3D printing of cell-free implants: A promising avenue for cartilage regeneration and joint preservation (5/2026)

Abstract

Articular cartilage injury and osteoarthritis affect hundreds of millions worldwide, yet current treatments, from microfracture to autologous chondrocyte implantation, remain plagued by their limited efficacy. In this perspective, Zhou and colleagues argue for a transformative paradigm shift: moving beyond cell-based therapies toward 3D-printed cell-free implants that harness the body's intrinsic regenerative capacity.

The authors present a compelling case for leveraging endogenous stem/progenitor cells (ESPCs) through meticulously engineered biomaterial scaffolds. Unlike conventional approaches requiring costly in vitro cell expansion, these acellular implants are designed to actively recruit, retain, and guide resident stem cells toward functional cartilage and bone regeneration. By integrating precise biophysical cues (topography, stiffness, porosity) with biochemical signals (chemoattractants, growth factors, immunomodulatory agents), 3D printing enables patient-specific customization and spatiotemporal control unattainable with traditional manufacturing.

The article critically examines the biological mechanisms underlying endogenous regeneration, contrasts cell-free versus cell-based strategies, and navigates the complex translational pathway from bench to bedside. While challenges remain, including long-term stability, optimal cue combinations, and efficacy in aged or osteoarthritic joints, the convergence of advanced biomaterials, biofabrication technologies, artificial intelligence, and organ-on-a-chip technologies promises to accelerate clinical adoption.

This timely perspective challenges the assumption that exogenous cells are indispensable for cartilage repair, proposing instead that well-designed cell-free devices could democratize access to regenerative care. For the growing aging population affected by degenerative joint diseases, 3D-printed acellular scaffolds represent a cost-effective, scalable, and ethically advantageous pathway toward functional joint preservation and restored quality of life.