Interactive Fellows Friday Feature:
Join the conversation by answering Fellows’ weekly questions via Facebook. This week, Nina asks:
If your cells were used to grow an organ in the lab, is it still “your” organ?
Starting Saturday, click here to respond!
What’s your secret to growing healthy cells outside the human body?
It’s an amazing thing that these cells actually grow outside the body. But if we’re going to make them thrive, we need to do a better job of making the cells feel like they’re in their natural environment. That’s one of my main responsibilities — developing systems that we call “bioreactors” that mimic their environment. The cells are really doing everything; we’re just giving them the right environment. It’s like building them a little home where they’re happy.
Once you have the cells and the scaffolding in the bioreactor, you add the “schmutz:” food and chemicals that the cells need.
Then, at our lab we do something unique: we combine all those things with what we call “biophysical cues.” Biophysical cues, such as mechanical forces for the bones and electrical signals for the heart, for the most part have been ignored by biologists and people who study cells. But biophysical cues are really important because the ideal “home” is going to be different for every kind of cell. Bones in the body, for example, experience a lot of mechanical stress. Those bone cells actually need that mechanical stress in order to be happy. To build a bioreactor for bone cells, you’ll probably want to copy that, and you’ll want to provide scaffolding that mimics what the cells would grow on in the body — probably something hard. To build a bioreactor for heart cells, the scaffolding would probably be something soft, like collagen, that is elastic and can bend and beat.
For which cells are electrical signals most significant?
The three main places that I’ve looked for inspiration in terms of electric fields are in early development, the adult lifetime of the heart, and wound healing. Embryos have tons of electric fields, and they’ve been implicated in getting cells to migrate and transform themselves from “undifferentiated” stem cells into more specialized cells like neurons, bone cells, muscle cells, etc. These currents are really important for getting the cells to move around the embryo. Some of the migration is thought to be caused by electrical fields. A colleague of ours has reversed electrical fields and gotten the heart to beat on the right instead of the left.
In development and during an adult lifetime in the heart, we look for inspiration from the EKG and electro-mechanical coupling. That’s sort of what the field has focused on up until now.
Wound healing is also really interesting. Our bodies are full of salt water, and anytime a cell is cut — like in an injury — those salts spill out. Those are charged particles that are moving, which means it’s a current. So any time you have a cut, there’s an electrical field associated with that wound. Those electrical fields have been measured, and we know they decline with age. It’s a cutting-edge topic in regenerative and aesthetic medicine; people are working on how to stimulate wound healing through application of currents.
These are the three main sources of inspiration for my work. And each of these types of signals is going to require different types of bioreactors. Each of those technologies is going to look really different. I call them “enabling technologies” because it’s really the cells that do the work.
What types of technologies are taking your work the next step?
Microtechnology, for one. We’re miniaturizing electrodes. Instead of having a piece of carbon rod that’s 3 mm thick, we work on scaling that down. We think, “How do we make a micro technology that mimics that?” We’ve started patterning electrodes onto glass using lasers. We can grow cells on them, and we can stimulate single cells.
We have much more control over experiments at a microscale than we do at a macroscale. For example, if you want to create natural flow for fluids on a microscale, you don’t have to have turbulence. In a river at the submilimeter scale the flow is perfect. It’s calm, you don’t need any turbulence in order to get it to flow, and fluids, when side-by-side, do not necessarily mix, except by diffusion. That means we can control concentrations both in time and space very precisely!
And it’s really amazing what we can use off the shelf in terms of technology. One of my students has been building an app for a smartphone so we can control our bioreactors from our phones, instead of having to build a controller from scratch!
So what’s the big, hairy dream behind all this?
To get rid of heart disease. The really hairy goal is not just to grow a heart, but that sort of “fountain of youth” element of being able to extend our lives.
Right now heart disease kills more people than all cancer combined. I’d love to see that change.
Have you experienced any controversy from your experiments based on animals and stems cells?
No, I haven’t, actually, at least not personally (we’ve all felt the effects of the changing political environment, though). I am vegetarian, and at restaurants people will say, “Will you get freaked out if I order a steak?” And I say, “No, there’s a karma footprint that each person has.” I choose not to eat meat, but do choose to engage in experiments that involve the sacrifice of animals. I put those things on the same spectrum.
But one thing that I will say is that, in my experience, everyone who’s involved in these experiments has always been very thoughtful, and there are a lot of controls that are in place before you can ever get anywhere near an animal. I think that those controls are really good. They involve members of the lay community — not just researchers and clinicians.
I just sort of hope that when judgment day comes, that, having led a thoughtful life, and having tried to make up for the damage that I’ve done to life and the earth, that I will be judged fairly. But I try to live by my conscience, and I try to see all actions and choices we make — not just scientific research — as sort of the same package. So far I feel OK with where I am on the spectrum, but it’s something I constantly revisit.
You’ve said your TED Fellowship has been incredible for you, and even led to a potential book deal. Have you had any interesting collaborations with other Fellows?
Suzanne Lee is growing clothing out of bacteria. We were talking and wondered, “What if we applied electrical stimulation? Would we be able to get the cells to align?” And Lucianne Walkowicz and I are collaborating on a science summer camp project for girls in India, slated for Summer 2013.
All the Fellows form this amazing community. They’re so cool and so nice!
There are many aspiring social entrepreneurs out there who are trying to take their passion and ideas to the next level. What is one piece of advice you would give to them based on your own experiences and successes? Learn more about how to become a great social entrepreneur from all of the TED Fellows on the Case Foundation’s Social Citizens blog.
Work your idea into every conversation you have, because you never know who can help. A project some of my colleagues and I are working on is a girls’ science summer camp in India. In my experience, you may even have to end up turning people down, because people get so excited about what you’re doing. Keep it on the surface.
The other piece of advice is kind of the same: live your mission. Be on your best behavior. If you believe in goodness, then live goodness. And when you’re talking about your good project, it will be authentic.
Do you really have a double life as an assassin?
[Laughs] I’m involved in the shadow government of Street Wars. It’s a three-week long, immersive water gun tournament. My name in Street Wars is “The Duchess.” And I’m a very accomplished assassin as well as bodyguard. We’ve played across the world, and it’s so much fun.
Street Wars started as a reaction to 9/11. A lot of us wondered, “What’s happened to our city? It’s not fun anymore. It used to be such a playground. Now it just seems like a tomb.” We were all so afraid …. We just really wanted to reclaim the city as a playground. That’s where it started. I think it was really successful in that respect.