Organ-on-a-chip (OoC) systems are microfluidic technologies that replicate human physiology and disease conditions ex vivo, offering a promising alternative to animal models in preclinical drug testing and fundamental biological studies. Traditionally, OoCs systems are fabricated using conventional soft-lithography techniques with polydimethylsiloxane (PDMS) primarily due to its excellent inherent properties, including gas permeability, optical transparency, and biocompatibility. However, PDMS presents several notable shortcomings, most its limited scalability, which have prompted the search for more rapid and scalable fabrication processes. In this study, we present a cost-effective, efficient, and rapid design, development, and prototyping process for a microfluidic tumor-on-a-chip (TOC) platform technology for applications in cancer research and drug screening. Specifically, we present a novel 3D-printed, closed-system TOC device (i.e., Biochip) featuring distinct yet interconnected tumor and stromal regions, separated by an array of trapezoidal microposts, and fabricated with high precision and fidelity. The proposed Biochip was fabricated utilizing vat polymerization with a biocompatible resin and was compared alongside a conventional PDMS-glass (PDMS-G) and PDMS-laminate (PDMS-L) TOCs to evaluate its biological outcomes. The fabricated Biochip supported closed-channel 3D cell culture for testing up to 5 days. Using two triple-negative breast cancer cells (TNBC), namely SUM-159 and MDA-MB-231, we further assessed and cross compared cellular migration, viability, and morphology across the Biochip, PDMS-G, and PDMS-L platforms. Overall, this work establishes a 3D-printed Biochip as a robust, cost-effective, and time-saving alternative to PDMS-based OoC, and specifically TOC systems.

Current organoid culture systems face critical limitations: standardized growth factor formulations fail to capture patient-specific signaling requirements, while single-cell-type approaches overlook tumor-stromal interactions essential for understanding immunotherapy resistance. To address these challenges, we developed an automated biofabrication platform that systematically integrates patient-derived three-dimensional (3D) cultures with comprehensive growth factor profiling across 128 combinations. Through rigorous optimization of Matrigel concentration and gelation kinetics, we established standardized conditions achieving uniform signal distribution and quantitative reproducibility. Screening of 23 ovarian cancer patient samples identified universal growth factor combinations that consistently promoted robust cell growth while preserving parental tumor characteristics. Integration of growth factor response profiles with multi-scale genomic analysis revealed two estradiol-responsive cellular populations coordinating immunosuppression: a malignant cell fraction (MAL.PDCD5) that suppresses immune infiltration and a cancer-associated fibroblast fraction (FB.TNFSF10) that promotes immune exclusion through enhanced TGF-β signaling. Spatial transcriptomic validation demonstrated striking mutual exclusivity between FB.TNFSF10 cells and T/NK cells in native tissue architecture. Most significantly, FB.TNFSF10 abundance emerged as a robust predictor of immune checkpoint inhibitor therapy resistance across multiple cancer cohorts, independent of conventional biomarkers. This biofabrication platform provides a scalable, reproducible framework with broad applicability beyond oncology. The systematic optimization methodology is readily adaptable to other tissue types, disease models, and high-throughput drug screening applications, representing a significant advancement in functional tissue engineering for precision medicine.

The large-scale production of mammalian cells, particularly stem cells for clinical applications, remains challenging with existing cell culture technologies such as 2D cell culture flasks or 3D stirred tank bioreactors. Current methods have issues such as excessive cell aggregation and significant shear stress-induced cell death, resulting in low cell yield, unacceptable batch-to-batch variation, high production costs, and difficulties in scaling up. We hypothesize that creating a cell-friendly microenvironment that has efficient mass transport and minimized shear stress can enhance cell culture efficiency. In this study, we developed a novel hydrogel tube microbioreactor using collagen proteins (ColTubes) to test this hypothesis. First, we designed an innovative micro-extruder for fabricating ColTubes loaded with cells. Our results show that collagen proteins form a dense and robust nanofiber network capable of shielding cells from hydrodynamic stress while maintaining cell mass below 400 µm in diameter. The tube shell contains abundant nanopores that allow the cell culture medium to permeate and nourish the cells. Additionally, the collagen fibers serve as a substrate for cell adhesion. We show that ColTubes support high cell viability, rapid expansion, and impressive volumetric yields, offering substantial improvements over current methods. To our knowledge, ColTubes is a novel approach that has not been previously reported for cell manufacturing. ColTubes represents a scalable, cost-effective, and efficient solution for large-scale cell production.

Replicating the complex mechanical and biological properties of native tissues remains a key challenge in 3D bioprinting due to the limitations of single-nozzle systems. Here we present a multi-nozzle alternating bioprinting platform that addresses these problems by enabling precise control of mechanical and bioactive components' composition and distribution. By alternating cell-laden bioinks with mechanically reinforcing inks, our method enables precise spatial control for fabricating complex, anisotropic tissue architectures. A tri-layer printing strategy, using heart valve leaflets as a demonstrative model, was developed. In detail, gelatin methacryloyl (GM) bioinks, incorporating with porcine aortic valve interstitial cell (VIC) and bioactive substances (e.g., basic fibroblast growth factor (bFGF), polyaspartic acid (PASP), or chondroitin sulfate (ChS)) to support cell function, are alternated with poly (ethylene glycol)-blockpoly (propylene glycol)-block-poly (ethylene glycol) (F127) diacrylate (FD) mechanical reinforcement inks. This approach enhanced mechanical integrity of the constructs while supporting collagen, proteoglycan, and elastin production. Crucially, the constructs' mechanical robustness allowed direct cyclic mechanical stimulation during culture, further promoting tissue maturation and extracellular matrix (ECM) remodeling. In vivo, the constructs showed excellent biocompatibility, with minimal calcification and favorable immune responses. This multi-material bioprinting platform enables the fabrication of tissue models that meet both structural and functional requirements, and can be adapted for a wide range of heterogeneous tissue and organ engineering applications, with the potential to significantly advance regenerative medicine.

The transplantation of human bone marrow mesenchymal stem cells (hMSCs) exhibits promising therapeutic effects in the treatment of myocardial infarction (MI), however, its clinical application is limited due to the low survival rate of the transplanted cells. Three-dimensional (3D) bioprinted tissue engineering patches have demonstrated efficacy as a delivery approach to enhance the viability and engraftment of stem cells. In this study, we have developed a novel hMSCs tissue-engineered patch equipped with a nano-slow-release system using 3D bioprinting technology. The patch is based on a matrix material consisting of methacrylated gelatin (GelMA) and chitosan nanoparticles loaded with vascular endothelial growth factor (VEGF), which possesses pro-angiogenic effects. The resulting patch demonstrated excellent compatibility with hMSCs and enabled stable, sustained VEGF release.results showed that the patch significantly reduced cardiomyocyte apoptosis three days after MI, and improved cardiac function and myocardial fibrosis at 28 d post-surgery. These effects were closely associated with the patch's potent angiogenic properties and favorable stem cell survival. In conclusion, this study successfully developed a 3D-printed tissue engineering patch with strong potential for clinical application, offering a promising new approach for the treatment of MI.

3D bioprinting enables rapid fabrication of complex biological structures for tissue engineering applications. However, optimizing bioink formulation remains challenging due to complex relationships among material properties, printability, and cell viability. While the perimeter ratio (Pr) is commonly used to evaluate printability, it cannot adequately capture the full geometric fidelity required for comprehensive printability assessments, limiting robust bioink design. To address this limitation, a novel Hausdorff distance (HD) metric is employed to quantify printability, directly measuring the maximum deviation between the designed and printed structures. Furthermore, multiple machine-learning approaches were applied to alginate-hyaluronic acid (ALG-HA) composite inks and rat pheochromocytoma-derived PC12 cells to assess printability and cell viability. Rheological parameters were characterized using support vector regression (SVR) with R² ≥ 0.974. Multi-layer perceptron (MLP) regressors achieved R² values of 0.932 and 0.945 when predicting HD values of printed grid structures and cell viability, respectively. A regression-based convolutional neural network (CNN) was developed to predict HD values directly from grid structure images, achieving an R² of 0.986. Through optimization, optimal as-extruded cell viability (≥ 95%) can be achieved while maintaining high printability (HD ≤ 0.20). The optimal ink composition was further verified with good long-term cell viability and proliferation potential. This proposed AI-integrated approach can dramatically reduce ink optimization time by rapidly predicting rheological properties, printability, and cell viability from minimal experimental data.

Bottom-up tissue engineering has gained significant interest for its ability to recreate the complexity of human organs by assembling functional tissue units through techniques such as extrusion-based bioprinting (EBB). To enable the future biofabrication of human-scale organs, new bioinks for EBB must be developed that facilitate the formation of a functional vascular network within the biomaterial. Without a vascular system, high cell densities within the construct struggle to survive due to the diffusion limits of oxygen and nutrients. Additionally, the bioink must exhibit sufficient printability to accurately recreate the 3D CAD model. In the current work, elastin is modified with norbornene groups to enable step-growth polymerization with thiolated gelatin, resulting in a novel hybrid biomaterial. Unmodified gelatin and porogens are incorporated into the elastin-gelatin hydrogel to enhance printability in EBB and increase porosity, respectively. When only unmodified gelatin is added to the elastin-gelatin hydrogel, shape fidelity on a continuous platform is excellent, and the bioink successfully bridges gaps up to 8 mm with a 100% success rate. Upon addition of alginate gel porogen (AGP), quality of printing on a continuous platform is maintained, but the gap-bridging capability becomes limited to gaps smaller than 4 mm. Nonetheless, the elastin-gelatin hydrogel supplemented with both unmodified gelatin and AGP is preferred, as it promotes superior vascular development compared to a wide range of other bioinks, with vasculogenesis-driven self-assembly of embedded endothelial cells reaching a total vascular network length of 26 ± 6 mm mmand angiogenic sprouting from vascularized spheroids reaching a total sprout length of 4 ± 2 mm within the hydrogel by day 7. A bioink that supports this level of vascular development while maintaining sufficient printability represents a valuable addition to the toolkit for bottom-up tissue engineering using EBB.

Three-dimensional (3D) bioprinting is an emerging strategy for constructing tissues and organs in vitro. Here, we achieved long-term expansion of primary mouse hepatocytes using a defined medium and constructed liver tissue using 3D bioprinting. The 3D-printed liver tissue demonstrated several essential liver functions and was able to prolong the survival of mice with acute liver failure due to extreme hepatectomy after in vivo transplantation, and the transplanted artificial liver tissue showed distinct functional partitioning. Overall, our results develop a method for long-term in vitro culture of primary hepatocytes and demonstrate the potential of 3D bioprinted liver tissue for clinical translational applications.

Smooth muscle cells (SMCs) derived from induced pluripotent stem cells (iPSCs) have been used for scaffold-free structures; however, their use in regenerated organs is rare and not well established. The induction of mesenchymal stem cells (MSCs) via neural crest cells (NCCs) from iPSCs offers advantages such as a large-scale cell stock. While research has progressed on the chondrogenic differentiation and regenerative medicine applications of cartilage derived from human iPSC-derived MSCs via a NCCs lineage (iNC), studies on smooth muscle, a critical tracheal component alongside cartilage, remain limited. In this study, we aimed to establish a method for generating airway smooth muscle tissue constructs using human iNCMSCs, assess their contractile function, and evaluate their regenerative potential in tracheal cartilage defects. iNCMSCs were cultured for 28 d in Dulbecco's Modified Eagle Medium (DMEM) with fetal bovine serum (FBS), with one group receiving transforming growth factor beta 1 (TGF1, DMEM-TGF1 group) and the other group without TGF1 (DMEM group). SMCs markers was assessed using immunofluorescence staining. The tissue constructs were bio-3D printed using spheroids from the DMEM-TGF1 group and transplanted as smooth muscle patches into full-thickness defects in the rats' tracheas. The DMEM-TGF1 group showed strong expression of SMCs markers such as-smooth muscle actin, calponin, and myosin heavy chain. After 28 d post-transplant, histological evaluation confirmed graft engraftment, adequate blood flow, and epithelial layer extensions from the recipient tissues, along with well-maintained tracheal structures. This study demonstrated the feasibility of using iPSC-derived iNCMSCs to generate bio-3D printed smooth muscle constructs for tracheal regeneration. Our findings support the potential of this strategy as a novel approach for airway reconstruction, offering a scaffold-free cell-based platform for future clinical applications in tissue engineering for airway regeneration.

The next generation of three-dimensional (3D) micro-additive manufacturing (AM) bioelectronics requires inks that simultaneously combine high electrical conductivity, biocompatibility, electrochemical stability, and compatibility with 3D processing. However, most existing inks fail to meet all these criteria, with processability and repeatability remaining major bottlenecks. This challenge is particularly serious in printed electronics technologies, such as Aerosol Jet® Printing (AJ®P), for which commercially available formulations tailored to specific applications are still scarce. Here, we present a novel poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS)-based ink incorporating polyethylene glycol, ethylene glycol, and carboxymethyl cellulose to obtain a composite that fulfils all requirements, being conductive, processible by AJ®P and biocompatible. The formulation exhibits high conductivity (= 495.29 S · cm), electrochemical stability, and biocompatibility with both human fibroblasts and iPSC-derived neural stem cells. Its low viscosity (= 7.93 mPa · s) enables precise and repeatable AJ®P fabrication while supporting controlled, high-resolution 2D patterning and 3D microfabrication with aspect ratios up to 9. Dense or hollow microarrays of 24 flexible pillars (diameter ⩾ 35m; elastic modulus = 3.1 × 10Pa per pillar) can be fabricated within 10 min, without masks or supporting materials. This work focuses on the material and process optimisation study of a customisable bioink for AJ®P in 3D micro-AM bioelectronics, with potential applications in 3D microelectrode arrays, biosensors, tissue engineering.

Developing a biomimetic culture system is crucial for the efficient maintenance and expansion of rare hematopoietic stem and progenitor cells (HSPCs). This advancement can significantly enhance the application of HSPC-based transplantation therapies and support the manufacturing of bone marrow (BM) organoids. Traditional two-dimensional culture systems fall short in replicating the interactions between cultured cells and the hematopoietic niche, resulting in excessive reactive oxygen species (ROS) production and triggering HSPC differentiation. In response, we have developed an innovative three-dimensional (3D) culture system using a novel composite hydrogel, GelMA-PVA-TSPBA (GelMA-P-T), which offers excellent biocompatibility and ROS-scavenging properties. When murine and human embryonic stem cell (hESC)-derived HSPCs were cultured in this new hydrogel, they exhibited low ROS levels and showed enhanced self-renewal and expansion capabilities. Importantly, incorporating niche-related cells into the composite hydrogel created a 3D engineered BM microenvironment that significantly improved the self-renewal and expansion of HSPCs. Additionally, the biomimetic niche comprising GelMA-P-T and various stromal cells effectively inhibited the differentiation of murine and hESC-derived HSPCs. Mechanistically, compared with GelMA, the low ROS microenvironment fostered by GelMA-P-T significantly enhanced mitochondrial function in HSPCs, supporting the expression of HSPC-related genes and inhibiting blood cell differentiation. Our findings suggest that the GelMA-P-T-based biomimetic culture system has the potential to advance the clinical application of expanded HSPCs and accelerate the development of BM organoid technology.

Bone metastases account for the majority of deaths from breast cancer (BCa) and produce painful osteolytic lesions through osteoclast hyperactivation. However, the reciprocal interaction between BCa cells and the metastatic bone niche in regulating the osteolytic process remains largely unknown. Therefore, we examined the effect of bone microenvironmental cues on the acquisition of osteomimetic features (expression of bone-cell markers to bypass immune monitoring) by MDA-MB-231 triple-negative BCa cells. Four different hydroxyapatite (HA) particles in the micron size range (3-25m) with varying physiochemical characteristics were combined with type I collagen matrix. This produced composites to emulate the secondary bone metastasis niche at the bone marrow-cortical bone interface we termed the 'bone bioengineered interfaces' (BBIs). We showed that passive calcium dissolution from HA crystals in the BBIs is a critical bio-determinant related to MDA-MB-231 cells' osteomimicry and osteoclastogenesis of THP-1 monocytic cells in bone metastasis. These findings provide novel insights into the mechanisms of the reciprocal interaction between BCa cells and the metastatic bone microenvironment and pave the way for the potential use of more effective and environmentally friendly approaches for personalised medicine platforms and tailored therapeutic strategies.

Peptides are essential bioactive compounds with broad applications in nutraceuticals, pharmaceuticals, cosmetics, and materials. As their applications continue to grow, the development of efficient and sustainable synthesis methods has emerged as a major focus of research. This review provides a comprehensive summary of the primary methods for peptide synthesis, including biosynthesis, classical solution-phase peptide synthesis (CSPS), solid-phase peptide synthesis (SPPS), liquid-phase peptide synthesis (LPPS), and emerging technologies such as transition metal catalysis, photocatalysis, and electrochemistry. Special emphasis is placed on the recent advancements in CSPS, SPPS, LPPS, and emerging technologies, with a particular focus on the integration of green chemistry principles into SPPS and emerging techniques. These methods not only involve the construction of peptide molecules but also the conversion of linear peptides into cyclic peptides. Through an in-depth review of the relevant literature, this paper outlines the fundamental principles, advantages, and limitations of each method, while exploring their potential to enhance synthesis efficiency, reduce production costs, and minimize environmental impact. This study aims to explore innovative pathways in peptide synthesis, drive its applications in biomedicine and materials chemistry, and advocate for the deep integration of green and sustainable principles into research and practice.

The growing demand for physiologically relevant human brain models has driven the development of advanced three-dimensional (3D) systems that can recapitulate key aspects of neural architecture and function. Traditional two-dimensional cultures and animal models fall short in reproducing the structural complexity, cellular diversity, and species-specific characteristics of the human central nervous system. In this review, we provide a comprehensive overview of state-of-the-art scaffold-free and scaffold-based strategies for generating 3D human brain models, with particular emphasis on those derived from pluripotent stem cells. Scaffold-free systems-such as spheroids, organoids, and assembloids-exploit the intrinsic self-organizing capacity of neural cells to recreate spatially and temporally regulated interactions observed during development. Conversely, scaffold-based models utilize biomaterials, including hydrogels and decellularized matrices, to replicate the physical and biochemical properties of the brain microenvironment, providing enhanced control over tissue architecture and reproducibility. A wide range of fabrication methods is discussed, and for each, we assess key features, strengths, and limitations, with particular attention to scalability, reproducibility, and biological relevance. Overall, this review is intended to serve as a practical and well-structured reference for researchers seeking to select or develop the most appropriate3D brain model for specific applications in neural development and disease modelling.

The fabrication of anatomically accurate, cellularized heart valve substitutes remains a significant challenge in tissue engineering, particularly for pediatric and patient-specific applications. While three-dimensional (3D) bioprinting enables the creation of complex geometries, it often compromises cell viability and lacks the precision required for small-scale constructs. In this study, we present a high-fidelity, reproducible molding technique using 3D-printed sugar glass molds to engineer custom, alginate-based hydrogel cellularized heart valves. Human adipose-derived stromal cells (ASCs) were used as the cell source due to their accessibility and regenerative potential. This approach overcomes the limitations of conventional molding and bioprinting by enabling the reproduction of intricate anatomical features, including the sinuses of Valsalva, which are critical for physiological hemodynamics. The molding method maintains high cell viability (>90%) at the time of fabrication and the process supports both scalability and automation. Sugar glass molds for valve sizes from 16 to 26 mm inner diameter were printed with 90% of the mold surface within a ±0.3 mm deviation of the reference computer-aided design model. Cellularized valves cultured in a custom perfusion bioreactor retained structural integrity and cell viability over a 14 d period. This biofabrication strategy offers a promising platform for engineering patient-specific heart valves and also lays the groundwork fordisease modeling, including valve mineralization, using living cells such as ASCs.

Bioprinting, a technology with the potential to support long-term space missions, offers medical solutions for human settlements on the Moon and Mars. Moreover, 'green bioprinting' presents a promising approach to address terrestrial environmental challenges. Effective and cost-efficient implementation of this technology beyond the Earth requires leveragingresources on celestial bodies. Consequently, this study examines the integration of Lunar and Martian regolith into bioprintable hydrogels as mechanically stabilizing and protective components as well as nutrient sources. Hydrogel blends composed of alginate and methylcellulose were supplemented with regolith simulants. Rheological characterization revealed maintenance of shear thinning and shear recovery properties, ensuring optimal printability. In regards to cultivation of microalgae, the ion release/uptake of the regolith simulants in culture medium was investigated, indicating that regolith has potential to serve as nutrient source. The microalgaand bacteria. MASE-IM-9 andwere bioprinted in regolith-based inks. Results demonstrate that the microalgae maintained their photosynthetic efficiency in regolith-containing bioinks during cultivation, exhibiting high viability and growth. The bacteria exhibited an enhanced resistance to desiccation as well as temperature and radiation stress when regolith simulants were present in the hydrogels. This study confirms the feasibility of employing Lunar and Martian regolith simulants in bioinks for green bioprinting and bacterial bioprinting. Such an approach could minimize the volume of stored printing materials and culture media, optimizing rocket transport capacity.

Liposomes, as one of the most promising and rapidly evolving drug delivery systems, are highly valued for their biocompatibility, ability to encapsulate diverse drugs, controlled release, and targeted delivery, offering enhanced therapeutic effects with reduced toxicity. However traditional methods for synthesizing liposomes still exhibit problems such as uncontrollable particle size and uneven distribution, reducing passive targeting efficiency and compromising treatments In present study, we introduce a novel alternating current electrokinetic mixing-assisted micro-synthesis method for liposome production, utilizing a novel custom (mold-extraction) approach to fabricate a 3D-structured microfluidic chip with parallel electrodes along both sides of the channel. Unlike traditional methods, where etched thin electrodes often result in non-uniform electric fields and leakage, the present method enables the placement of 3D electrodes with channel thickness, minimizes electrode distance, and allows for the generation of a strong, uniform electric field at low voltages. Consequently, controllable ultra-fast active mixing is achieved, resulting in the controlled and adjustable synthesis of liposomes with uniform size distributions. The effects of flow rate,(electric field intensity), and frequency on the synthesis of liposomes were investigated. Additionally, studies demonstrated that drug encapsulation efficiency can be precisely controlled by modulating the applied electric field, a capability that was further validated through cellular experiments. This study presents a straightforward and adjustable approach for the precise synthesis of liposomes, which can be utilized to develop customized drug delivery systems.

Hydrogels are widely used in tissue engineering but conventional homogeneous polymerization often creates dense matrices that hinder cell migration and restrict extracellular matrix production. The motivation of this project was to overcome these limitations by developing a heterogeneously crosslinkable hydrogel platform that enables both cell migration and matrix deposition. We present a two-step heterogeneous polymerization approach that introduces spatial variations in matrix density, producing tunable, cell-sized pores that promote migration, proliferation, and matrix synthesis. As an implementation, gelatin was pre-assembled into microribbon-like building blocks using a Dynamic Molding process, methacrylated to introduce crosslinkable groups, chemically modified, washed, and freeze-dried. Upon rehydration, the ribbons formed a moldable paste that could be mixed with cells and photo-crosslinked into scaffolds with in situ-formed, cell-sized pores. The main novelty of this method is the introduction of chemical modifications with methacrylic anhydride (MAA), acetic anhydride (AceA), and succinic anhydride (SucA), which enable a controlled two-step heterogeneous polymerization and allow independent tuning of scaffold microstructure, mechanics, and degradation. AceA reduced crosslink density and accelerated degradation, whereas SucA promoted swelling, enhanced mechanical strength, and slowed degradation. Cell studies revealed that SucA-modified scaffolds supported superior adhesion and proliferation compared to AceA-modified and unmodified controls. Such work may significantly impact the design of next-generation scaffolds by providing a versatile platform that integrates structural, mechanical, and biochemical control for regenerative medicine applications.

Triple-negative breast cancer (TNBC) is an aggressive subtype with limited treatment options. TAS-115, a multi-receptor tyrosine kinase inhibitor, has not previously been evaluated in TNBC. Here, we investigated its therapeutic effects alone and in combination with doxorubicin (DOXO), using 3D heterotypic spheroid models, including free-standing, bioprinted static, and perfused systems. TAS-115 significantly reduced cell proliferation and viability, enhanced apoptosis, and suppressed c-MET/HGF and PI3K/Akt/mTOR signaling. Combined treatment with DOXO further amplified these effects. In perfused bioprinted models, TAS-115 markedly inhibited tumor cell migration, highlighting its potential to limit metastatic behavior. These findings identify TAS-115 as a promising therapeutic strategy for TNBC, either as a monotherapy or in combination with chemotherapy.

Osteochondral defects are injuries generally affecting to the surface of hyaline cartilage and progressing throughout the tissue until the underlying subchondral bone. The osteochondral unit is a multizonal tissue in which cells within each layer have a specific phenotype arising from their differential maturation stages; persistent, proliferative and hypertrophic chondrocytes in the superficial, middle and deep zones of cartilage, respectively, and osteoblast in the subchondral bone. These distinct cells regulate the composition of their microenvironment through sensing the surrounding physicochemical properties, where topography plays a crucial role. Tissue regeneration appears as a great alternative to promote the formation of a durable and functional osteochondral unit, where distinct parameters such as the biomaterial chemistry, mechanical properties or topography can be adjusted to match the native tissue. However, current approaches focus mainly on tuning the first two parameters, omitting the inclusion of topography. Moreover, only few have considered the inclusion of topography on scaffolds and investigated their effect in preclinical studies; number that is further reduced when reaching clinical trials. This review summarizes the state of the art in the regeneration of the osteochondral unit through the exploitation of topographical cues, setting into context relevant biological aspects, such as cell adhesion and proliferation, phenotype and deposition of zone-specific extracellular matrix that lead to the formation of a functional tissue.