Cancer is a major global public health problem. It is of great significance for space tumor research to construct accurate tumor pathological models through space biopring-based 3D printing. Due to the adverse effects of environmental factors such as space microgravity, radiation, and strong vibration during the launch process on the forming effect and cell activity of space bio-3D printing, while the weight that satellites can carry is very limited, making the space 3D printing of living cell tissue models very difficult, and it is still in its infancy internationally.
In order to meet the above challenges, the research group of Xiong Zhuo and Zhang Ting from the Department of Mechanics of Tsinghua University has developed a complete set of spatial 3D printing and cultivation automation system for tumor models (total weight only 6 kg) after nearly three years of research. A temperature-sensitive bio-ink and suspension medium system suitable for space microgravity environment was developed, which has excellent biocompatibility, printing performance, room temperature storage and leak-proof characteristics, and effectively solved the problem of in-orbit printing and in-situ culture of tumor model samples. A two-color fluorescence microscope in situ automatic imaging technique based on deep learning algorithm was proposed, and a software system for automatic telemetry, control and analysis was designed to realize in-orbit printing, autofocus, fluorescence imaging and data return of tumor model samples.
FIG. 1 Pre-launch commissioning, installation and launch site
On June 7 this year, the tumor model space 3D printing and culture system developed by the team was successfully launched in Jiuquan Satellite Launch Center, and successfully completed the in-orbit test, creating a precedent for tumor model space 3D printing. According to the analysis of the returned data, it was found that the space microenvironment was conducive to the accurate printing and long-term morphology maintenance of three-dimensional tumor models, while enhancing the sensitivity of lung cancer cells to chemotherapy drugs, providing a new idea for future tumor treatment, and is expected to accelerate the development of space tumor medical research.
FIG. 2 In-orbit printing process and experimental results of 3D tumor model
Here, we developed a novel satellite-based 3D bioprinting device with high structural strength, small volume, and low weight (< 6 kg). We developed a microgel-based biphasic thermosensitive (MBT) bioink and suspension medium that supported the on-orbit printing and in situ culture of complex tumor models. We developed an intelligent control algorithm that enables the automatic control of 3D printing, autofocusing, fluorescence imaging, and data transfer back to the ground. To our knowledge, this is the first time that on-orbit printing of tumor models has been achieved in space with stable morphology and moderate viability via a satellite. We found that 3D tumor models were more sensitive to antitumor drugs in space than on Earth. This study opens up a new avenue for 3D bioprinting in space and offers new possibilities for future research in space life science and medicine.