🧬 A Dynamic Bioprinting Hydrogel Made From…Crabs?
Chitosan-Based Biomaterials for 3D Bioprinting, Tissue Regeneration, and Drug Delivery This month, we sat down with Dr. Hafez Jafari. Dr. Jafari is a postdoctoral researcher in biomaterials at the University of Brussels. He began his journey into the world of 3D culture during his master’s thesis in 2016. Dr. Jafari studied chemical modification of cellulose nanocrystals to enhance stem cell-driven bone regeneration. Later, during his PhD, he developed adhesive hydrogels from natural sources like chitosan for wound healing and bleeding control. In 2023, as a postdoctoral researcher at Ghent University, he worked on nanozyme nanomaterials that mimic natural enzymes to improve diabetic wound healing by addressing inflammation and other complications. Currently, he leads a proof-of-concept project at the University of Brussels, developing chitosan-based biomaterials for 3D bioprinting, tissue regeneration, and drug delivery. These materials are designed for 3D printing organ models used in drug testing and studying cell-material interactions within a 3D matrix. Transforming Chitosan into a 3D Innovation Platform Describe your current proof of concept project. Do you see your research evolving into products for specific applications? Dr. Jafari: The proof of concept is about developing raw material for 3D bioprinting. It’s not tied to a specific application yet, but it can be used in wound care. It could also be used for creating 3D models for drug testing, and possibly for tissue transplantation, although we’re still far from that. Right now, the focus is on expanding the portfolio of biocompatible biomaterials that can work with cells for different types of applications. Is your chitosan-based biomaterial meant to be an alternative to existing bioprinting gels? Dr. Jafari: Let me give a brief introduction to chitosan. Chitosan is a natural biopolymer derived from chitin, which is found in the shells of crustaceans like shrimp, crabs, and fungi. We have both animal-based and non-animal-based sources available. It’s an interesting biomaterial because of its inherent biological properties. It’s: That means it has potential for a range of applications, like tissue regeneration and bone healing. But it has some limitations. The main one is poor solubility. It’s not very soluble in physiological conditions, and it needs an acidic medium. That makes it difficult to use in applications like 3D bioprinting, which need physiological conditions where cells can thrive. It can also be used in different types of product formats like films, hydrogels, fibers, or sponges, depending on the application. That’s why we already have quite a lot of chitosan-based commercial products, especially for wound care. In our current project, we’re chemically modifying chitosan to address these limitations. Chitosan in the form of a hydrogel has a brittle structure due to its intermolecular hydrogen bonds. We’re trying to increase the flexibility, improve the viscosity and viscoelastic properties, and, more importantly, address the low water solubility and printability. In the lab, I experienced these limitations because I used to work with chitosan during my PhD. I thought it would be great to address the limitations of chitosan and use it for 3D bioprinting. What specific problems with alternative hydrogels led to the search for a better solution? Dr. Jafari: I wouldn’t say it was a specific limitation with other hydrogels. But the fact is, bioprinting technology is advancing quickly, while the materials used for 3D printing are lagging behind. We have different types of printing: volumetric, extrusion-based, and digital light processing, but not many materials can be used for these. I want to expand the portfolio of materials that can be used for different types of printing platforms. Building 3D Skin Models for Chronic Wound Testing What would be the first product you’d like to see come out of this research? Dr. Jafari: At this point, it’s more investigation and exploring the possible opportunities. One possible product could be chemically modified chitosan that can be used for 3D bioprinting, like a bioink with unique properties that aren’t currently on the market. Could you run me through one of the types of assays that you perform when it comes to the 3D model side? Dr. Jafari: One of the most advanced assays I am developing now is to see the effect of nanozymes in a 3D model of inflammatory skin tissue. The idea is to build a model that can mimic what’s happening in chronic wounds in diabetic patients, where: are quite challenging for healing. And that’s the major problem. So, we start by using this chitosan-based polymer material incorporating primary human dermal fibroblasts and keratinocytes, because these two cells are the key players in skin repair. Once the printed construct is stable and the cells are well distributed, we induce oxidative stress or inflammation using external stimuli such as hydrogen peroxide or inflammatory cytokine. These stimuli can mimic the chronic wound environment, where cells are exposed to high levels of reactive oxygen species and inflammatory segments. Then we introduce our nanozyme with enzyme activity to see if this nanozyme can alleviate the hypoxia, produce oxygen, and affect the cells in 3D environment. There are some challenges, specifically in terms of imaging. When working with 3D systems, like bio- fluorescence imaging systems, it’s challenging for some specific staining. For example, checking intracellular oxygen or ROS levels, such as superoxide anion, cell morphology, etc. in 3D environments. Our goal is to see if this model can be used to validate the therapeutic efficiency of this nanozyme in the wound model and whether it can restore balance, reduce oxidative damage, and if it’s compatible with a 2D system or not. Industry Challenges: Why 3D Models Aren’t Mainstream Yet What is the industry getting wrong when it comes to developing and scaling 3D in vitro platforms for broader adoption by pharma or clinics? Dr. Jafari: One common issue is that when we talk about 3D in-vitro models, we often treat them as one thing, but there are many types, such as spheroids, organoids, hydrogel-based systems, bioprinted tissue models and organ-on-a-chip microfluidic devices. Each of them has strengths and limitations. At times, the industry treats them like interchangeable tools, but they really require different handling, materials, and validation. In my opinion, the major challenge is the lack of standard methods. There isn’t an agreed protocol on how to make 3D models–how long to culture the cells, or how to measure outcomes like viability, inflammation, or function. This makes it
3D Bone and Cartilage Models to Understand Tissue Regeneration
This month, we sat down with Dr. Johanna Bolander. Dr. Bolander has a PhD in Regenerative Medicine from K.U Leuven and a postdoc at the MERLN Institute of Technology in Maastricht, as well as the Wake Forest Institute for Regenerative Medicine in North Carolina. Currently, she is an Assistant Professor at Charité Hospital in Berlin, as well as a Principal Member of the Technical Staff at imec. Dr. Bolander is an expert in bone and cartilage tissue and uses 3D models to investigate why certain tissues fail to heal. Her joint positions give her the unique opportunity todevelop solutions from both a biological and technical perspective.
Ultra-Miniaturized Primary Hepatocyte Spheroids for Early-Stage Drug DiscoveryÂ
This month, we sat down with Dr. Brinton Seashore-Ludlow. Dr. Seashore-Ludlow has a PhD in organic chemistry and synthetic methods from The Royal Institute of Technology (KTH) in Stockholm and did a postdoc at the Broad Institute of Harvard and MIT. Currently, she is a Senior Researcher at Karolinska Institutet and the Chemical Biology Consortium of Sweden focusing on precision cancer medicine.
3D Models of the Most Communicative Organ in the Body: Fat
This month, we sat down with Dr. Elvira Weber, adipose tissue organoid pioneer, expert in regenerative medicine, and Head of Lab at the CURE 3D lab in DĂĽsseldorf. Â
The Key to Moving 3D Culture Forward
This month, we sat down with Dr. Maryna Panamarova, a technical expert in the 3D culture space. Dr. Panamarova is working to develop and upscale novel organoid models at the Wellcome Sanger Institute. She is an advocate for making knowledge open source and believes it’s key to advancing the industry forward.Â
A vision for animal-free drug testing with Dr. Tamara Zietek
This month, we sat down with Dr. Tamara Zietek, a pioneer in 3D intestinal modelling and a leading voice pushing for the replacement of animal testing in life science with New Approach Methodologies (NAMs). We discuss her journey, the evolution of in-vitro 3D models, regulatory hurdles, and how we can achieve a paradigm shift in drug development.Â
The need for standardization in 3D cell culture (let’s start small)
In the realm of 3D cell culture, the diversity of terminology – from organoids and tumoroids to spheroids and Microphysiological Systems (MPS) – reflects innovation but also creates barriers to communication and adoption.
5 benefits that 3D cell culture will bring to pharmaceutical drug development
Advances in 3D cell culture excite us — that’s why we got into this game. But what does it mean for the future of your healthcare?
