3D bioprinting under extreme environments: Progress, opportunities, and challenges

With precise spatial control and patient-specific adaptability, 3D bioprinting has become a critical technology in tissue engineering, facilitating the reconstitution of cellular microenvironments and the improvement of tissue functionality. Conventional bioprinting is typically conducted under stable and controlled conditions, including constant temperature, normoxic atmosphere, normal gravity, and static platforms. In contrast, extreme-environment 3D bioprinting refers to bioprinting performed under conditions that deviate markedly from these norms. This emerging approach broadens the application range of bioprinting and creates new opportunities to study biological processes under extreme environments and to enable rapid tissue repair in challenging environments. Achieving stable and functional biomanufacturing under such conditions requires systematic optimization of printing strategies, bioink compositions, and equipment design. These elements must be adapted to environmental constraints while preserving structural fidelity and cell viability. At the same time, the distinct physical and biological effects of extreme environments may present exploitable advantages for enhancing tissue complexity and functional maturation. This review provides a comprehensive analysis of strategies for enabling 3D bioprinting in extreme environments. It further summarizes the unique advantages and emerging applications of biomimetic fabrication of tissues with complex structures and mechanical properties, replication of cellular biochemical microenvironments, and real-time biofabrication. Finally, it offers a forward-looking perspective on the key opportunities and challenges for biomanufacturing under extreme environments. Overall, this review outlines a roadmap for researchers and innovators in the field and provides insights into current advances and future directions.