Jaejin Cho, CEO of CellinCells, explains how the company’s proprietary Tissue Reforming Technology Platform (TRTP) translates developmental biology and quantitative tissue design into scaffold-free therapeutic tissue modules. He discusses the Phase II development of TRTP-101, the TRTP-201 cartilage programme, AI-enabled process monitoring, and the company’s partnership strategy for global clinical translation.
Let’s start with the technology underpinning the company. Where did the original idea for your tissue-reforming platform come from?
It goes back to around 2008 or 2009. I was thinking about mass versus single cells, and about surface area. If you administer cells as micro-blocks rather than as single cells, it enhances cell-to-cell interactions, preserves the cells’ autologous extracellular matrix (ECM), and improves local retention and engraftment in the target tissue or organ. A mass, by contrast, has a much better chance of surviving that journey. That was the starting point – the idea that shape and scale matter enormously, even though at the time I had no proof of it. Beginning around 2010, pioneering work by researchers such as Yoshiki Sasai, Jürgen Knoblich, and Hans Clevers demonstrated that stem and progenitor cells could self-organise into three-dimensional tissue-like structures. Much of the field remains focused on modelling and drug discovery, while translation into reproducible therapeutics is still emerging.
You subsequently attended several major stem cell and organoid conferences. What did you take away from those meetings?
By 2019 I was attending the International Society for Stem Cell Research meetings, including one in Sydney and Melbourne, and the following year there was a major organoid-focused meeting in Los Angeles. What struck me was that, however beautiful the imagery – all that colour, all that structure – the fundamental question remained unanswered: what can you actually do with it? If you cannot regulate or control it, it remains excellent research, but it is very difficult to translate into something applicable in real life. So I turned back to developmental biology itself, to the textbook stages of how organs and tissues actually form in mammals, including humans – the blastula stage, the gastrula stage, right through to the formation of the gut. I looked at how different organs, despite having entirely different names and functions, go through remarkably similar early stages. Cells in our TRTP platform begin to migrate, compact, and condense, driven by mesodermal or mesenchymal cells, gradually taking on a cup-like shape reminiscent of key developmental processes. Once this shape forms, the tissue is essentially committed to becoming something specific – you can see this pattern behind the development of the central nervous system, the gut, the kidneys, the lymphatic system, even teeth, where we call the earliest structure a “tooth bud.” The question I kept coming back to was how to mimic that process, and how to control it once we could.
That sounds like a purely scientific pursuit at first. How did you turn it into a business?
My thinking was actually quite simple. There are countless published protocols for differentiating stem cells, but if I could reproduce this natural condensation phenomenon in vitro, the process itself would be far faster and more mature than people assumed, because in normal development this stage happens very quickly. So I started to treat it almost as a mathematics problem: how many cells are needed, and what forces drive condensation? I built what I eventually named “micro-blocks,” and found that different combinations of these micro-blocks could reliably produce cup-shaped structures.
Other researchers and companies have their own approaches to standardising and making these processes repeatable. Our platform combines developmental biology with quantitative design principles, including defined cell numbers, assembly geometry, and culture parameters, to improve reproducibility and standardisation. It took considerable effort to establish these conditions, but eventually we built what we call our tissue-reforming technology platform, structured around two core steps, which I would describe roughly as a condensation step and a shaping step.
Because the process is driven by calculation rather than by any single predetermined biological pathway, we can then apply known, simple differentiation conditions to steer a structure toward becoming a precursor for a particular organ or tissue. My idea was that you could essentially create a large number of these pre-organ structures and transplant them directly into the tissue requiring treatment.
Your lead asset, referred to as TRTP-101, has just completed phase I trials. Can you tell us more about it?
Nobody had really attempted this approach before. My own background is in toxicology, so my first instinct was to worry about what kind of toxicity this modality might create, given how different it is from anything else. That concern stayed with me for roughly a decade and led me to a broader scientific question: how do you remove that risk scientifically while creating a therapy with meaningful biological activity? Greater biological activity in stem cell therapies requires more rigorous safety characterisation to better understand and manage potential risks.
Across development, many tissues are formed through recurring morphogenetic processes, including cell migration, condensation, folding, and tissue-specific patterning. We asked whether selected elements of these processes could be reproduced and quantitatively controlled in vitro. In our TRTP platform, mesenchymal cells self-organise through condensation and shaping into reproducible tissue modules that can then be directed toward specific tissue phenotypes.
Skin turned out to be the right place to start, partly because there are already many treatments and specialists available if something goes wrong, and Korea has a particularly strong, well-regarded dermatology community. So I began testing there, while also thinking about the broader industrial and commercial application – and for that, you need an actual market.
If skin is the starting point for proving the technology, what does the commercial opportunity look like today?
Medical aesthetics. If we can treat scarring – whatever its origin, whether from skin cancer surgery, acne, or wound healing more generally – that residual scar tissue represents a very large market opportunity. At the same time, I did not want to build our first proof of concept around patients suffering from severe, life-and-death conditions such as ALS or Parkinson’s disease. Some of my own colleagues have pursued organoid approaches directly in those areas because of their obvious medical importance, but I did not want to use those patients to prove an entirely new modality. Skin is a clinically accessible, easily monitored, and manageable tissue, making it a reliable starting point for initial evaluations.
Was the idea to start with skin as a way of proving the concept, before expanding into other indications?
Exactly. The real difficulty was that Korean regulators simply had limited experience assessing something this novel, so the process of obtaining IND approval and running the clinical trials took far longer than expected. We are actually meeting the head of dermatology at Samsung Medical Center soon, as well as colleagues running an official clinical study at Seoul National University Hospital. It has taken longer than I expected, but Korea has, in the meantime, become genuinely famous in cosmetics, and the dermatology field here now sits at a very premium intersection of medicine and cosmetics that barely existed ten years ago. Korean dermatology companies do this exceptionally well, and they are actively looking for genuine regenerative products to add to their offering – something that, within Korea at least, currently only we can provide.
What does the competitive landscape look like? Is anyone else developing something similar, in Korea or globally?
I have not found anyone doing exactly this yet. I recently met representatives from one of the top five global pharmaceutical companies at the BIO International Convention, who approached us. Two of their people, one from business development and one a senior researcher, told us our technology and approach were quite unique and broadly applicable, and they wanted to understand which indications we were pursuing and to stay in touch. I also met with buyers from another company in the space. We are a small team, but we are steadily building out our business development and licensing capabilities around this interest.
For the TRTP-101 programme specifically, the origin was really about toxicity. I was confident there would be meaningful efficacy, but if there is real efficacy, there has to be a genuine question about toxicity too. What I had not initially appreciated was how much simpler skin is in that respect – one side of the skin faces the outside air, whereas if you are working with an internal organ, the treated area is surrounded by tissue on every side. That difference matters enormously, and we have since worked through it, though it cost us considerable time and money.
Looking ahead, what are the key programmes in the pipeline, and which indications do you see as the most promising opportunities for the company?
We dosed our first patient in the second trial this month. We are also preparing an orthopaedic programme focused on the knee, currently designated TRTP-201, with earlier-stage candidates behind it in our naming convention. Because our platform is grounded in calculation rather than case-by-case biological trial and error, moving into new indications is comparatively straightforward for us. We believe TRTP-201 is genuinely promising as a treatment for cartilage defects and osteoarthritis – true structural regeneration, not merely symptom management. We already have supporting regeneration data in mini-pig and rabbit models, though bringing a genuinely new modality like this through the regulatory system still requires a great deal of groundwork.
There are three things that need to be addressed to meaningfully treat osteoarthritis: inflammation, pain, and structural repair of the tissue itself. Most existing therapies, including Korean products, focus primarily on reducing pain and, to some extent, inflammation, which for patients everywhere tends to be a vicious cycle, but there is currently no approved organoid-based regenerative therapy for osteoarthritis in Korea, while current treatments include those focused on pain control.
Does this reflect the challenges of evaluating a genuinely novel modality, or the fact that both the science and the regulatory framework are still evolving globally?
Novel modalities often lack established precedents or product-specific evaluation frameworks, so sponsors and regulators must work iteratively to define appropriate evidence. Advancing TRTP-101 into Phase II has been resource-intensive for an emerging biotech. Having reached this stage, we are now well positioned to pursue domestic and international partnerships for later-stage development.
How have you financed the company so far, and what is your plan for the later-stage trials?
We have spent a great deal already. We have a partnership with Soulbrain Holdings, which came in as a minority investor, alongside a co-development and licensing agreement to build a cancer organoid testing model together. Our largest investor, though, has been Korea Investment Partners, a leading Korean venture capital firm. Altogether, we have spent in the region of USD 15 million, and we now need considerably more – with a targeted financing round planned in the near term, followed by larger sums required for the later-stage trials.
We are preparing for a KOSDAQ listing, subject to the required review process and market conditions. In the meantime, we still need to raise a targeted financing round, likely in the low tens of millions of dollars, and we are actively securing capital for Phase II and pipeline expansion. Despite persistent financial challenges, we continued to address each challenge and make progress in our development.
It has been a genuinely difficult few years to raise money in biotech, particularly since COVID, and many companies have closed. You are still here. What has kept you going?
I built this company because, years ago, I first assembled this system essentially on my own desk, in a small room, while still working as a professor – and I realised I could not properly develop or realise its potential from within a university setting. At the time I assumed that if I published the underlying technology, someone else would take it forward, but nobody did, so I ended up having to build it myself, from beginning to end. The real reason I built the company was to actually see certain patients, with certain conditions, treated using this modality – that is what has always driven me. Along the way, I have come to understand that partnership is not only about raising money. A larger company brings resources and existing relationships with hospitals and doctors, and what I want, more than anything, is to introduce this modality to patients as quickly and as properly as possible. What I underestimated was how long it actually takes to help other companies and researchers genuinely understand something this new.
We have also developed an adjacent commercial application of the platform: a cancer organoid testing system. Using the same underlying technology, we can produce scaffold-free, self-organising three-dimensional tissue constructs at millimetre scale. We are not building a consumer cosmetics business; our core focus is regenerative medicine, while partnering the platform for selected adjacent applications.
With clinical development under way and an IPO on the horizon, how do you make sure you stand out? Korea alone has some six hundred biotech companies, and China has a great many more. How do investors find you, and how do you find them?
We have been attending far more workshops, conferences, and government-run innovation events, both domestically and internationally, actively presenting our company and our technology and looking for the right kind of international partnership. If I am honest with myself, I know that the single most effective thing I can do, from a business development standpoint, is simply to be visible more often – to show up. The dilemma is that doing so takes a great deal of time, on top of running two research programmes simultaneously and continuing my academic responsibilities, including committee work at the university. It requires far more people, both scientific and financial, than we currently have. But I remain genuinely confident that our underlying approach is fundamentally the right one, and I think the upside for the company and the technology is considerable, precisely because we are not simply copying what everyone else in the organoid space is doing.
I think of it a little like the film Dune – there is a very narrow path through, and we are walking it.
How do you see the road ahead, given the manufacturing and regulatory complexity involved?
We can manage a great deal of it ourselves, because our manufacturing process is grounded in calculation and has effectively been supported by AI-enabled image analysis and process monitoring, but we remain limited in manpower and infrastructure. So the challenge is one of focus. We will keep walking this narrow path, while our team continues developing and maintaining supporting technologies alongside it. In aesthetic medicine and therapeutics, for example, Korea’s industry encompasses a range of materials and technologies, including fermentation-derived hyaluronic acid fillers, botulinum toxins, polynucleotides, and advanced extracellular matrix materials, each with distinct characteristics and applications. That is the direction we are also moving in, and we will keep collaborating with other companies who can support that side of our development and help us maintain financial stability, alongside continued backing from venture investors and strategic partners such as HK Kolmar, part of the wider Kolmar Group, which is also an ally of ours. Our goal is to increase the proportion of operating expenses supported by partnering income, while using strategic and venture capital to fund clinical growth.
