Q&A with Dr. Aaron Gardner

[joachim]

this is a thread for questions to Dr. Aaron Gardner (Team Jahoda).
Questions regarding hair cloning, DP cell culturing etc.

Thanks for your time, Dr. Gardner. It's a great pleasure to have you here.

[Arashi]

First post and explanation from Dr Gardner:

I'm not sure if sophisticated is the word, especially not in relation to myself But I'm happy to come and discuss my work (and my understanding of others work) anywhere, it's part of why I enjoy doing science .

To answer your questions it might be best first to lay out our current aims/understanding:

1) Rat whisker dermal papilla (DP) can be isolated, cultured and re-implanted into the skin to induce new follicles.

2) Fresh, whole human DP can be re-implanted to induce a follicle.

3) 2D cultured human DP lose this ability to induce follicle.

4) Dr Higgins in her paper demonstrated this nicely by by performing a micro-array, (a technique which compares, in bulk, gene expression between two or more samples). She showed that there was significant variation in several thousand genes between in vivo DP and 2D cultured DP (Fig 2A of her paper). http://www.pnas.org/content/early/2013/10/16/1309970110

5) She also demonstrated that 3D culture of human DP restored ~40% of the in vivo DP genetic character that was lost in 2D culture (Fig. 4C)

6) These 3D spheres were able to induce the formation of follicle structures from 5 of 7 donors with an efficiency ranging from 10-60% (i.e 10 spheres - 1 follicle structure = 10% efficiency).

So we want to take this further and there are several areas that we want to look at:
7) Improve efficiency, use more accessible cells, use only adult human tissues and develop a "quick" non-animal model assay.

8) Efficiency - Further restore in vivo DP character to 3D DP cultures, we are attempting to do this by coating the DP spheres with epithelial cells, to mimic the interactions that are occurring in vivo (Dr Higgins explained this really well in her talk). These dermal-epidermal interactions are key in follicle development and subsequent hair cycling. See also: http://www.hairtx.com/files/2014/03/peg.gif this is the interaction that we're attempting to mimic in our cultures.

9) Accessible cells - Attempt to restore DP character to non DP cultures. We are looking at the dermal sheath (DS) as we think they are more similar in character to the DP than dermal fibroblasts (DF). But this is a stepping stone to using DF as the Rendl group are attempting. See "P202 (SY10) REPROGRAMMING REGULAR SKIN FIBROBLASTS INTO HAIR INDUCING DERMAL PAPILLA CELLS Carlos CLAVEL" from WCHR2014. We are doing this by adding genes that Dr Higgins identified in her paper, into DS and seeing if we can make them DP like.

10) Adult tissues - The majority of studies which demonstrate inductivity either use mouse or neonatal human epithelial cells/tissue. This obviously wont apply in patient so we need to demonstrate inductivity in a less "competent" tissue.

11) Quick assay - we need to screen for a lot of things, we need a quick, easy and cheap assay to achieve this. None of the current assays tick these boxes.

So what do I show?:
12) Efficiency - Epithelial coating restores markers of inductivity that are not seen in dermal only spheres, the populations are interacting, this is great and we hope to repeat Dr Higgins microarray experiment and see if we further restore character. When this works, it works really well. BUT the efficiency of coating is poor, a lot of the time the epithelial cells don't stick to the dermal model, so no improvement in inductivity, we're not sure why this is but we are trying other methods of coating, isolation epithelial cells and epithelial cell populations.

13) Accessible cells - A better option than above, but currently none of the factors we have screened have restored DP character. We have lots more factors and will move onto multiple factor screens as well.

14) Adult tissues - All our work is progressing using adult tissues, but we have yet to try our new cultures in a mouse model, we will do so shortly when we have our ideal double-sphere and any promising DS-DP .

15) Quick model - This has worked out really nicely, we have a new model we can use in the lab to see if our spheres induce the epithelium to grow down into the dermis of our gels, which is reminiscent of initial follicle formation.

Sorry for the wall of text, but I think it shows our thinking nicely. Other groups have differing ideas and it was great to see them at the WCHR and to see what it is that the other groups are up to. We can then apply the nice bits of their thinking to our models (and hopefully they might use some of our ideas ).

To answer the other key question of "when". To be honest I don't know, every year we make progress as do all the other groups. I don't really believe in this "5 years" time thing, as I honestly think one group will crack it, and it will appear very rapidly after that. Look out for papers using adult only human tissues, non follicle derived dermal cells and with high reproducibility those are the ones that are going to have the widest applications.

Thanks a lot for taking the time to come onto this forum to answer some questions dr Gardner, VERY much appreciated !!

And to everybody: please keep this thread ontopic, no offtopic discussions here please !!

[Arashi]

Sheets posted by dr Gardner:

https://creative.adobe.com/link/41dd32a9-59ff-4cbc-9954-d6b374a372c4

[Arashi]

Q:

actually, i'm a bit confused aaron from your sheets i get it that you guys restored hf inductivity by dermal/epidermal interactions so you're trying to make the dp cells think they're still in the skin, right ? However that didnt work as well as you had hoped since the outcome quality was very variable, right ? Can you maybe elaborate a bit on this ?

a:

yes, when we transplant the dp spheres into the skin they signal to the epidermis, the epidermis forms a placode and signals back down to the sphere.

The epidermis then grows down into the dermis and encapsulates the sphere giving rise to the follicle structure. At this point the interactions between the dp and hair follicle epithelium gives rise to the hair shaft.

This is a really important point, the dermal sphere is not a dermal papilla until it has been encapsulated by a competent epithelium.

When we manage to encapsulate our dp sphere with epithelial cells then we see markers of infuctivity that are normally only seen in the papilla in vivo (they are not seen in uncoated dp spheres). So the technique works really well. But, a lot of the time the epithelium doesn't stick to the dp sphere, if it doesn't stick we don't see these markers being turned on. So we need to figure this out, then assay these double spheres in a follicle forming assay.

[joachim]

the first important question, which often appears in our discussions but nobody is able to really answer it scientifically:

what is it all about with the sebaceous gland? Is it required during the hair cloning process to also create a seb. gland along with the whole follicle or can it be assumed that a lab-grown follicle would attach to one of the many exisiting seb. glands in the bald scalp instead?
Because we never heard of researchers that they are also trying to create the seb. glands in lab, and many people state a follicle without the gland is no real follicle. What is your opinion about it?

a dump question: is the seb. gland even required for hair at all? What would happen if you implant a lab-grown hair into the scalp, and the follicle wouldn't attach to a seb. gland?
it is often said that the seb. gland keeps the hair moist and soft, but isn't it more harmful than useful =D it creates a lot of sebum which is always bad for the skin, and probably also for the follicle, as the gland also does DHT conversion, where the DHT then moves down to the follicle.
in other words: isn't the seb. gland just a bad byproduct of the nature? (like the blind gut?) =D

[joachim]

a question regarding angle of the implanted hairs:

I don't know how much details you have about the methods from Team Lauster (TU Berlin), but as far I understand they are creating the follicles in vitro, in dishes, where they already develop into hair growing follicles. They use their chip-bioreactor to supply the follicles in dishes with all the necessary nutrients (proteins, oxygen etc.) and it seems they are also able to trigger some signaling so that the follicle start producing hair (please correct me if you have more details about it).
my understanding is that Team Lauster's method is insofar different that the lab-grown follicles could simply be placed on the scalp like a normal FUE, if hair is visible already. There would be no angle problems then, and also the safety/efficacy would be better. You wouldn't implant defect follicles which weren't able to produce hair. only the well developed follicles are used. Maybe the risk then is lower, when they are implanted as fully functional follicle already. They only have to attach to the scalp and blood vessels then and probably won't form cancer-like mutations or cysts. This is a big difference compared to implanting a DP sphere only which has to develop into a hair in the scalp first.

Or am I missing something here?

[Arashi]

Q: Will the treatment/cure you are working on (or any other teams) benefit those who suffer from Diffuse Unpatterned Alopecia? So will it restore a full head of hair to even those who have no terminal hairs?

A:
I'm not sure. The majority of studies use epithelial cells that are very receptive to follicle induction i.e. mouse or human neonatal epithelial cells. We are attempting to use adult human only cells, but this is "healthy" tissue. As far as I know there are no groups using alopecia scalp tissue to test for inductivity. Speculating, I would assume if an inductive enough construct was created that the initial follicle would form. However, as this isn't treating the underlying causes of the various alopecias I would assume the follicle would then degrade as the previously, perhaps even at a faster rate due to the loss of fatty tissue in the scalp.

Q:
Would this not be bound to the same strenuous FDA clinical trials that last another 8+ years? As you know, many of us have been desperate for years and decades to move on with our lives, so we're looking at the fastest possible treatment. Is there some other country whose health ministry is less restricting on use of stem cell therapy in which we could see a treatment that actually holds up to the typical 'within 5 years' claim?

A:
I'm not American or a clinical trials expert so I'm not sure what would have to occur. In the UK if the clinical trial is robust enough then things can pass quite quickly through the MHRA (our equivalent of the FDA). But as I say I'm no clinical trials expert so I can't give you a time frame for that. I was referring to the initial experiment demonstrating the technique appearing without warning.

Q:

How is hair growth direction controlled?

A:
The follicle structures orientate towards the epidermis and do not form cysts. However in the study by Dr Higgins, and my continuation of her work, we are not looking at patterning or angle of egress etc. That's something that will come when we're achieving reliable follicle induction.
agardner is online now Report Post

[hellouser]

Q:

Would you be able to provide a 'dumbed down' explanation of your method of creating functioning follicles for humans? Perhaps in 5 short steps? I'm a graphic artist and will be creating an infographic to inform everyone of past successes, current projects, future treatments, barriers, social prejudice and discrimination against men with baldness and psychological effects on both men and women with hair loss.

[Arashi]

Q:

Would you be able to provide a 'dumbed down' explanation of your method of creating functioning follicles for humans? Perhaps in 5 short steps? I'm a graphic artist and will be creating an infographic to inform everyone of past successes, current projects, future treatments, barriers, social prejudice and discrimination against men with baldness and psychological effects on both men and women with hair loss.

Well that would be something like:
1) Extract patient DP cells from a hair follicle
2) Expand them in an environment similar to the skin, so a 3d environment including patient specific epethelial and DS cells
3) DP Cells will start to aggregate into spheres
4) implant spheres into patient skin
5) spheres will grow a hair follicle

[hellouser]

Well that would be something like:
1) Extract patient DP cells from a hair follicle
2) Expand them in an environment similar to the skin, so a 3d environment including patient specific epethelial and DS cells
3) DP Cells will start to aggregate into spheres
4) implant spheres into patient skin
5) spheres will grow a hair follicle

Thanks Arashi.

Can you (or anyone else) explain how the 3D environment looks like, or what it involves? I'm having a hard time envisioning it.

[joachim]

Question about 3D printing:

There are currently 2 or 3 serious companys working on 3D printed organs with some good breakthroughs already. However, it's still much work to do for creating complete working livers, kidneys including blood vessels etc.
blood vessel printing with the help of some special support material just achieved the first success some weeks ago.

But let's mention one company specialized to cell-by-cell 3D printing:

http://www.organovo.com/

They are really able to print a bunch of different cells in an exact 3D shape using Hydrogel as support material for the cells. Printing cell by cell, accurate and reliable.

so when the key in follicle formation and achieving 100% gene expression is to guide the cells in a way that they mimic the natural form of a follicle to enable the different cells interacting with each other, then why not use Organovo's 3D printer to print all the required cells (DP, epithelial, dermal sheath cup, ...) in the exact shape of a follicle? The process probably only takes a few minutes per follicle, and after that they can interact and bind together (takes some hours probably). The hydrogel dissolves after sometime, I think. At least as proof-of-concept this should really be looked into in detail. Organovo would of course be interested to give their printer the chance to try this out. This could be tested within a few months to have proof-of-concept.

When the 3D printing process turns out to be successful then the printer just have to be extended by multiple nozzles and chambers (reservoires) for the different cells to allow printing of multiple follicles simultaneously.
but first, the proof of concept is important!

And we always hear that the right 3D culturing technique is important (hanging drops, PVA tubes, Matrigel culturing, etc.) but the 3D printer is the easiest way to make a perfectly shaped follicle with different cell types, and the technology is already available.

Maybe the biochip from Team Lauster can be combined with it: first, 3D print the cells, then supply the dishes with further nutrients and proteins so that they have the right signaling to develop a hair.

What do you think? do we have a real chance with 3D printing or is it simply infeasible and we should all forget about 3D printing follicles?
If it's infeasible, what's the reason for it? Has anyone of the hair researches tried it out ever?

[Arashi]

Thanks Arashi.

Can you (or anyone else) explain how the 3D environment looks like, or what it involves? I'm having a hard time envisioning it.

Could be as simple as:



That's from Jahoda.

He decided, instead of growing the papilla cells in the regular petri dish method, he would put droplets of the cells on a dish and flip it over so they were hanging upside down.

Also look here (including pics) https://3dbiomatrix.com/features/

[joachim]

here's a video of Organovo's 3D printing process which can also be found on their website, just to get an idea: https://www.youtube.com/watch?v=s3CiJ26YS_U

[nameless]

* Aaron, thank you for coming here and talking to us.

* Are you saying that when you do manage to encapsulate DP spheres with epithelial cells you get total (100%) preservation of hair inductivity despite mass pass culture?

* I think you're saying is that the problem is getting the epithelial cells to stick to the DP cells. I gather that you're saying that sometimes the epithelial cells do stick to the DP cells but other times they don't. Since sometimes the epithelial cells do stick to the DP cells I'm wondering why you can't simply isolate the method that results in the epithelial cells sticking to the DP cells and only use that method? In other words, since you are able to make the epithelial cells stick to DP cells sometimes then just use the method that results in the epithelial cells sticking to the DP cells and the problem is solved, right?

* When you do get the epithelial cells to stick to the DP cells what do you differently from when epithelial cells don't stick to the DP cells?

* What are you going to try to do to get the epithelial cells to stick to the DP cells? Do you have any ideas?

[joachim]

another scientific question:

how many cells are required to form a follicle? are we talking about hundrets, thousands, millions, or billions?