The results of the 2022 International Exhibition of Inventions Geneva were announced online on March 28th (Swiss local time). Forty-one teams from Tsinghua University won a total of 45 awards: 20 gold awards, 23 silver awards, and 2 bronze awards. This is a record high for our university. Inventions from Professor JIN Xin and Associate Professor MA Shaohua’s teams from Tsinghua SIGS were awarded gold at the event.
Prof. JIN Xin’s team’s award-winning invention is a time-of-flight-based volumetric scattering imaging system.
Team members
Volumetric scattering media widely exist in nature, such as fog, smoke, turbid water, biological tissue, etc. It seriously limits visibility and affects our daily life. Imaging within such volumetric scattering scenarios is extremely challenging since the signal photons that carry object information are dramatically attenuated and highly coupled with the background photons reflected by the scattering media. In this case, existing de-scattering methods, such as imaging enhancement, time gating, and inverse transmission modeling methods, fail to work under such strong scattering scenarios.
Professor JIN Xin and her team members DU Dongyu, DENG Rujia and KANG Jinshi have invented a time-of-flight-based volumetric scattering imaging system, which can reconstruct the complex objects embedded in the highly volumetric scattering media. The proposed method accurately models the spatial-temporal transmission of the scattered light and treats the mapping between scattered measurements and objects as a time-to-space migration of the scattered field. It outperforms related methods in terms of reconstruction precision and scattering strength. As shown in the following figure, the image captured by the traditional camera gives almost no useful information, while the proposed method provides a legible result. The imaging capability of the proposed system exceeds that of the human eye by more than 8 times. Additionally, the proposed method provides low reconstruction complexity and millisecond-scale runtime, which significantly benefits its practical applications for self-driving cars in extreme weather, non-destructive testing through packaging, medical imaging, and underwater exploration.
Experimental Results
System prototype and experimental scenario
Prof. MA Shaohua’s award-winning project is a high-throughput and automated tumor organoid platform which can be applied to formulate precision medical treatment for tumor patients and provide individualized medication guidance. It can also be used to discover and develop new anticancer drugs.
MA Shaohua’s team
Cancer ranks as the leading cause of death. In 2020, 19.3 million new cancer cases and 10.0 million cancer deaths occurred worldwide. Organoids are one of the most popular scientific ways to rebuild an effective tumor model. Compared with patient-derived xenografts, organoids have the advantages of low cost, fast and human genetic modeling, and suit individualized development.
Although organoids have been studied for many years, traditional organoids cannot form standards in either production or drug testing uses. They have the following disadvantages: small size, inconsistent cell composition, lack of tumor feature recapitulation, and high cell consumption. Further, it takes 4-6 weeks to grow them into mature models, or primary tissue culture that loses patient phenotype, etc.
A translational organoid platform can form standardized organoids with the following advantages: automation, high-throughput, tailorable size, shape, and composition, rapid production, and straight modeling from a patient’s tumors without primary culturing.
Schematic of automated high-throughput human organoid platform, organoid printer and 3D fluorescence staining image of patient-derived tumor organoid
Herein, the team developed an automated, high-throughput organoid platform that operates as follows: after obtaining a human tumor tissue, cells are extracted by machine milling and enzymatic reaction on the materials. Then the tissue-derived cells are suspended in Matrigel solution. Afterward, the cell suspension is injected into a microfluidics system to be formulated into uniform cell-laden Matrigel droplets. The droplets are gelated to become uniform organoid precursors. The precursors are then printed into a 96-well plate, or a customized chip for organoid culture. Each well contains one organoid precursor that is located exactly in the center of the well, to benefit imaging-based characterization during culturing. These organoid precursors are maturated within 1 week and ready for drug testing. As we can see from the prototype of our printing machine pictured above, the droplet formation and organoid precursor printing are synchronized and sequenced. The precision printing of individual organoids is further strengthened by a high-speed camera that can recognize an organoid approaching the printing nozzle, via a computer vision program.
In short, the organoid platform offers an automated and high-throughput solution for personalized organoid production and manipulations. It shortens the organoid modeling time from one month to one week, and increases the organoid production spectrum by over 10 times. The organoid products are better because they recapitulate the microenvironmental cells, including fibroblasts and immune cells. They are highly reproducible and consistent and can be standardized for industrial uses.
The team was led by Prof. MA Shaohua, who is also a faculty member at Tsinghua-Berkeley Shenzhen Institute (TBSI). His team is comprised of four graduate students and two employees from Tsinghua. The team includes talents in biology, mechanical and electronic engineering, and management.
The International Exhibition of Inventions of Geneva was founded in 1973 and is held once a year. It was not held in 2020 due to the COVID-19 epidemic. To date 2022, a total of 47 exhibitions and two online special editions have been successfully held.
The event is jointly hosted and organized by the Swiss Federal Government, the governments of the canton and city of Geneva, and the World Intellectual Property Organization. This annual exhibition is one of the oldest, largest, and most well-known invention exhibitions around the world.
Source: Tsinghua News & Professors JIN Xin and MA Shaohua’s research teams
Edited by Alena Shish & Yuan Yang
Cover photo by Wu Chen
