Q&A: Grow your own bones to heal without a graft

Could lab-grown bones replace grafts and painful multiple surgeries? Nina Tandon is the CEO and co-founder of EpiBone, a Brooklyn-based biotech company that was chosen as one of the World Economic Forum's 2015 Technology Pioneers. Tandon is also a Young Global Leader. For our XxXX interview series, which profiles 10 inspiring women in science and technology, she talked to us about the body's power to heal itself.

What do you do?

We grow bones from stem cells to hopefully help people who need skeletal reconstruction.

How do you do that?

We take two things from the patient. One is a sample of their fat tissue, from which we extract stem cells. The other is a CT scan, which is like a three-dimensional X-ray of the bone we want to engineer. We use this to make the perfect shape, what we call a scaffold. This scaffold can be made out of protein and collagen from animal bones, or it can be made from synthetic materials. We infuse the cells into this puzzle-piece shape, this scaffold, and over about three weeks the cells mature into a piece of bone that's ready for implantation.

What's the advantage over conventional bone transplants or synthetic transplants?

The current gold standard for reconstructive procedures is called autograft, where we cut a piece of bone out of one part of the body and put it in another. That works quite well for where you need the bone, but it can cause other problems, because there's no piece of bone that's not really necessary in the body. For example, my fiancé had surgery to reconstruct his ankle. They took a piece of his hip bone, and his abdomen even now hurts as much as his ankle does.

Synthetic implants only last a certain amount of time, and people are living longer and longer. If you get injured at 15 and live to 115, the idea that your implant only lasts 10-15 years is becoming unsustainable. So we need new solutions for skeletal repair.

We're also hoping that with our approach there won't be any need for immuno-suppressant drugs because there would be a recognition that it's the body's own, since it's your own DNA.

How far along are you with your research?

We're currently doing animal experiments, and we think we're about 18 months away from human trials.

In terms of taking this to the market, we're looking at 2022 or 2023. This is not a sprint, it's a marathon. You can reprogramme a chip and immediately it takes on a different behaviour, but it takes three weeks to grow a bone. Our technology is moving quickly, but the cells themselves can't be rushed, and medical research can't be rushed.

We've made friends with a lot of surgeons over the years, and they're in desperate need of things like this. They have patients that they want to treat, we get emails every day from people who want to volunteer. But first we need to make sure it's all safe.

Who will benefit from this?

Right now we're focusing on bones above the neck, for cancer, trauma, congenital defects and dental surgery. In this area, about 100,000 procedures are performed every year in the US alone. After blood, bone is the most transplanted tissue.

Could you grow bigger bones, too?

In theory, yes, but the materials of our scaffolds dictate some of our limitations. So we are closely watching any progress in material science that implies we can grow bigger, stronger bones.

How about growing a whole leg, or an arm?

We can all see a future in which our approach can be used for regenerating a whole limb, but that will be much further along because there are many tissues that go into a limb. There's skin, neurons, muscle, bone, tendons, ligaments, and you grow all of those things in different micro-environments. The state of the art right now is to grow two kinds of tissue together - bone and cartilage, or muscle and nerve - and that's already hard. But we're hoping to lay the groundwork for this future technology.

What are your other challenges?

Our main challenge is translating the work from the lab into the clinic, into humans. We have to keep our heads down and do a really good job with the science, so we can get to the clinic and help people.

And what are your long-term goals?

I'd like to be able to say that if you're born with congenital defects, you don't have to be consigned to a lifetime of disfigurement, that you can have your face restored. More broadly, I love the idea that we can look at our own body as a source of healing, as opposed to pills and machines.

In a way it's an agricultural and ecological view of the body, combined with 3D fabrication. It's so old that it's new. This idea that we can cultivate natural systems has its roots in pre-history, with the domestication of animals. But it's being re-envisioned now as: can we repair our bodies using our own cells?

You originally trained as an electrical engineer. How did you move from programming chips to growing bones?

In the early 2000s, I was working in telecoms and I started taking a physiology class at night in the local community college. Reading about DNA and realising that it was much more powerful than a binary storage device, that was a strong analogy for me. I ended up going to MIT to study neural interfaces. I helped spin EpiBone out of my PhD supervisor's lab together with another post-doc, Sarindr Bhumiratana - I was growing cardiac and neural tissue, and he was growing bone and cartilage. So this is certainly a team effort.

As someone who is passionate about science, how would you encourage more women to enter the STEM fields?

As little kids, we are all into science, but then we have to narrow our studies in our teen years. That's when we start to lose our girls, but also many boys, so let's make sure we find ways for them to stay engaged. Toys are a great gateway, and there are some brilliant innovators in that field, like Ayah Bdeir of littleBits, and Debbie Sterling of GoldieBlox. Remembering that learning is about play, and careers can also be about play, all those are ways of making sure we have a diverse set of contributors.

Interview by Sophie Hardach

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