small collections of cells that stick together to form a kidney-like structure--maybe a precursor to a full-sized organ.

Nature. 2015 Oct 22;526(7574):564-8. doi: 10.1038/nature15695. Epub 2015 Oct 7.
Kidney organoids from human iPS cells contain multiple lineages and model human nephrogenesis.
Takasato M1,2, Er PX1, Chiu HS2, Maier B2, Baillie GJ2, Ferguson C2, Parton RG2, Wolvetang EJ3, Roost MS4, Chuva de Sousa Lopes SM4, Little MH1,2,5.

This is a lot of technical information, but it should give you some places to start looking. It is very complex but it is possible to develop a recipe for what you want to do. Let me know when you have more questions.

Sybee