Podcast: Step Aside Rogaine, 3D Printed Hair Is Here

In this episode, we discuss the breakthrough in tissue engineering from Rensselaer Polytechnic Institute which enables the creation of skin tissue with functional hair follicles and its benefits to the medical field.

EPISODE NOTES

(1:00) - Scientists 3D-print hair follicles in lab-grown skin

Transcript

What's up, folks? On today's podcast episode, we're talking all about this team from RPI that's using a 3D printer to create flesh, real human flesh, skin with hair that grows out of it. It's kind of crazy, but really interesting. So, let's jump right into it.

I'm Daniel, and I'm Farbod. And this is the NextByte Podcast. Every week, we explore interesting and impactful tech and engineering content from Wevolver.com and deliver it to you in bite sized episodes that are easy to understand, regardless of your background. 

Daniel: What's up, folks? Like we said, we're talking all about the future of fabricating human skin with hair in it. Yeah. Kind of interesting. Imagine if instead of using Rogaine or getting hair plugs, you can use a 3D printer to print out new skin with hair right there in the lab. Scientists from RPI, and we just looked this up, I hope I'm pronouncing it correctly, Rensselaer Polytechnic Institute, are turning this kind of wild idea into reality that can create skin with hair in it, real hair, using a 3D printer, which is kind of wack, but awesome.

Farbod: And what makes it crazier to me is, I would have thought that the drive for this technology would be the aesthetic side, which is there's this huge demand for people that wanna get hair transplants and whatnot, try to see if we can address that market, but no. It turns out that your hair follicles actually have a lot of function for regulating your body's temperature. They're the major receptors for topical ointments and applications of the sort. So, if we could do something like replicating the human skin that actually has functional hair follicles, it would be pretty good for medicine medical development.

Daniel: But obviously, the aesthetic portion isn't trivial. It's not right.

Farbod: It's not, not at all.

Daniel: One of the things that I think of obviously outside of like I think, all my social media knows that I'm a male. So even though I still luckily have a full head of hair, I've been inundated by ads saying like, take this medicine to preserve your hairline or go to this doctor to get hair plugs or travel Turkey to get hair plugs, right? Like, obviously it's all kind of crazy and I feel like that's like kind of what makes this topic.

Farbod: Stop wearing hats.

Daniel: Yeah, top, I don't know, wearing a hat. Makes this topic kind of buzzier. Like get a certain shower head that helps filter out chemicals so you don't lose hair, et cetera. That's a big deal, obviously for an aesthetic purpose. But I also think about folks like burn victims. If their burn is severe enough and it damages the hair follicles, the hair doesn't grow back properly. So, in addition to men with male pattern baldness, they want to reestablish their hairlines, et cetera. Right. There's a real medical purpose for this as well. It's like, lots of folks, and actually this is where this team got started, is developing skin grafts for burn victims. They're now being, they're one of the first teams that are able to really fabricate skin from the ground up that have like real vascular patterns in it. So, they started by 3D printing skin and veins, and the veins function properly, and now they're one of the first teams to do it with real functioning hair follicles as well.

Farbod: I think if I'm not mistaken, this specific team was the first to do it with the veins that are actually functional within a skin graft. So that's what makes them so impressive here. They're the trailblazers when it comes to artificial tissue slash skin development. Now I guess it's worth talking about their previous researchers, how do they tackle the skin development. Well, they use this like very popular approach of 3D printing using bioink. We've talked about Bioink at least a dozen times, I feel like by now on this podcast. We've talked about Bioink for tissue engineering. We talked about it for creating a heart replica that has a functional valve.

Daniel: We've even talked about it for 3D printing bones as well.

Farbod: Exactly. So, what they've done here is that they create a culture of skin cells and then they mix it with the necessary proteins and whatever to make sure that it's able to sustain and grow. And then layer by layer, they create the skin from the ground up just as, that's the main benefit of additive manufacturing is that you get to architect the entire geometry.

Daniel: You choose the geometry, right? Exactly. They use this, they call it ink, but I think that's a little bit misleading because in my mind, at least as a layperson, ink sends me to think like, oh, it's a liquid. It's actually a gel and if they treat it very carefully, they can print in these patterns and it holds the microstructure that they want. So, think of it kind of like a more like Jell-O, let's say coming out of a nozzle. They mix, like you said, a culture of skin cells or I think parasite cells were the ones and not pericyte, like something leeching off of you, parasite, P-E-R-I-C-Y-T-E, pericyte cells, those help form the vein structure. So, they specialize to like, this is vein tissue, this is skin tissue, and in the future they're gonna, they worked on like, this is hair follicle cells, they mix it with animal collagen, which kind of makes it like that jelly texture. And then they're able to 3D print it out of a nozzle using the shape that they want. And obviously like we were talking about in their previous research, they were able to get cells that specialized and then continued to grow into a like 3D printed skin tissue that was living, breathing, functioning, using skin cells and then obviously the vascular cells to make blood vessels. So, they were able to create real skin with blood vessels that circulate, that could circulate blood into that skin tissue. But like you mentioned, at least in terms of drug development for topical ointments and for treatment of skin conditions, they use these like fabricated or 3D printed tissues for testing. But these traditional skin models completely lack the complexity with hair follicles. And like you said, hair follicles are the main gateway, let's say, by which topical drugs can enter the bloodstream. So, it's like, how am I gonna develop a topical drug? How am I gonna test it in a laboratory setting if I haven't even included the geometry of the major port way into the body? So, this team kind of stepped it up a notch. They say, all right, we can already do skin. We can already do the vascular skin with blood vessels. Let's try and also implement one of the most important structures in the geometry of the skin, which is the hair follicle as well.

Farbod: Yeah, and I feel like prior to having access to this type of resource, where you can mimic the human skin and the human skin with the hair follicles, you just had to kind of resort to animal testing. And we can see both in the medical sector and the beauty sector, I guess, the beauty industry, where you got a lot of makeup companies moving away from manual testing people are just not okay with that anymore.

Daniel: For ethical reasons.

Farbod: Yeah, of course, and it totally makes sense. So, we need to have alternatives that still allow us to test these drugs and make sure they're safe for human use.

Daniel: Yeah, well, absolutely. I don't want there to be inhumane testing of a certain ointment that I'm gonna use on my skin on animals, right? But I also don't wanna put some dangerous ointment on my skin that hasn't been tested. So, like you're saying, we have to find a new solution here and it sounds like this team from RPI might have found a way forward.

Farbod: Yeah, and well let's talk about their sauce. How do they do it, right? The genius is still within this additive manufacturing approach, right? They are bringing forward the work they did to create the skin tissue. And just as you had mentioned, we're going layer by layer. Well, within these layers, you can actually create channels. You have full control of the geometry, so you can create channels where you deposit these specific hair cells and over time as, what's the right word here, as it cures, I guess, as the tissue is, the cells are combining and becoming the tissue, what they've started to realize is that these skin cells and hair cells go through a process of self-assembly and create that bulbous shape where you would expect, that the hair follicle would form. Now, so far, these tissues don't last more than two or three weeks, so they haven't been able to see hair grow. That's just not enough time for hair to grow. But the assumption here is that if given more time, you would start seeing hair come out of those bulbous empty holes.

Daniel: If you've never seen what the cross section of a hair follicle looks like, you should check out this article or go Google it on Google. Go check it out see what it looks like. You're saying bulbous, it looks like you took a cross section of an onion and buried it in the skin, right? This is at the super microscopic level. It's just a big bulb under the skin and it produces the keratin protein that grows out his hair. And obviously, like we said, it's got all these other relations to sweat and oil glands. It's got relations to getting topical ointments into your bloodstream, doing thermal regulation to the body. So, there's a lot that goes into the hair follicle, but pretty encouraging that they're able to print in this geometry, right? To mimic the hair follicle geometry and then watch those cells in the bio-ink grow and start to specialize in the way that they intended them to. Obviously, like you said, the lifespan of these tissues are pretty limited. I think that there's probably a couple next steps for their work that bridge off of this. One of those being, let's try and make sure that we can extend the lifespan of these tissues for the laboratory and drug testing scenario, right? If you wanna like effectively test whether these tissues can grow hair and like be a true surrogate for testing on human skin, you're gonna need it to grow longer or to live longer so that it can grow hair and be a true accurate analogy for testing on the human body. I would say the second avenue that they wanna explore here is maybe they're able to extend the lifespan to a couple of months in the lab. Also trying to understand what it looks like to transplant that, use it as a skin graft that can actually grow hair onto burn victims. A lot of the artificially manufactured skin grafts right now aren't, they aren't able to grow hair. And they, one of the things that the lead researchers mentioned is a lot of those artificially manufactured skin grafts aren't even real skin grafts. They're, they're a lot more like a really, really advanced, really fancy band aid. So, this is something interesting. They're using a 3D printer to manufacture real living tissue with real living cells. It starts as cells suspended in this gel and then it grows into real tissue over a period of time. They can not only make skin with blood vessels in it, they can also create these channels with cells that eventually specialize and become hair follicles, which is really interesting as well.

Farbod: For sure. Another thing that I'm wondering is a potential unintended consequence of doing this work is now that we're taking on, we're mimicking what we're composed of, we're essentially creating skin from the ground up. And the purpose of it is, just like you mentioned already, either using it as a graft or doing medical research to make sure the things that we're creating to put on ourselves are actually safe. I'm wondering if an unintended consequence of all this is us better understanding how hair cells and hair follicles and skin in general operates because now we have this repeatable perfect test scenario that we can experiment on over and over and over again and increase our existing understanding of how, you know, I didn't know how important the hair follicle was until I read this. So now I'm curious, like will we learn more about it through these trials and whatnot?

Daniel: Well, and obviously I'm excited, like you're saying, with a better understanding of how this manufacturing tissue, in this case skin, right, with the complex systems that are involved involving the hair follicles and all the other subsystems of the body that that impacts. I wonder if this also unlocks some level of understanding for creating other sorts of complex tissues in the body as well. It's an interesting trend that we've talked about multiple times on the podcast, right, that there's an interest in being able to manufacture tissue in a laboratory setting, whether it be for drug testing or whether it be for implantation into a patient. This seems like a huge breakthrough here where they've really started to, at least from my perception, start to crack the code on using engineering and manufacturing to create tissue. So, it's like bridging the gap between these hard disciplines in engineering and then the medical life sciences domain. It feels like they've started to bridge that gap.

Farbod: Yeah, it's super exciting. Do you think, you know, taking a step out of the details of this article, just from a high level, how far away do you think we are from achieving skin grafts with functional hair follicles? Do you think we'll see it in the next 10 years or so?

Daniel: I'd like to think so, especially in the context of like growing hair or creating skin grafts that can grow hair for burn victims. I feel sincerely for folks who are burn victims. I think about my brother all the time because he's a firefighter. Like if he were ever involved in an accident, he got burned. Like it would be really, really sad if he wasn't able to grow hair. You know, once that burn healed and he wasn't able to grow hair on his head or something like that, right? Obviously skin grafts are already used as a method of treatment for that. It would be awesome if those skin grafts could also produce hair in a way that like he could feel comfortably aesthetically with his head. That being said, I don't think we'll see it in an aesthetic scenario. Like it doesn't make sense to me, at least in this case, like as a replacement for hair transplant because you're not just implanting hair follicles into the head. This is truly fully engineering tissue. This is like saying like, if I was bald, you have to scalp me and then implant this new 30 printed skin grafts to be able to grow hair, but I don't know. Maybe they're able to 3D print just the follicle and implant those. That'd be interesting as opposed to, I'm not even sure truly how…

Farbod: Isolating it.

Daniel: I'm not sure truly how hair transplant surgery works. I haven't looked into that much, but I imagine they're pulling hair follicles that are working from some other part of your body and then implanting them into your head. That creates two surgery sites. Maybe this creates only one. I'm not sure. Definitely a little interesting. And I don't know, obviously it's a little bit buzzy. We talked about like mostly joking here, like stop using Rogaine, don't use hair plugs, but there's a true clinical usage for creating skin grafts with hair, hair that can grow. And then obviously I'm super interested to see if there are additional breakthroughs in the development rate of like treatment for skin conditions and stuff like that. Now that they're able to use in a low-risk scenario, right? Using a laboratory surrogate for skin laboratory engineered tissue rather than testing on real skin or testing on animals to try and develop drugs faster related to skin conditions and other topical developments and stuff like that.

Farbod: Yeah. I mean, as you can probably tell by the way I've talked about this episode, I'm pretty like cautiously optimistic that we'll see this technology be used for development of new drugs, like at least within the next 10 years, but maybe even at the tail end of it, hopefully we'll be able to see skin grafts for in medical applications for burn victims. That would be awesome. I do not see this being used for like aesthetic purposes anytime soon. Just like you said, there's still a couple more barriers to get through, but interesting ideas you threw out there. I don't know, maybe it's possible. With that said, I think you should wrap up and give us a quick TLDR rundown of what's going on here.

Daniel: Yeah, for sure, man. So, like we said, this whole team, it's a team of engineers who've put their heads together to try and understand how they can print new hair or new skin with hair, right in the lab using a 3D printer. They start by using real skin cells, real vascular cells, which are for veins and blood vessels and real hair follicle cells. They grow them in a petri dish and then they mix them up to this ink, which is kind of like a Jell-O type material that's printed out of a nozzle using a 3D printer into the desired shape. They allow these cells to grow and it turns from a collection of cells floating in gel into real life flesh with hair and blood vessels that function. Right now, that flesh only lives for about three weeks, but they're doing their best to extend the lifespan of that so we can use it for drug testing and potential implantation for treatment of, you know, stuff like burn victims.

Farbod: Perfect.

Daniel: I will say, before we wrap up this episode, we have to say thank you to the folks in Oman. We are trending there. And as a promise that we made at the beginning of this year, we're gonna learn how to say thank you to each of those people, or to each of the countries where we're trending in their majority of their official language. In Oman, I believe they speak Arabic. So, I want to say “Shukran”. Thank you to the folks in Oman for helping us trend there. Obviously, everyone who's a big part of this community, we appreciate you, but especially the folks that are helping us pop onto their trending charts. That's extra interesting.

Farbod: Yeah, absolutely. Everyone, thank you so much for listening. And as always, we'll catch you in the next one.

Daniel: Peace.

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The Next Byte: We're two engineers on a mission to simplify complex science & technology, making it easy to understand. In each episode of our show, we dive into world-changing tech (such as AI, robotics, 3D printing, IoT, & much more), all while keeping it entertaining & engaging along the way.