(C-91) High-throughput aspiration-assisted bioprinting for scalable fabrication of human tissues

Introduction:: Bioprinting is a promising technology for tissue engineering and regenerative medicine; however, current approaches face critical limitations in achieving physiologically relevant cell densities, mimicking native tissues. To circumvent the challenges, this study introduces a novel technology called high throughput aspiration-assisted bioprinting with a digitally controlled nozzle array (DCNA) platform. The DCNA platform enables rapid bioprinting of spheroids with precise positioning, high throughput, minimized operation processes, and reduced manual interventions. As proof of concept, we propose a regenerative strategy for craniomaxillofacial (CMF) defects through intraoperative bioprinting, where patient-specific bone grafts are bioprinted using miRNA-transfected osteogenically-committed bone spheroids and the DCNA platform.

Materials and Methods:: The DCNA platform consists of X, Y, and Z motion axes for 3D movement, cameras, and a configurable array of 30G nozzles. Selective control of individual nozzles was achieved through solenoid valves and pressure/vacuum sensors in customized software. Spheroids were selectively loaded onto the nozzles and released at designated positions using the DCNA platform. Intraoperative bioprinting involves a hybrid process integrating extrusion-based bioprinting (EBB) and the DCNA platform. Two 5 mm critical-sized calvaria defects on the parietal bone of immunodeficient RNU Nude Rats (12-week-old, male/female) were created. The EBB was used to deposit a gel substrate for spheroid placements and promote bone regeneration of bioprinted spheroids. The DCNA precisely bioprinted two different densities (low-16 and high-64) of spheroids onto the defect area.

Results, Conclusions, and Discussions:: The DCNA platform demonstrated its ability to pick and pattern multiple types of spheroids simultaneously by controlling the aspiration pressure. It significantly reduced bioprinting time compared to conventional systems, allowing for the precise bioprinting of approximately 100 spheroids in less than 5 minutes. In a clinical setting, miRNA-transfected osteogenically-committed bone spheroids were successfully bioprinted onto rat calvaria defect sites in less than 5 minutes per defect. The DCNA bioprinted spheroids exhibited homogeneous bone regeneration throughout the defect area and better bone volume to total volume ratio compared to other groups (blank, ink only, and low density of spheroids). The intraoperative bioprinting of the DCNA platform facilitated the fabrication of patient-specific and defect-specific constructs for CMF regeneration.

This study presents a high-throughput bioprinting platform, enabling the fabrication of scalable tissue structures in a high-throughput manner. The DCNA platform significantly improves bioprinting performance compared to conventional bioprinting techniques. Due to the rapid bioprinting process of the DCNA platform, intraoperative bioprinting of spheroids was achieved with homogeneously and significantly regenerated CMF defects, marking a significant advancement in the field of bioprinting. These advancements have implications for personalized treatments and clinical translation in regenerative medicine, extending beyond bone regeneration to other functional tissue fabrication, organoid sciences, and drug/disease modeling.


Acknowledgements (Optional): :

This work has been supported by National Institutes of Health Award R01EB034566.

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