TOPICS > Health

Doctor Discusses the Tissue Engineered Duplicate Organs

October 11, 2006 at 6:05 PM EDT

SUSAN DENTZER: What is tissue engineering?

DR. ANTHONY ATALA: Tissue engineering is actually a science that attempts to bring cells with materials together and by taking cells and place them among materials, the cells can actually be accelerated into growing into tissues that can then be implanted back into the patient.

SUSAN DENTZER: And that’s exactly what you did with the human bladder. Tell us what you did.

DR. ATALA: We found several tissues in the laboratory and some we have been able to transfer into patients, the bladder being one of them. Basically the concept is we take a very small piece of the diseased organ, and we then take that piece of tissue and grow the cell types separately in the laboratory. We then place the cells on a three dimensional scaffold in the shape of the tissue or organ. We place that in incubator for about two weeks and then we’re able to implant the partially made tissue back into the body, allowing the body to finalize the process.

SUSAN DENTZER: And this scaffolding is what exactly?

DR. ATALA: They’re basically just materials that once in the body, disintegrate or go away once the tissue is able to grow and take over.

SUSAN DENTZER: And you’ve done this successfully with the bladder and now have more than five years of data to rely on. What other tissues are you working on?

DR. ATALA: We are currently working on a variety of tissues including blood vessels, heart valves, tissues for other type of regeneration that includes muscle and cartilage, pancreatic tissue.

SUSAN DENTZER: How far along are you on these other tissues?

DR. ATALA: They’re at different levels of development. Some have already made it to the clinical experience. Some are still in the pre-clinical stage and some are still at the very basic level.

SUSAN DENTZER: And by the clinical stage, you mean actually having been implanted back into patients.

DR. ATALA: That’s right. We have implanted some tissues back into patients and we are still under trials under those tissues. There are still some improvements need to be made and there’s still a lot that needs to be done before we’re able to disseminate these technologies widely.

Rebuilding human faces

SUSAN DENTZER: How applicable is this strategy to rebuilding a human face?

DR. ATALA:A human face is a very complex problem in terms of regenerating mainly because there are so many nerves and muscles that are able to promote the facial expression that you have. So it's not just a basic concept of creating tissue that you can use functionally or cosmetically, it also has to be tissue that reacts with you and one does not realize the importance that expression has in daily life.

SUSAN DENTZER: Give me an example.

DR. ATALA: For example, a lot of what we do socially is to interact with each other and we read each other's cues to see how to respond and to how to go to the next level of communication. So a simple smile, a simple frown, those things are very, very hard to reproduce if you're trying to reconstruct something as complex as a face.

SUSAN DENTZER: And you use the phrase a simple smile, but we know it's not really simple to smile. Walk us through what, what the face has to do to smile.

DR. ATALA: Just to create a simple smile, there's a series of literally hundreds of muscle fibers all around the face that have to react in a coordinated manner, all being controlled by different sets of nerves that come together and this contraction of muscles, there's relaxation of muscles and not just of the mouth alone, but the smile actually impacts the whole face so the simple expression of a smile is in reality a very complex set of processes that need to go on in your body.

SUSAN DENTZER: So is it possible to rebuild that, to regenerate that?

DR. ATALA: In terms of regenerating a face, we have to start at the very basic level: How can we just start to reconstruct specific pieces of tissue that will be able to help us bridge the problem. If somebody has a facial injury and they don't have a nose for example, then just a very simple fact of creating a tissue structure composed of foreign cartilage and skin and muscle that goes on to reproduce what normally should be there in terms of just using those tissues without expression, is a very complex process.

SUSAN DENTZER: So this is not trying to create a new face that could smile, a new nose that could twitch, but just get something up there that looks like a nose. You're saying even that is a, is an arduous task.

DR. ATALA: The first challenge is in facial reconstruction is just to bring the structures there and to make sure that you can reconstruct structures that are currently missing due to facial injuries. Once you are able to reconstruct those structures, the next level of complexity is to give those structures the functionality that it actually needs and they're both equally important.

Re-growing cells

SUSAN DENTZER: So let's take the first part, rebuilding the structure. Could you regrow a nose?

DR. ATALA: Today, in 2006, using tissue engineering techniques we still cannot regrow a nose. However, the science is getting to the level where we can regrow pieces of cartilage, pieces of bone, pieces of muscle and bringing these things together all these tissue types together into a coordinated functional organ, that is really the next task.

SUSAN DENTZER: And what would it take to accomplish that?

DR. ATALA: You know one of the major challenges today in the field of regenerative medicine is the resources that we have available to really bring these technologies together. It takes enormous amounts of, of uh, funds to actually get these tissues to look and act normally and that is just in a laboratory. It takes yet another large investment to be able to bring these tissues on the bench to the bedside.

SUSAN DENTZER: So some kind of massive infusion of funding, lots of lab work, lots of scientists working together over a decade? You could actually get to the point that you could reestablish a nose?

DR. ATALA: One of the major challenges that we have in this field is to make sure that we can bring some scientists together, the world experts all together working on common problems that we can solve in an accelerated manner. But to do that you don't just need the scientists who are willing to do it, but you also need the funds to make it happen.

SUSAN DENTZER: DARPA held a workshop where many people, including you, were brought together from various fields to do just that, kind of "blue sky" about what could be accomplished. What was the consensus among scientists? What did they say they thought could be done?

DR. ATALA: In scientific forums, locally, regionally, nationally, and internationally, scientists do agree that these technologies are feasible if we're able to bring our efforts together and if we're able to put the resources that need to go towards that research. I think the possibility of creating structures that are engineered for facial reconstruction is real.

Federal funding

SUSAN DENTZER: You already have some federal funding to look at a different aspect of tissue engineering that could be applicable to wounded armed forces personnel. Let's talk about that.

DR. ATALA: We do have currently a grant from the federal government which is dedicated to limb regeneration and skin injuries. And mainly that research is being done to make sure that we can try to solve some of the problems that we face daily with injuries. As you know extremity injuries are very common. And skin burns are very common. And currently the challenges are to be able to regenerate these tissues in a way that will be functional. So again it goes back to the same challenge regardless of the tissue you're talking about.

SUSAN DENTZER: And how far along are you in that work?

DR. ATALA: The work that is being funded by the federal government in the area of limb regeneration and skin injury is just starting at our institute, the Wake Forest Institute for Regenerative Medicine. This is mainly because the funds take a whole year to actually be processed and we will actually just be receiving those funds in about a month or two.

SUSAN DENTZER: Should there be a "Virtual Face" project funded by DARPA?

DR. ATALA:I think that there should be a massive regenerative medicine project, a nationwide effort to really try to accelerate these technologies to patients. The issue at hand right now is that the technologies are there. We already know that the potential is there. All we really need to bring these technologies faster to reality is a concerted national effort to be able to invest in these technologies that we know have a high potential of benefiting patients throughout the world.

The ability to put muscles and nerves together is a reality today. There are already many examples of them in the field of regenerative medicine. So really it would not take that much more to try to be able to coordinate many muscles together with innovation. It's a complex process but if one again puts a, the scientific rigor behind it and the effort behind it, I think that one could be successful.

SUSAN DENTZER: So to take a case like our patient, Jeffrey Mittman -- you haven't met him but I've described him to you -- in the future, you could actually take a piece of his skin, regrow that skin, regrow the nerves, but it back on his face and have it smile again with the same nerve-ennervating capacities that existed in his face before he was injured?

DR. ATALA: Well that's going to be a major challenge to do that short term. I think it's literally in many, many years before we can achieve that. Initially the goal will be to create very small tissue parts that can be used to replace the areas which have been damaged and then to allow those areas to be incorporated and then to add the functionality to these tissues.

SUSAN DENTZER: So you'd start by regrowing a piece of his, of the bone of his face.

DR. ATALA: That is correct. We, we would first start by growing a piece of bone for his face, and then a piece of muscle for his face, and then skin for that particular area, and then we'd just really build upon the whole construct one step at a time. And in reality, it's not the end goal. The end goal is not to create these structures one piece at a time. The end goal is to create these structures in concert with each other so you can achieve the true functionality that's needed for facial expression.

Different options

SUSAN DENTZER: Now some skeptics say it's really more realistic to think about a kind of prosthetic face, robotic face, such as David Hanson is developing. Others say let's look at face transplants. We've had one successful one in France; some say, let's go that route. Do you think those are more viable strategies in the short term?

DR. ATALA: I think the areas of robotics like Hansen's work and the area of facial transplants like we have just seen recently and regenerative medicine really are all totally complementary because you could actually gain strength from all of these three different areas. And that these areas are brought together you can actually have a much higher success.

SUSAN DENTZER: So give us an example of how that would work.

DR. ATALA: For example, let's say that you're trying to create a new face for an injured individual. You can use a facial transplant to do so, but then you may be wanting to create more functionality by adding nerves to the area. Or more cells to the specific cell type and that's where regenerative medicine could come in. And then the facial expression that you are actually trying to achieve could be actually simulated both before and after surgery using some of the robotic techniques that are currently uh being used.

SUSAN DENTZER: So you can meld all of this together, and achieve a better result.

DR. ATALA: There is no question that bringing these sciences together such as robotics and facial transplantation and regenerative medicine, tissue transplants, all these technologies coming together at the end of the day would yield the higher rate of success in getting to where we need to be.

SUSAN DENTZER: Some have said to me that the plight of these very seriously wounded individuals should rouse us to do something for them - and by extension, that anything we do for them would have enormous applications to the civilian community. Is that a view that you share?

DR. ATALA: I'm a surgeon by training so we see injuries all the time. Any injury's a bad injury. And it is just devastating, not just to the patient, who of course has to deal with these injuries from day one, but also the families and their loved ones. It's a major challenge and I think that anything we can do as a scientific community, as a medical community, as a nation to be able to help these injured patients, to me is in reality what we're all about and what we should be doing in terms of generating the support to get that done.

SUSAN DENTZER: Is there something in your view, especially devastating about losing one's face? Say what you believe.

DR. ATALA: You know, as physicians you know we are facing injuries day after day. A child who develops diabetes, a person who's in a motor vehicle accident loses a limb. An injury from a shotgun wound. Every diseased state, every illness has a devastating effect on the patient and on the families. Facial injuries are no exception. The added complexity however with a facial injury is that you're really dealing in many ways with who you are. How you interact with people. How you exchange ideas and communications and obviously losing a face is a absolutely devastating thing. And it is not just the ability to function that you're losing, but it's also the ability to interact. And in a way that's what humans are about, interaction. You take that away, you take away a bit of somebody's soul.