Richard Jacobs: Hello. This is Richard Jacobs with the future-tech and future tech health podcast. I Have Jacob Koffler UC San Diego working on a biomimetic 3d printed scaffolds for a spinal cord injury repair. Well Jacob, thank you for coming.

Jacob Koffler: Thank you very much. Thank you for having me.

Richard Jacobs: Yeah. What got you interested in working on a spinal cord repair?

Jacob Koffler: Um, I did my Ph.D. in biomedical engineering. I’m working on muscles, um, vascularized skewed muscles. Towards the end of my phd, I sort of wanted to move into a new field and um, I wanted to be able and contribute, um, my knowledge in the new fields, um, where there’s not a lot of, um, tissue engineering and this kind of research involved. And I learned that in neurology and specifically in spinal cord injury back then talking about 2010, nine years ago. Um, there wasn’t much of this kind of interdisciplinary approach, tissue engineering, scaffolds and so on. Um, and, and on top of the test spinal cord injury, the fieldwork there still, there’s still a big need for treatments because people, for example, cardiovascular research, um, someone goes to the ER with a, with a heart problem, the doctors pretty much know what to do. Um, you know, what drugs to give. The patient has a good chance of going back to the previous life. Um, as before, while with spinal cord injury is still no approved treatment. And so I thought that I would, um, I’m interested to bring my, um, knowledge and, and contribute to fields where there’s a big need that I felt like the, there’s a big need in the field of spinal cord injury. Um, and I, I bet tissue engineering, um, can contribute, um, to develop new treatments.

Richard Jacobs: Right. Okay. With what I know, with the spinal cord, it doesn’t, the nerves won’t regrow, right? If there’s a tear or a disruption, is that right?

Jacob Koffler: Yes, that’s correct. In the central nervous system. If someone is injured, for example, in the car accident and the spinal cord is severed in a way that um, he’s losing function, um, he’s not going to get the function back again. Um, chances are, there are, there is some spontaneous recovery but that’s again spontaneous recovery, Um, it’s not something robust that happens. If someone, um, sitting on a wheelchair or does not have any motor neural function under the injury level, that’s probably going to be there for the rest of his life. Richard Jacobs: What about in the peripheral nervous system? Is there at least some healing there?

Jacob Koffler: Yeah, the peripheral nervous system is different. It does regenerate after injury. Um, it’s a difference in our, you know, there, in terms of treatment, the treatment there, um, what you usually do, the gold standard used to do a nerve grafting, autologous nerve graft. So the, um, the surgeon will take a sample of the nerve usually from um, and then implant that, um, where you need to repair that gap injury. Um, and then, that’s the state of the art. That’s what they are doing. The cleaning, there are some approved clinical devices for short gaps, but they’re perceived as not beneficial. They’re not really improving. Um, the patients live, you don’t regain the, your function, your motor function, your sensory function. It doesn’t get back to what it was before the injury. So really the gold standard is, um, is a nerve graft and Ortho.

Richard Jacobs: Why, why don’t the nervous, especially the central nervous system regrow? Have you looked at the particular cells that would be involved in regrowing and found out anything about them?

Jacob Koffler: So that’s a great question and, and we don’t have a good answer. Um, um, what we know is that the after injury in the central nervous system in the spinal cord, um, there is a clear, I’ll call it, it’s formed around the injury site that is believed to inhibit regeneration. There are some other extracellular matrix components that inhibit regeneration. It is taught that maybe the nerves that themselves, um, has, um, don’t have the program that would then enhance regeneration. I and people are working on different approaches to enhance axon regeneration in the central nervous system using gene therapy, crisper, stem cells. Um, some papers from our lab, um, showed that, um, central nervous system axons can actually regrow if you provide a matrix that would support this regeneration for example stem cells. So, we had a few papers showing that, um, but it’s a little question why the central nervous system acts on its own regenerate. Um, and um, and those, a lot of research, a lot of efforts in this field. And I suppose that once we’ll know, then we’ll be able to discover new mechanisms that we can then change maybe and help regeneration.

Richard Jacobs: Well, the nervous system has stem cells that are native to it like other tissues do?

Jacob Koffler: So yes, in the brain, uh, not so much in the spinal cord. Um, so it’s in the context of spinal cords, you can’t really say there are native stem cells in the spinal cord that can proliferate and then provide a new matrix for regeneration. And it’s not like, for example, in the, in the muscle that you have set the light cells in there, that muscle embedded in the muscle villas are sort of a mature, they’re halfway to mature cell. And when you have an injury, those can’t wake up fully to go into the injury and create new muscles. So that kind of thing doesn’t exist in the, in the spinal cord.

Richard Jacobs: Well, during embryological development, you know, our uh, central nervous system is growing and innovating and all that. And then I guess it, I don’t know, I mean we continue to grow after that. So I would think that our nervous system, the central nervous system grows with us as we grow and lengthen. Yeah. Has anyone studied somehow and juveniles, you know, even juvenile rats, how the nervous system grows over time and you know, what kind of cell to cell communications happening and when that stops or if it stops.

Jacob Koffler: Yeah. So that’s correct. And um, that’s part of the approaches that people are taking and that is to look at development. What happens in development, why young neurons are able to extend long axons, create sign upstairs. And what’s changed in the, in the program, um, of the mature cells that they don’t do that anymore. Why, um, stem cell divide axons, neurons that extend long axons can do that. Um, we’re trying to learn from the stem cell field, um, um, watch young, um, neurons that are developing, differentiating from stem cells, uh, and are able to extend long excellence, what kind of programs they express and how can we use technology to drive the mature neurons in the brain to extend axons again after injury. So yes, definitely people are looking into that, but that’s a big field as you need to dig into the DNA, into the RNA, to the protein, um, um, reservoirs that you have in the industry. All you want to see what is being expressed, why dysfunctioning in the cell. So the slow proteomics and, and, and RMA seek and DNA, um, um, expression studies. And, and as you can imagine, those a lot of bioinformatics, um, that goes into that, you know, there to try and decide for those huge amounts of data that’s coming out of these studies. So yes, there’s a lot of effort in this field to try and learn from development.

Richard Jacobs: Well, what about even the physiology of the spine, the morphology of it as, as, um, the juvenile grows, you know, maybe the spine just doesn’t get longer, but also the nerve bundles, you mean more nerves accumulated or maybe at least somehow radially thickened. I mean, any clues there on how the spine, you know, grows like the one, as a juvenile to see the point at which the spine grows?

Jacob Koffler: Yeah. So the way it’s worked in development is that as an embryo, um, the development period is meaning the time where the nerve extends an Axon and an Axon gets to the appropriate target, um, is really while you’re, um, um, probably in the first try mister and beats longer than that. And as you grow older, you’re talking about elongation of the system. So there are a few, um, closest to that is happening, right? The elongation and there is um, creating the synopsis is um, and those are different processes. Um, and yes, and as we grow the nervous system grows. But the nervous system itself is already there. Um, it takes us up to two years to develop fine motor skills. You know, that we, being bad but most of the fine motor skills or are developed during the first two, three years. Um, and that’s pretty much not a function of new nerves. Innovating is just a function of shaping the connections that are already there. Creating may be new synopsis or new targets, but it’s not so much re-innovation of the whole system you don’t have when you are two years old, um, a new nerve that extends and new axons all the way from the brain down to the spinal cord, those are already there. Those already innovated your, uh, hands for example. Um, what you have now would be just shaping that innovation. Um, so you can really, um, why did you acquire those fine motor skills? The system can adapt, but you don’t have new, new, a new innovation when you’re two years old, it’s not there. So it’s, it really happens. All of that happens early on in time. That’s why we learned from stem cells because stem cells are present that the early population of the neurons. And that’s what we’re trying to learn from how to drive development again in any injured system.

Richard Jacobs: So what, what’s your, uh, your hypothesis, how do you think it could be best done?

Jacob Koffler: So some of the studies being done, I mean is you try to find, um, one of the genes that are being expressed in those stem cells. Now extending Axon’s for example, and then you go to the injured system, the mature injured system, then you want to see those genes are expressed. If they are maybe downregulated, maybe you can upregulate them. Um, so that’s the kind of approach being taken point sample into soon.

Richard Jacobs: Have you tried to look at again, cell by cell communication of the, uh, the edge cells versus the ones that aren’t on the edge that isn’t damaged or internal?

Jacob Koffler: So communication, not sure what your, your, um, once you refer to it, I think you’re different so it’s not a so, so in the spinal cord, what you’re looking at are axons. So if you think about that, the Axon is like a, like an electrical wire. Okay. You have the source of the signal that comes from the brain, from the neuron and then there’s a long process like an electrical wire that goes through the spinal cord. Okay. It’s not a cell body, it’s just the, it’s just the wire itself and when there’s an injury the wire is cut, um, when the wire is cut there are a few things that happen first, but everything that on the other side of the injury, the way from the brain is being degraded. So that part of the wire that’s part of the Axon dies that dies off, you lose that, second, there is some retraction of the part of the axon goes, some retraction of that electrical wire that’s closer to the brain and different systems restructuring differently. But there is um, some extent, um, uh, which faction away from the injury side, not much, but there is some. There is the ugliest car. There is, there is a kind of a car that forms around the injury site and blocks it. The reason is that they, the injury itself easy, very inflamed. Anything that interrupts close to that will die because um, inflammation is just clearing everything there. So there was a lot of the cell debriefed or a lot of junk, there was a lot of liquidity in there over time in humans that would clear and you would just have cavities in there. Well, that’s the mechanical point of view.

Richard Jacobs: So you’re trying to 3d prints, the missing structures with coupling to the existing structures or what’s your methodology?

Jacob Koffler: So, so what we are doing is since all that structure fell down and disappear what we are doing is to provide the structure again. So, uh, and, and we do that in a biomimetic approach. Meaning we’re looking at how the structure was designed previously, what’s the metro architecture of the spinal cord? And then we create a scaffold that looks exactly like that and we bring him back into the lesions. So, so in turn, so we’ve, we’ve printed to, we can print to um, kind of features. So the first is if you would look at the spinal cord in the longitudinal aspect, the size of the injury, there wouldn’t be, there won’t be a clear cut. It’s quite rare. That would be like a clear cut. They would have some Jagger kind of sides. So we can print a scaffold that would look like that. So match the way the contour of the injury would look like. The second feature that we print is that we print Longitudinal Linear Channels. Those channels support regeneration of those hosts axons that we’ve talked about, those electrical wires if able to regenerate into the spinal cord because when axon is regenerate, um, generally they, they venture in all directions and that’s also what happens in development when an Axon elongate, the way it goes into space is to venture in all directions, trying to find which direct way to go in order to get to the target. So axons can go, you know, left, right up, down, even backward sometimes. And so, um, w what we do is when we provide those linear channels, you were strict the growth to one side. So there’s on the other type of the delusion, if an axon gets into a channel, it would go directly to the other side. There’s nowhere else to go. And a previous paper from the lab from 2010 show that, um, if you provide stem, um, just a stale grasp without channels. Um, in an injury site in the spinal cord, only 20% of the axons would reach the other side of the injury. But if you provide channels, more than 80% would reach the other side and that’s just because they’re organizing that regeneration. And the other part, the third part is that we then provide, um, neural stem cells, um, inside those channels. And then what we do is we have another approach where we create a neuronal relay. So when the, there is an injury through the spinal cord, not only those electrical wires being damaged, there is also a local um, population of the neurons that provide some kind of, it’s called that relay, um, processing for signals naturally as they go through the spinal cord. These kinds of these cells, uh, naturally are in what’s called the gray matter of the spinal cord and they also die and they are also damaged in an injury. And so we provide them back inside, uh, um, the channels and then those excellent. We are now able to regenerate into the scaffold because the stem cells provide this permeable matrix. They would meet a stem cell-derived neuron, create the sign-up, and then relay the signal to the stem cell derive neuron. The stem cell derives neuron in now can take the signal extent new Exxon to extend the new electrical wire. That would go down the spinal cord beyond the injury and reconnect to the periphery. And so this way we’re reforming that relay that naturally existed a spinal cord.

Richard Jacobs: Well again, if you’re going to send a nerve, we’ll tend to innovate more. If it has a path, then they can follow, you know, the nerve is the end of the nervous sitting there at the beginning of the path. How is it sensing what’s there is a path and that there’s a, you know, there is a certain path ahead of it. So it should be grown more than not, how could it do that?

Jacob Koffler: So that’s, that’s, we’re not controlling their regeneration pace rate. What we’re calling, what we’re doing is we’re shaping regeneration. And so some systems, so there are multiple systems in the spinal cord. Some of them will be the sorry system. Some of them would be motor systems. Some of them would be in charge of fine movements. Some of them would be in charge of growth motto, Each system, each bundle of electrical wires, each bundle of axon originates from different cells in the brain. And each one we call the track. Each track has a different capacity of your generation. Some of them will not regenerate at all. Some of them, if you provide stem cells, would suddenly wake up and, and regenerate. Um, and, and this part of the thing that we’re trying to understand why they wake up now and that’s what I described before. And so, um, we’re looking to find out what happened. Why, and again, this is a gene expression study, not a scaffold study. The gene expression study where once you were able to admit that regeneration, you want to go back and see what happens, what genes are expressed, what genes are upward related, what genes are downregulated, and then find out how you can maybe improve that. What can you do to more regeneration? Um, and that’s ongoing studies.

Richard Jacobs: Do you know things than waking up process that has to do with the cell, that particular cell somehow taking in information that now it has a path before it? Yeah, I think you should grow into that path.

Jacob Koffler: Yes. I definitely agree. Yeah. Because without that, we don’t, without the stem cells, we don’t see a significant regeneration. So definitely the stem cells provide, Um, And, so, and that’s a big question. So what are they really providing? Are they’re providing just a more supportive matrix? Um, are they providing some kind of chemical cues? Are the chemical cues local? Are they, uh, being, um, transfer, communicate and longer in terms of a length away from dangerous science. These are ongoing studies too. Find out the mechanism of regeneration.

Richard Jacobs: So what specific area are you focusing on? Uh, making sure that the pathways are optimal or what’s your role?

Jacob Koffler: Correct. So I’m focusing on, on printing and stem cells regeneration, um, and um, focused on providing, um, the best structure that and first, um, um, help shape regeneration, support regeneration, guide regeneration too, uh, to the target. Because even if you put just themselves, let’s assume for example now that the stem cells are the best thing we have, stem cells by themselves when they extend their Axon, they go in all directions. So again, even the stem cell themselves need guidance. So, um, providing guidance to host regenerate, Axon and stem cells derived Axon, um, we’re adding the stem cells. Again, that’s another approach, um, to, um, provide new role and on a relay that would able, um, to create super spinal controls, a significant, hopefully, significant a control. And over the periphery. Um, we also provide, um, a matrix of the scaffold itself that would able to provide a protective environment to those stem cells because part of the thing that we showed was that, um, we were able to, um, provide a protective environment in an acute implant, meaning and injured spinal cord that had an immediate treatment, immediate implant with scaffold and stem cells. Um, if you compare that to just themselves, um, the stem cells do not survive when you implant the stem cells in the acute time. Um, while we have that, um, inflammation that we talked about before extensive inflammation, that extensive inflammation is toxic to the cell, the cells die. That’s why any other stem cell studies that been so far all in the subacute, one-week post-injury, two weeks post-injury implants, not in the acute implant, uh, not in the acute time frame. And so what we showed was that using the stem cells, um, providing that protective environment, it opens a new window for treatment in the acute time frame, which is relevant because what happens with patients when they get, um, to the hospital in the first three to four days, they would go already through the first, uh, at least one surgery. Um, it’s called debridement, the so it to clean all the um, all the junk that’s in the spinal cord due to the injury and maybe reduce, um, um, bone, uh, compression. Usually, there is some kind of piece of a bone that creates pressure on the spinal cord because there wasn’t an injury. So you need to go in and relieve that pressure. That pressure by itself can create further injuries. So you want to remove that. All of that happened in the acute diaphragm. And if you have an approach saying, I want to put the stem cells as soon as possible, then those stem cells will not survive if you just good them there by themselves. We show that if we put a scaffold, the scaffold provides a protective environment. So you can go in earlier and treat earlier and maybe have better improvement in regaining a function.

Richard Jacobs: Have you tried to put in scaffolding with a choice of where a nerve could go, like two paths, you know, wide junction and see what happens?

Jacob Koffler: Meaning to change the path?

Richard Jacobs:  No if you are given a choice. If you, If you put in not just a, you know, a pathway, one pathway, but a choice of let’s say two pathways, the pathway that bifurcates into two channels to see, um, how it, if it regrows differently and if it chooses one channel or another or both.

Jacob Koffler: Yeah, no we haven’t done that. Um, the reason is, um, you know, there are about a million axons in the spinal cord and again, there are different tracks and at the end of the day what you want to do is to keep regeneration in that track to improve the fidelity of regeneration. If, if axons go in different directions, um, one can get cantons potentially start experiencing pain. Um, one can have, um, wrong innovation, you know, an Axon can choose to go somewhere else. Um, and again, we don’t know how it, how it gets to its target.

Richard Jacobs:  It’s not to innovate someone in the wrong way but to see what happens if we use no. given axon a choice, what will it do? And maybe that would give some clue as to how the, uh, you know, how it knows that there’s a pathway there and how it follows a certain pathway. Do you have advice?

Jacob Koffler: That’d be interesting. It’s an interesting question. Um, it’s an interesting question. I know that people have done, uh, like a wife scaffold, not in the spinal cord but in, on, in vitriol and play. But there what they did, they already provided some chemical cues and the purpose of those experiments was to see which queue is more attractive to the Axon. So they provide different chemical cues on the, on each arm of the wife’s scaffolds. And then they, they follow how Axons regenerate and they sort of, we’re trying to understand which one is more potent and more attractive to pull the ax on stores and then, but experiments where there is no key on the other side, just let the axon go, um, freely. Um, when done in debt extent, you know, people, so here’s what people have done. So not in the, not in the, um, in the spinal cord but in the optic nerve. So the up the way the optic nerve work, and again, it’s, it’s the same thing. You have a neuron that extends axon, the neuron is in the eye and the extent axon to innovate back into the brain. In the middle. So when the axons go out from the, imagine axons go backward from the eye, backward to the brain, they don’t go straight. Uh, there is, uh, there’s an x form, it’s called the Chi. There is an X where there, there they sort of cross each other and there’s certain population from one side it would go only to one side and a certain population from the other side that would go to another side. Okay. They will cross, they would not make by themselves naturally, um, in development. And when people did injury, um, in the peripheral nerves, what they find, they don’t provide anything. What they find is that axons innovate equally, both sides instead of segregate. So I think in best contexts you can say that, um, axons would just go wherever they can.

Richard Jacobs:  It would be interesting if you put a, an attractant at the end of like a small maze and see if, uh, you know, as he acts on finds its way through the maze, somehow if it chooses a path. I know it’s a weird experiment, but I just thought about it.

Jacob Koffler: No, it’s an interesting experiment, people are doing that and we’ve been doing that as well. And um, so there’s, there is a growth factor. There’s a bunch of growth factors that are attractive for Axon. They can bring more acts on a specific point, those ones that are very potent. It’s called BDNF, brain-derived, brain-derived neurotrophic factor. Um, and it’s very potent for axons and people have been studying it for a long time. And if you injected in the spinal cord or in the peripheral nerve, you can see a lot of axons going towards where you have that. The problem is that BDNF because it’s very attractive when the axon reaches that point, they just stay there. They don’t go forward. Hmm. So, um, so the biology sort of, that’s why. So you know, naturally you have a variety of neurotrophic factors. You have a gradient of, of concentration. So people were trying to then tweak maybe to create multiple injections, maybe do a gradient. So, so yes, that’s, that’s a that’s another field that uh, we are involved in. Um, drug delivery, growth factors. Um, but nothing is easy in biology.

Richard Jacobs:  Yeah. I know you can’t do everything to establish to do.

Jacob Koffler: Yeah.

Richard Jacobs:  So what would be happy results for you in the next couple of years? What do you, uh, what are some of your milestones?

Jacob Koffler: I think that, um, you know, um, scaling up the technology too. So we’ve done low then studies, we show that it works with the rats and we have regained our function with rats and scale up the technology to do more free clinical studies to get closer. So the clinic, my, my personal goal is to try and, and develop something that I can say that reached clinical trials and, and you know, maybe had the chance to, uh, um, to healthy patients. And so I think that now that we have a proof of concept in rodents to scale up the technology to go to, uh, preclinical trials, um, if it good and good a, you know, results from me would be successful clinical preclinical trials that would then lead to a clinical trial, um, that can potentially, you know, have significant impact on patient’s lives. Um, so try and go, that’s the way in spinal cord injuries. Um, and maybe peripheral nerve injuries as well.

Richard Jacobs:  Very good. And what’s the best way for people to get in touch or to ask questions or to see more of your work?

Jacob Koffler: So we have the paper that published in Nature Medicine in January this year, and people can look for the title that you mentioned at the beginning. Um, and um, they can look for me Jacob Koffler at UC San Diego. Um, my email is on the paper as well, so people can, right. And I’ve been getting emails and people can’t get in touch in email quickly with their questions and, um, I’m happy to answer it as much as I, I know.

Richard Jacobs:  Very good. Well, Jacob, thank you for coming on the podcast. I appreciate it.

Jacob Koffler Thank you very much for having me.