Global Cast MD, along with Cincinnati Children's Hospital, sharing knowledge to improve child health around the globe. Hi, I'm M. Godi from Cincinnati Children's Hospital Medical Center. And last year in October 2022, Cincinnati Children's hosted the quad conference, which was a combination of four conferences. The International Organization for Esophageal Atresia, the Aerodigestive Society conference, the Cincinnati Children's Ery course, and the Cincinnati Children's Pediatric Dysphagia Series. And today our guest is Dr. Michael Helmrath, a pediatric surgeon and the director of Center for Stem Cell and Organoid Medicine, or Custom in short, at Cincinnati Children's. Dr. Helmrath brought us the coolest topic. We will hear from him on how they grow intestines and other organs in their lab. I cannot wait any longer. So let's start. When you look at the gut, it's it's commonly thought of as the kind of lining of the epithelium. And it's it's often forgotten about all the complexity that occurs within the gut, which is far more than just the nerves, the muscles, it's the immune system. It's recognizing luminal bacteria, microbiota, it's not just the epithelial lining, and that's a lot about what we do. Currently in the lab, they have developed methods to grow from a single stem cell drawn from the blood, the entire GI tract from the mouth to the anus. The first bowel that we made roughly 11 years ago was small bowel. And forusly, that was able to be transplanted into the animal. I will tell you that colon does it but not as well and it small, but the antral structures, the esophagus and the stomach did not and do not readily transplant into the animal. When they grow a single organoid in a dish, roughly for a month and put it into the animal, this is what it looks like. This is a human intestine on top of the kidney of the mouse. It is fully laminated. It looks no different than a biopsy that you have. And this is the EM structure of it. And importantly, it represents the patient. As I mentioned, nerves are not present in the graphs, they're just mesenchyme and endoderm, but we can add nerves by adding to the dish and when we transplant, our graphs are fully functional. Here Dr. Helmrath wants us to look at the bottom left. When nerves are present, it causes the ingrowth of vasculature that is human. So the cells in the graph that are endothelial progenitors are then told what to do by nerves. This is going to be important if you're using tissue for the esophagus. You get vascular growth with the nerves. They need to be there as well as we need to have the nervous component. A project in the lab that's just completing up by Holly pulling grew this these cells in a confined space. The idea here was to make a long tube. And that's what we show you that we did. But what we didn't expect and found was by growing it in a confined space, nerves were actually co-developed by not adding neuropheres but by progenitors within the typical HO. Human intestinal organoids, or HO, are three-dimensional self-forming structures created in the lab that mimic the original intestines characteristics, including its variety of cell types and how these cells behave. They saw that the nerves form much better compared to the time when Dr. Helmer's team add them externally. And these nerves are very similar to human controls that the team does. Peristalsis starts in the cells of Cajal in the mesenchyme and then they're affected and modulated by the nerve. And so this shows you the regular peristalsis that occurs. They can externally stimulate the grafts and block the nerve function with TTX, showing the concentration of the nerves and the relaxation can be blocked by L name. L name hydrochloride can be used in animal modeling to construct cardiovascular and cerebrovascular disease models. It has been widely applied for several decades in both basic and clinical research as an antagonist of nitric oxide synthase. So we demonstrate the ability of our tissue to both contract and relax. Again, all important things if we're going to build an esophagus. One of the things that we do in the lab is we separate out the HO in a dish. The inside is the epithelium or the endoderm. The outside is the mesenchyme. Think of it like an Oreo cookie. We take it apart, the inside's the cream, we can recombine the outside with any mesenchyme we want. What we basically show is that when we take apart, we isolate the mesenchyme and the endoderm, we put it back together, it is fully faithful. And so since the inside was red, it stays red. They can combine it with a different outside, which is green, and it stays green. That now allows them to take the mesenchyme from the HO and combine it with other endoderms. And here's what they did with the colon. It's fascinating, but how do they even foresee using this clinically? We came up with a model of damaging the bowel and putting fragments in. Here we took a rat, we divided the bowel, this is the end, and we're going to beat this up with hot EDTA and a brush. Inside the lumen, they're going to put fragments of their HO. And their control is these somatic stem cells that Dr. Helmrath talked about at the beginning of this video, and they're epithelial only. And what we find at seven days later, those controls, you really hear shown in in data, see that in graph. And it's shown brown is staining for a human staining KU80. But in the fragments that are the IPS generated, you not only getlia and graph but you getmal at seven days. And notice that it's not a confined space. These cells are migrating and proliferating such that 10 weeks later, when we look back at the animal, pretty much the whole epithelium is now human. The rat cells are blue and if you look at the muscle, you can appreciate the fact that the cells are aligned with the existing cells of the rats and they fully are functional. This shows the road map of getting to where Dr. Helmer's team wants to go. And this is really, really basic science research. What's very different is translating this into humans is really knowing what your target is and working backwards. We were fortunate at the institution Cincinnati Children's to be awarded uh something called Organoid Cure that's allowing us to put together the data to grow human intestine to put into a patient and we need to get FDA approval to do that. They have a space that's called the custom accelerator that is dedicated to translating the work the team does that works with world class scientists. And then the last question I can think of is, how do you get there? You have an ulcer and you want to treat it and you have the cells. How are you going to get the cells? How are you going to treat it? We have fragments. We can ask our GI colleagues to inject them. And then working with a group at Georgia Tech, we've developed a hydrogel that when you expose it to UV light, polymerizes like glue and will hold the tissue in place without killing the cells and the cells can migrate out. And so you can visualize yourself seeing recorrent structures. You dilate, you spray your cells, you spray a little UV light, it stays only there. I know Dr. Helmrath makes it sound so simple, but essentially it's a lot to do. I believe that the first step is just doing tissue agnostic and so intestinal transplants is just a tool to get us the information, but I think disease like esophageal strictures are very applicable to this and I do anticipate that we'll be using this therapy this decade in our patients. Well, this decade sounds pretty close, but we trust Dr. Helmrath and his team. In conclusion, Dr. Helmrath and his colleagues working at Custom at Cincinnati Children's have made significant advancements in growing human gastrointestinal tracts from stem cells. Their innovative techniques enable the creation of functional GI tissues, including nerves and vasculature, with potential clinical applications. They've successfully transplanted these tissues into animals, opening new possibilities for treating GI disorders and improving patient care. Thanks for watching this video. Don't forget to subscribe to the stay current MD YouTube channel. Follow our social media channels and download the stay current MD app for tons of content in pediatric surgery. Global Cast MD, along with Cincinnati Children's Hospital, sharing knowledge to improve child health around the globe.
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