Cultured Meat and Future Food is a short-form podcast series discussing the role of plant based food, cultivated meat and food technology. The show is focused on asking industry leaders questions for an audience with a non-scientific background. Cultured Meat and Future Food is targeted towards entrepreneurs interested in the food technology space.

Sophie Letcher – New Harvest Fellowship Series

Sophie Letcher is a PhD student and New Harvest Research Fellow in the Biomedical Engineering Department at Tufts University. She is a part of David Kaplan’s (growing!) cellular agriculture research group, and so far, her research as focused on two main topics. The first is using bioelectricity (endogenous electrical currents) to control muscle cell proliferation and differentiation, and the second is furthering the field of entomoculture (insect cell culture for food). Prior to starting at Tufts, she received her B.A. at Kenyon College in Neuroscience, then worked as a research technician at Brigham and Women’s Hospital in Boston, MA.

Alex Shirazi (00:04):

Thanks for joining us on the Cultured Meat and Future Food Podcast. On this episode, we’re excited to have Sophie Lecher. Sophie is a PhD student and New Harvest Research Fellow in the biomedical engineering department at Tufts University. She is a part of David Kaplan’s cellular agriculture research group. Prior to starting at Tufts, she received her BA at Kenyon College in Neuroscience, then worked as a research technician at Brigham and Women’s Hospital in Boston, Massachusetts. Sophie has been deeply involved in the cellular agriculture space and I recently caught up with her and her colleagues at the International Scientific Conference on Cultured Meat and Mare, or is ccm. We have a great episode for you here and it was actually recorded some time ago, but we’re excited to release it now. Sophie, welcome to the Cultured Meat and Future Food podcast.

Sophie Letcher (00:54):

Thanks so much for having me.

Alex Shirazi (00:56):

Sophie. Tell us a little bit about your background.

Sophie Letcher (00:59):

So I got my undergraduate Taki in neuroscience at Kenyon College in Ohio. And at this time I knew I really enjoyed learning about science and research and working in labs. But as I was approaching graduation, I, I knew that I kept wanting to do this kind of thing, but I didn’t know exactly in what direction. So I decided to take a job as a research technician to kind of gain more full-time lab experience. So I worked for two years as a research technician in a neuroimmunology lab in Boston at Brigham and Women’s Hospital. And again, I really enjoyed the research aspect of this, but I kind of found that I was getting more worried about the environment and motivated by research that kind of promotes sustainable innovation. And so this led me to the field of biomimicry. And so if people don’t know what that is, that’s kind of using nature as inspiration for sustainable solutions.

Sophie Letcher (02:00):

So this kind of idea that nature has evolved the most effective solution over billions of years. And so we can kind of take cues from that for human innovation. So as volunteering for the Biomimicry Institute and they have this really cool website called Ask Nature, if anybody hasn’t seen it, I would re definitely recommend checking it out. And my job here was to kind of just go find a bunch of sustainable innovations using biomimicry in academia or startups. And I remember actually the exact thing that led me to cellular agriculture is through looking at Ask Nature. And I was, I think I was actually sent by my mother <laugh> a, a link to a, the company called Eco which is not exactly bio but bio-inspired. And I thought that this was such a cool company, it’s using fungi as packaging and other applications.

Sophie Letcher (02:54):

And I saw that New Harvest was a partner of this and that was kind of the first time that I learned about cultured meat. So I went down this rabbit hole of looking at what this field was and I was just so excited by this idea because it tied together so many things that I’m personally interested in. So just the biology side of the research, so many interesting questions to answer the potential large sustainable impacts. So going back to doing, using biology for a sustainable purpose. And then of course the ethics and animal cruelty of the meat industry had always kind of been a guilty meat eater. So this is seemed like a great solution for me. And then thinking about food security and also just love thinking about food. So potentially pursuing a career where I can always think about food was exciting to me. This actually came full circle because I’m currently working with Eco ft some of their scaffolds, so that’s kind of fun. And yeah, so through this I found New Harvest and reached out to Dr. David Kaplan to apply to work in his lab in the biomedical engineering department. I was lucky enough to get accepted and be a part of the New Harvest Fellowship program and that’s where I’m at right now. So I’m currently a second year PhD student in David Kaplan’s lab at Tufts University.

Alex Shirazi (04:15):

That’s cool. And it’s, it’s interesting how so many people have different paths to New Harvest or cellular agriculture, whether it is some of the stuff that New Harvest puts out or the New Harvest Conference or you know, oftentimes we hear about people learning about the field in general through the mark Past Burger and so that’s definitely very interesting. Now you mentioned neuroscience. So for our audience and for my own purposes, <laugh> can you give us like a, a very explain it like a five answer of what neuroscience is in general

Sophie Letcher (04:52):

<Laugh>? Yes. So that’s the study of the brain and the nervous system, so not very food focused actually. And so research that I was involved in at that time was looking at how the immune system, so cells of the immune system work to kind of progress neurodegenerative diseases. So that was, yeah, again, not super super relevant to meat research, but a really fascinating field.

Alex Shirazi (05:22):

Right. And, and I think neurodegenerative diseases are, are something that are a very big challenge right now and I’ve seen that there’s some pretty nice work coming out of the Chan Zuckerberg initiative trying to tackle that field.

Sophie Letcher (05:36):

Yeah, yeah, definitely.

Alex Shirazi (05:38):

So I wanted to ask you, so you, you learned about New Harvest and so can you tell us like what your initial thoughts were after you went into that rabbit hole? So you, you reached out and how was the overall process of getting in touch and also like setting up a program with New Harvest?

Sophie Letcher (05:57):

Yeah, so it was <laugh>, it was actually kind of very fast since I, when it, once I first found it, so I kind of immediately reached out to, I saw I was in the Boston area so I saw that there’s the New Harvest fellows, Andrew Stout and John Uen and Natalie Rubio who were all at Tufts University at the time. And so I reached out to all of them along with Dr. Kaplan and met with them I think maybe within just a few weeks of, of finding it. And so I came to Tufts and I talked to them and they were all saying, I think my thought was, you know, maybe additionally meet with them and over the next year or so I’d kind of see how this field progresses and see where I can fit into it. But they really encouraged me to just apply right then.

Sophie Letcher (06:44):

And so I think at that point that the proposal was due in a a few weeks so I had to <laugh> very quickly kind of get everything together and form a proposal, which includes kind of writing a research plan for up to three years. So you kind of think of goals and yeah, like an overall timeline of, of research you would like to accomplish that would accelerate the the field of cellular agriculture. And luckily at that point I already had some ideas of things that I would like to contribute. Yeah. And at this the same time that I was putting together this application, which is your, your research proposal, I was also applying to the biomedical engineering department. So I did those at the same time. I think for me also it was, I hadn’t initially planned to go into biomedical engineering cuz as I mentioned I was a neuroscience major as may be more interested in biology. But again they encouraged me that this was a really good field to go into. I’m very glad that I did. Yeah, so you apply and put together this proposal and then there’s kind of a, a review process and then the program kind of started when I started at Tufts.

Alex Shirazi (07:58):

Thinking about that process when you’re applying to the program, if certain grant money doesn’t come in, you’re gonna have to find other grant money for your program. Is that right?

Sophie Letcher (08:09):

Yeah, yeah, that’s what’s right. I think a lot of PhD programs will kind of cover maybe the first year or so. So it’s not necessarily always expected that you have funding when you come in, but especially in the field of cellular agriculture, it’s very exciting to be able to have this funding when you first come in.

Alex Shirazi (08:27):

Absolutely. And so you created a research plan. Tell us a little bit about some of the research that you are working on when you first started and what you’re doing now.

Sophie Letcher (08:37):

Yeah, yeah. So my research proposal was talking about using bioelectricity to control cell behavior. And so I began, I think a lot of my first year was focused on this bioelectricity project and then I’ve since started continued to work on this but also focused on advancing entomo culture. So insect cell culture has started by Natalie Rubio and that’s kind of been a lot of my focus recently.

Alex Shirazi (09:10):

We spoke a little bit about bioelectricity the, the first time we we talked, but I had never heard of the term. It’d be awesome to break down what that means and how it’s applied to sell ag.

Sophie Letcher (09:21):

Yeah, exactly. So it’s a really fascinating field I think. I’m biased though <laugh>. So I guess to go over it, the rationale for this project is, so meat is kind of mostly made up of muscle and fat, but this project was focusing on muscle specifically. And when muscle develops you have stages of proliferations, this is cells multiplying and then differentiation. So cells fusing and maturing. And so for cultured meat purposes, we would like to have control over each of these steps. So this would kind of contribute to maybe enhancing the speed of the process or maybe driving down the cost or creating more accurate, creating more meat products that are more like animal produced meat products. And so that kind of brings us to thinking about how muscle develops in an animal. And there’s this field of developmental bioelectricity and this is kind of catalyzed by Dr.

Sophie Letcher (10:24):

Michael Levin who’s in the biology department at Tufts. And so this is the idea that, you know, usually when you think about electricity in in cells or in biology, people think of neuroscience, right? So that’s, especially me, I came from a neuroscience background. I thought electricity is, you know, neurons communicating in the brain, but actually every cell has a charge and this is kind of governed by the ratio of positive and negative ions inside and outside the cell. And by ions X mean things like sodium or potassium have positive charges or chloride has negative charges and these are all kind of floating around in the body in in different concentrations. And changes in this charge that are communicated across cells can kind of instruct tissue development. It can actually override existing genetic signals. And so to kind of, I guess maybe simplify this positive charge as kind of a Q2 grow or proliferate, whereas a negative charge means mature.

Sophie Letcher (11:33):

So in in muscle this would mean fuse and differentiate. And so the idea is kind of to capitalize on this when trying to grow meat because this field hadn’t really been applied to meat, it was mostly studying development. And so I guess how would we do this? It would be, you can just change for example, like change the potassium concentration in the culture media. So that’s just the liquid that the cells are going in. Or you could kind of alter, one thing I worked on was using drug treatments to alter the kind of gates in the cell membranes that allow charges to pass through with the goal to kind of use these signals that the cells already know how to interpret, to push them to behave how we want to. And then so the original proposal is using this idea in multiple different species.

Sophie Letcher (12:27):

So in cow cells, in insect cells in maybe branching out to kind of any of the other cell types that the lab is currently working on. Yes, that’s kind of the overall idea. I think this is, this is exciting to me just cuz I love learning about how the tissues naturally developed just because that’s so fascinating. But also this idea that if we can use these cues to instruct kind of natural patterns, maybe we can push them to go beyond their natural state, you know, like maybe make a really, really thick muzzle fiber that wouldn’t normally develop but by, you know, telling them to keep developing or something. I think that’s fun to think about.

Alex Shirazi (13:10):

I’m almost thinking like this could be, you know, a future where you have, right now we have like, you know, different cuts of meat, but in the future we might have kind of like different levels of, of meat. I mean I don’t know what you would call it <laugh>, but like different types of meat based off of how this is like manipulated potentially, right. Like you said, like you know, thicker muscle fibers or whatever it may be.

Sophie Letcher (13:33):

Yeah, yeah, exactly.

Alex Shirazi (13:35):

And so you did a good job of explaining how to like manipulate the bioelectricity, but how would you measure it? Would it just be to kind of see how it is changing or different?

Sophie Letcher (13:47):

Yeah, yeah. So I guess there’s different ways to look at it. What is to just, how do you measure that the, the charge of the cells actually changing? And so to do that there’s, there’s this voltage sensitive dye that you can treat the cells with, which is really cool. And so the cells will uptake more of the dye if they’re more positive and not take as much up if they’re more negative. And so you can use that to study if you know your treatment are is working and then on the side of how do you, how do you tell if it’s, if we’re pushing the cells to grow better, if we’re pushing them to, to differentiate better. And I guess on the growing proliferation side you can just measure cell growth over time. So if you stimulate them a specific way that you hope that they grow better and you measure the number of cells over time and you can tell it grows better in comparison to no treatment, then that’s a great result.

Sophie Letcher (14:44):

And also just kind of making sure the cells look healthy this whole time, there’s a bunch of assays you can do for that. And then on the differentiation, muscle maturation side something that we do a lot, which is pretty standard in the, the muscle biology field is looking at something called fusion index. And so this is something so in muscles butcher they kind of do a bunch of different things, but two main things I think I mentioned before, they fuse together and then they also start expressing different proteins. So you can visualize expression of this protein as well as see that the cells are fusing and quantify this as a measure of fusion index.

Alex Shirazi (15:31):

As you were talking about that I was just thinking about yeah this, this might be kind of like the really kind of an interesting way to, for us to look at the overall process and and think about how many different ways we can fine tune, you know, cell cultured meat technology for example, or any type of cellular agriculture technology to where you start having these, I guess like deltas or differences that are not, and I hate to say this word, but not in the, in the natural occurrence of, of growing an animal but could be better in terms of, I don’t know, taste, texture or, or whatever it may be. And, and so that’s kind of cool to think about. I think that, you know, if if you really look at at what things could be it, it is this, this world where we could have more control over things and, and I think that is a, a better f food future and and I think sure it’s not as appealing or might be considered, you know, lab grown, but I think that is a way we can get to a, a better food future.

Sophie Letcher (16:39):

Yeah, exactly. I think it’s kind of, I always think it’s a diff interesting kind of balance to strike between, you know, how much do you want to manipulate or how much do you wanna make it exactly like the animal. Cuz I think, I guess I think a lot when we, you know, we’re taking cells out of a animal that when these cells are growing within the animal, they’re exposed to, you know, we don’t even know how many cues from different cell types around them and you know, hormones and signals and things that are being changed just by how the animal interacts with its environment as well. And then we kind of take just one cell type out and try and grow it in a lab and it’s crazy to me that it even grows at all and works at all. So I guess I’ve always fascinated by, by just the fact that this works so far, but I think taking, going back and, and taking cues from how, like what other signals are these cells getting when they’re developing in vivo and how can we bring that into the lab to create products that are more like the natural cut of meat.

Alex Shirazi (17:48):

Absolutely. So you mentioned that you kind of, you were winding down that research and then you moved towards in tomo culture or some of the work that Dr. Natalie Rubio was working on. How did you kind of make that transition and and how did you cap off that initial research?

Sophie Letcher (18:09):

I would say that research is still semi ongoing. I’ve just kind of focused mostly on insect cells at this point and hope to kind of start the bioelectricity stuff back up soon. So I guess how I started with the insects is as, because they were included in my original bioelectricity proposal and then of course Natalie was, was working on these cells in the lab and so I started to learn how to culture them with her and I got really fascinated by the insect cells themselves and they’re just really fun to work with, really interesting to work with and have a lot of kind of open avenues of, of questions that we would like to answer about them. So if people are not familiar with this, it’s the idea to kind of isolate the same cell types, so muscle and fat cells that we use to create traditional livestock cultured meat using cows or pigs but using insect cells instead.

Sophie Letcher (19:06):

And the reason is because these cells have a lot of really interesting qualities that make them easier to grow and potentially easier to scale up and more cost effective than these traditional cell sources. So for example, they can grow at room temperature without co2, whereas mammalian cells need to kind of be he heated to physiological temperatures, which can take a lot of energy. They also survive off fewer resources they don’t need, there’s a lot of talk in the industry about kind of how expensive growth factors are. They actually don’t need these when they’re being cultured if fewer toxic byproduct buildup as they grow. So that just means they need less culture media as they’re growing. There’s also a lot of other, I can go <laugh> I can talk for a long time about how all their, their cool qualities, they can also grow either adherent, meaning they’re just stuck to a dish, which is how most cell types that we work with grow or they can also grow in suspension, which it just means floating in culture liquid, which could be a lot easier for scaling up and yeah, they’re just kind of a lot harder and more adaptable to changing conditions.

Sophie Letcher (20:17):

So that’s why we work with them.

Alex Shirazi (20:19):

Great. And so is the, the work on the insect cells related to bioelectricity as well?

Sophie Letcher (20:27):

So currently, no, but I think my hope would be that bioelectricity could kind of be a tool that could be applied to multiple, multiple different cell types and cell species. But I guess one of the challenges being that we don’t really know how it would affect insect cells. And so I’ve done some kind of of pilot studies using them and it and it looks like they kind of do react differently with than mammalian cells. So I think that requires a lot of optimization in the future.

Alex Shirazi (20:57):

Cool. What is your research focusing on with entomo culture now?

Sophie Letcher (21:01):

A lot of it has kind of been focused on optimizing this muscle and fat cell culture from insect cells and specifically from a insect called the tobacco horn worm or manduka sex that Natalie started work with before I got here. And so, so yeah, it’s been kind of trying to get each of those cell types to grow and recently kind of sci-fi arm of this has been thinking of ways to grow these for outer space, which was motivated by our participation in the deep space food challenge. And so that was kind of thinking of ways to scale up this technology to kind of make it more realistic as a start to finish process.

Alex Shirazi (21:47):

How did your team get introduced to the deep space food challenge? It seems like an exciting opportunity to kind of work on that challenge.

Sophie Letcher (21:55):

Yeah, yeah, it was a lot of fun. The challenge was to create a solution that could feed a crew of four astronauts on a three plus year mission to Mars. So I was kind of thinking of a, a way to produce food with the fewest inputs to get the most output. This was kind of brought to our attention because a lot of the kind of characteristics that make insect cells so exciting just for in general cultured be also could make them really adaptable for growth in such a kind of challenging low resource environment. And so it kind of, that’s how it got brought to our attention. And then throughout the process of applying and and coming up with our solution for this, I think for me it was really exciting to see the kind of potential for insect cells be put on a spotlight in this way. And also thinking about how the solutions that we could generate through this challenge would could apply to just advancing the field in general for for use on earth.

Alex Shirazi (23:05):

Yeah, no, that’s cool. And I think one of the criteria was also having like a, a small footprint in terms of like square footage you use to dedicate to growing food and the benefits you mentioned such as like not needing to control temperature as much and and that kind of thing I think work very well when, when you think about space and limited resources.

Sophie Letcher (23:27):

Yeah, yeah, exactly. And kind of as a a fun side note, there’s been some research in a long time ago you, so insect cells have been researched throughout history in the biotechnology field, but there’s been some research already growing cells in simulated microgravity insect cells in simulated microgravity and they seem to maybe even grow better. So that’s kind of fun.

Alex Shirazi (23:51):

That is cool. So that’s really exciting and, and I think, do you have a timeline on the existing research with in Tomo culture in terms of maybe what the next project will be or is that to be decided?

Sophie Letcher (24:06):

There’s a lot of directions that can go and it’s actually pretty exciting. So Natalie Rubio is unfortunate for Lee for me leaving Tufts because she defended her thesis as you said, Dr Na, Natalie Rubio. But there’s, I’ve been working on it and there’s also three master students currently Erin Rena and Kirsten who are all contributing to the entomo culture project as well. So for example, they’re looking at nutrition of insect cells looking at different ways to preserve insect cells and maybe a more sustainable way than traditional ways we preserve cells or looking at the economics of of cultured insect cells cuz kind of getting hard numbers on how this would compare to mammalian cells. So is there some research directions? And then I think also looking at 3D culture, best ways to 3D culture, growing large quantities in suspension and and things like that.

Alex Shirazi (25:07):

You mentioned working with some of the masters students in your program, but I wanted to ask about some of the other New Harvest fellows at Tufts. And so I’m sure you work with them regularly, but do you interact with them outside of kind of the lab?

Sophie Letcher (25:23):

Yeah, yeah, for sure. So, so yeah, there’s John Yen and Andrew Stout and Natalie is still kind of involved with the the lab as well and we definitely interact a lot both inside and outside the lab. It’s a really great group and I feel really, really lucky to be able to be involved with them and to be working in kind of the, the lab that they all started. So yeah. Yeah, we we spent a lot of time together.

Alex Shirazi (25:51):

<Laugh> I wanted to ask you about some of kind of like the positive effects of the 10 million grant and if you’ve seen any noticeable changes once that came in.

Sophie Letcher (26:02):

Yeah, yeah, for sure. It’s been, it’s really exciting to see it. So I guess as being the kind of first official US government funding of cellular agriculture, it’s just, I think for everyone it’s really motivating to see kind of the, the work in the field being recognized like that. And then I think, you know, a big part of this, it wasn’t just Tufts for this 10 million grant, it’s a collaboration between five different universities. So for example, the obvious support lab at Virginia Tech was really instrumental in getting this grant. So I think one big thing we’ll see in the, the future is a lot more collaboration with, with these different universities, which is really exciting for us. And also kind of advancing the technical development of the field. I think that will be really helpful. We haven’t seen that yet because it’s, it’s been so recent, but I think that will be through this collaboration kind of seeing other universities working on cultured meat and sharing knowledge and resources and stuff will be really exciting.

Sophie Letcher (27:10):

And also focusing on further educational aspects. So there’s already some current education initiatives that we have going at Tufts. So like the cellular agriculture course that was started by Natalie, John and Andrew a couple years ago and is now part of the biomedical engineering curriculum at Tufts. So expanding these education initiatives here I think will be a big future impact of this grant. Baby creating, I think in the works is a cellular agriculture certificate program at Tufts, which is really cool. So you could kind of graduate, graduate with a degree in biomedical engineering and certificate in cellular agriculture. And I think also exciting is just kind of setting a precedent for maybe future government funding at other universities as well.

Alex Shirazi (28:03):

That is really exciting. And I think when that announcement came up there was, you know, talks about the U S D A and the National Institute of Food and Agriculture to develop this National Institute of Cellular Agriculture. Do you know if there’s any announcements or advancements in regards to what that might look like?

Sophie Letcher (28:22):

I’m not sure exactly what it will look like. I guess a lot of it is just this enhanced collaboration and knowledge and resource sharing, but hopefully can update, you know, maybe in a couple years when that’s advanced a little bit more what it actually looks like here.

Alex Shirazi (28:38):

Absolutely. And so this has all been very exciting, especially the, the path that you’ve taken some of the research that you’re doing and right now people kind of joke or there’s like a myth, I think sometimes it happens, but this idea of like massaging cows for Wagyu beef, <laugh> <laugh> and, and so in the future we might have like, you know, this idea of bioelectric applications for having better Wagyu beef <laugh>. Yeah. And I know and some of these yeah. And some of these other fine tuning elements, but I wanted to broaden it up and ask you if you had any advice for others that might be interested in either pursuing a PhD or maybe even if they’re not even at that stage and they’re interested in, in getting into a program to eventually do work in cellular agriculture. Do you have any advice for them?

Sophie Letcher (29:31):

Yeah, yeah, for sure. I think definitely they should do it <laugh>. But also just kind of we’re lucky as the field has advanced, a lot of resources have been put out there. So like this podcast is really great to listen to. Also kind going to conferences, looking at recordings of conferences and, and reading a lot of the resources that have put out there. And then I think just reaching out and talking to people in this space, it’s a really welcoming and friendly community. I think just because people are really passionate about this field when they’re, they’re in it because there’s a lot of kind of personal stake in it as well as academic interest in it. And so I think, you know, people are really excited to talk to people who want to break into the field. And then I guess also something I would say is to kind of not feel limited by the field that you’re already in.

Sophie Letcher (30:27):

So I think I’ve talked to a lot of people who say, you know, I don’t have a degree in in biomedical engineering, so I don’t know how I could contribute or something. But I think that the field actually really benefits from people with different experiences in different backgrounds and actually needs more people from different research areas. So to kind of not, you know, box yourself out of the field because you don’t feel like you could fit into it, but kind of to more openly think about how you could contribute despite what your current experience is.

Alex Shirazi (30:58):

Great. Well thank you very much. You can connect with Sophie on LinkedIn and learn more about New Sophie, do you have any last insights for our listeners today?

Sophie Letcher (31:12):

Yeah, I would just emphasize don’t be afraid to reach out if you are interested in the field and get involved.

Alex Shirazi (31:19):

Thank you so much for being a guest on the Cultured Meat and Future Food Show.

Sophie Letcher (31:24):

Yeah, thank you so much for having

Alex Shirazi (31:25):

This year, host Alex and we look forward to seeing you on our next episode.