Engineering functional tissues and organs remains a fundamental pursuit in bio‐fabrication. However, the accurate constitution of complex shapes and internal anatomical features of specific organs, including their intricate blood vessels and nerves, remains a significant challenge. Inspired by the Matryoshka doll, here a new method called “Intra‐Embedded Bioprinting (IEB)” is introduced building upon existing embedded bioprinting methods. a xanthan gum‐based material is used which served a dual role as both a bioprintable ink and a support bath, due to its unique shear‐thinning and self‐healing properties. IEB's capabilities in organ modeling, creating a miniaturized replica of a pancreas using a photocrosslinkable silicone composite is demonstrated. Further, a head phantom and a Matryoshka doll are 3D printed, exemplifying IEB's capability to manufacture intricate, nested structures. Toward the use case of IEB and employing an innovative coupling strategy between extrusion‐based and aspiration‐assisted bioprinting, a breast tumor model that included a central channel mimicking a blood vessel, with tumor spheroids bioprinted in proximity is developed. Validation using a clinically‐available chemotherapeutic drug illustrated its efficacy in reducing the tumor volume via perfusion over time. This method opens a new way of bioprinting enabling the creation of complex‐shaped organs with internal anatomical features.
Engineering functional human tissues in vitro is currently limited by difficulty replicating the small caliber, complex connectivity, cellularity, and 3D curvature of the native microvasculature. Multiphoton ablation has emerged as a promising technique for fabrication of microvascular structures with high resolution and full 3D control, but cellularization and perfusion of complex capillary‐scale structures has remained challenging. Here, multiphoton ablation combined with guided endothelial cell growth from pre‐formed microvessels is used to successfully create perfusable and cellularized organ‐specific microvascular structures at anatomic scale within collagen hydrogels. Fabrication and perfusion of model 3D pulmonary and renal microvascular beds is demonstrated, as is replication and perfusion of a brain microvascular unit derived from in vivo data. Successful endothelialization and blood perfusion of a kidney‐specific microvascular structure is achieved, using laser‐guided angiogenesis. Finally, proof‐of‐concept hierarchical blood vessels and complex multicellular models are created, using multistep patterning with multiphoton ablation techniques. These successes open new doors for the creation of engineered tissues and organ‐on‐a‐chip devices.
more » « less- NSF-PAR ID:
- 10451682
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Healthcare Materials
- Volume:
- 10
- Issue:
- 10
- ISSN:
- 2192-2640
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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