MACROS · Magnetically Tunable Chondrocyte Cell Sheet Engineering for Osteoarthritis Therapy

Magnetically Tunable Chondrocyte Cell Sheet Engineering for Osteoarthritis Therapy

Background. Osteoarthritis (OA) is a major cause of disability and socioeconomic burden. It progressively destroys articular cartilage and reduces mobility and quality of life across all ages, including a large working-age population, while driving substantial direct (healthcare) and indirect (productivity) costs. Current regenerative options are limited. Cell injection (the benchmark) can help early OA but demands high cell numbers, suffers low retention/viability, and is expensive (~€15,000 per treatment). Cell-sheet therapy is emerging as a safer, more effective format because it preserves cell–cell and cell–matrix interactions, yet the standard temperature-responsive pNIPAM platform is far too stiff (2–3 GPa) and non-tunable, biasing chondrocytes toward fibrocartilage (type I collagen) rather than hyaline cartilage (type II collagen) needed for durable joint function. The overarching goal of this project is to deliver an innovative, magnetically tunable stiffness cell-sheet engineering platform that yields hyaline-like chondrocyte sheets with superior regenerative potential for early-stage OA, without adding exogenous bio-factors. Objectives (mapped to WPs): 1. WP1 – Magnetic-responsive substrate: Engineer a non-covalent based magnetic hydrogel enabling (i) robust monolayer formation and on-demand, gentle detachment into intact cell sheets; and (ii) in situ stiffness modulation by external magnetic fields. 2. WP2 – Dynamic stiffness control: Establish proof-of-concept that stiffening–softening cycles alter cell-sheet behavior in predictable ways (using stiffness-sensitive cells) and quantify cytoskeletal and mechano-transduction markers. 3. WP3 – Cartilage-mimicking chondrocyte sheets: Apply the dynamic protocol (stiffen for proliferation → soften for hyaline matrix deposition) and benchmark against pNIPAM sheets using immunostaining, gene expression, and CAG’s condyle chip assay for functional efficacy. Expected impacts of the project are: • Technical bottleneck removed: Replaces fixed, ultra-stiff pNIPAM with a tunable platform that matches chondrocyte mechanobiology, increasing the type II:type I collagen ratio and preserving a chondrogenic phenotype. • Clinical value: Cell sheets require approximately 10× fewer cells than injections for similar defect areas, enabling a 30–40% cost reduction (to around €10,000) and potentially broadening clinical accessibility. • Translational readiness: The approach eliminates the need for exogenous growth factors, simplifying safety and regulatory assessment; the gentle, stimulus-controlled detachment preserves cell viability and extracellular matrix (ECM) continuity. Pathway to impact is separate into three period dependents on the project period: Short term (project end): • Used the non-covalent cell sheet fabrication hydrogel platform with quantitative evidence of hyaline-like matrix enrichment and superior function in the condyle chip assay. Medium term (12–36 months post-project): • Exploitation with TUM/CAG: IP filing on dynamic stiffness and cell-sheet process; integration into CO.DON AG.s preclinical pipeline (including donor variability, safety, animal reduction via chip-based assays); early regulatory dialogue (EMA scientific advice) on ATMP classification, potency assays, and comparability. • Manufacturing & QA: Transfer of cell sheet fabrication platform and substrate fabrication to GMP-amenable workflows; definition of critical quality attributes (CQA) for stiffness, detachment yield, and ECM composition. Long term (3–6 years): • Clinical translation in early OA cohorts where joint-replacement is inappropriate: first-in-human feasibility, then controlled trials versus cell injection. • Economic and societal impact: Lower procedure costs, improved durability (targeting benefits beyond 5 years), reduced absenteeism, and productivity gains for Europe’s working-age population. The success on the impact of the project will be measured by the following criteria: • Scientific: First physical, factor-free dynamic-stiffness strategy for cell-sheet engineering; new insights into mechanical memory in chondrocytes; wider adoption of chip-based efficacy assays, accelerating OA research while reducing animal use. • Clinical: More durable symptom relief and function vs. cell injection, with better ECM quality and sheet integrity. • Economic: Projected 30–40% reduction in cell-related costs; pathway for a European SME/industry (CAG) to access the large OA market with an ATMP-compatible product, strengthening EU competitiveness. The success will be measured by the following criteria: • Benchmarks: ≥2× increase in type II:I collagen ratio vs. pNIPAM; ≥90% sheet viability post-detachment; reproducible stiffness switching (<0.4 T culture modulation; >0.5 T detachment). • Translation: The adoption of experimental results and protocol by CO.DON AG; in particular in the context of chondrocyte expansion, and transformation into cell sheet.

Data: CORDIS, © European Union