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Living skin can be 3D-printed, with blood vessels (rpi.edu)
244 points by EndXA on Nov 2, 2019 | hide | past | favorite | 27 comments



For some perspective on why this matters. If you've never had a serious skin issue it's hard to understand how traumatic it is. I had basal cell carcinoma (a treatable skin cancer) in my early 30's on my nose. The treatment was careful excision of flesh from the affected area. The thing you can't prepare yourself for is how much and how deep the necessary removal is. Imagine a stack of 5 dimes taken out of your nose, and in it's place, a dark and gaping hole.

It is impossible to look at oneself in the mirror without a sense of revulsion and horror. It then takes months of careful wound care for flesh to regrow. My case was simple, and I healed as quickly as could be expected. Most people who need skin grafts are not so lucky.

I sincerely hope this technology is proven effective and makes its way out to the real world as soon as possible.


I have skin grafts on ~30% of my body and donor sites on another large fraction (although not on the face). I’d be pretty excited about skin grafts that actually looked decent.

It’s tricky though, since there is an uncanny valley: if it doesn’t look natural, it might just look inexplicably weird (think mismatched hair). I’ve felt this way about some of the more modern techniques for large full thickness grafts I’ve seen photos of. Partial thickness grafts have the advantage of being unambiguous (but obviously unnatural looking).

Even if it would be possible to “fix” my issues with whatever we develop in the next n years, it definitely won’t be worth redoing it. I wouldn’t wish skin grafts on my worst enemy. Fortunately, I was young enough not to remember the first time around.


I agree that 3d printing is potentially of value for tissue engineering, however in this case the printed tissue is functionally no different from a full thickness skin graft which is used routinely for reconstruction of nasal defects and has significant limitations e.g. inability to reconstruct a deeper defect and colour/texture mismatch.

COI: Mohs surgeon


Ah well :) Good to know, thanks!

Btw, what does "COI" stand for in this context? That's a new one to me.


Conflict of Interest?


It's true that some wounds can tap into important emotional representations. Limbs may be a bit easier to endure.

My first thought is to fire victims..


Boardwalk Empire expanded upon this quite a bit with one of the characters who loses part of his face in the war. That's one part of Television I like.


Does anyone have access to the full text? Sci-hub hasn't got any proxies for this apparently.

I'm curious what geometry they're printing the the EC/PC bio-ink in, eg printing coarse grained vasculature networks.

If they're leaning too heavily on self-assembly I would start to question the term 3D printing here. Particularly if they're, for example, just printing homogeneous layers of the different inks and the syringe-on-a-gantry was just a readily available way to do so.


It’s round and 2cm in diameter when we do in vivo studies in mice. But with the printer we can potentially scale up and make any shape we want. The advantage is that we can create personalized shapes with different thicknesses to fit the wound site. You’re correct: in this study 3D printing is being used as a tool for high throughput production of skin tissue. This will be important to make this a cost-effective treatment. However, we are also working on the inclusion of hair follicles which require patterning and later self-assembly. Microvasculature in skin doesn’t really require patterning but higher caliber vessels in other organs, such as heart, will likely need it.


Email me, check my profile.


> Karande said more work will need to be done to address the challenges associated with burn patients, which include the loss of nerve and vascular endings.

Slightly off-topic, but it may be high time for a Darkman reboot.


Can we keep Liam Neeson?


Would this allow for replacing of scar tissue? Essentially cut out the skin you want to remove and replace it with this? Or does it not quite work like that? Btw when I say scar I'm not talking about a cut line, since the will likely be a noticeable scar like between the new and old skin, I'm referring to larger ones like burn scars. Wondering if this could also be used to replace things like vitiligo patches.


Which organ is closest to being 3D printed for real patients? I've seen articles about 3D printed livers and hearts almost a decade ago.


Bladders have been successfully grown and transplanted into patients.

https://3dprintingindustry.com/news/bladder-grown-from-3d-bi...


The skin is an organ, all kinds of patients need skin grafts as treatment.


Is the final product like... electronic? What is the input material to 3D print this and what is the output?


Input is cultured cells, output is a functional biological structure. In principle it can be anything from a simple part like an earlobe too something complicated like your entire body outside your brain combined, though the latter is very far away at this point.


Why not the brain?


The brain is a 3d structure with immense complexity tightly packed and out of reach of any non-destructive probe, and the details matter. In fact, we don't know yet, to what extent they matter - or for that matter, which details. (Structural obviously. Electrical probably not, as that recovers from erasure. Chemical? Quantum? Answers are guesswork right now.)

The last person I read talking about how to scan a brain in detail was Anders Sandberg and his method would require death, brain removal, slice-n-dice, vitrification, microtoming and staining, and microscope scanning on an enormous parallel gang of microscopes, followed by computer assisted reassembly into a 3d model, and analysis so that neurons and their connections can be mapped.

Now imagine having all that data and trying to reverse it into a connected, living organ. Even if you could place all the cells and their wires that precisely, could you keep them in situ and oxygenated as you're printing billions and billions of individual pieces? And finish it before doomsday? And avoid it suffering the sensations of half-a-brain that is inexplicably not dying as it gradually grows towards sentience, for the duration?


Tongue in cheek: we know of simpler means of producing a person.


We don’t know enough about the brain yet to copy it, but what we do know would require reshaping each neurone to create the right synapses and dendrites and that’s not really 3D printing.

(While it is also notable that bio-printing is currently at the resolution of blobs off cells rather than individual cells, that’s not an in-principle objection in the way that post-processing 3.5nm resolution features into cells which are about 25μm in size is).


I assume you could do the gross structures eventually, but the real original neural state wouldn’t be there so not much point.


According to the article, the input is human cells. Same with other organs - it typically refers to an actual organ as the end result, with maybe an artificial carrier structure etc to shape the cells during growth.


Hi everyone. I’m the first author of this paper. The full text should be available in the “just accepted” section of Tissue Engineering part A. It will come out later in print in a special issue on “3D printing for tissue engineering”. I’ll be happy to answer any questions you might have about it!


What about intestines? I know someone with a ‘permanent’ ileostomy and I’m banking on this kind of technology to let them poop again.


TFA says the grafts were rejected by host by the way.

The progress shown was that the grafts now have a functional-ish vascular system that booted up.

Still a long way to go.




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