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Abstract Simultaneous longitudinal imaging across multiple conditions and replicates has been crucial for scientific studies aiming to understand biological processes and disease. Yet, imaging systems capable of accomplishing these tasks are economically unattainable for most academic and teaching laboratories around the world. Here, we propose the Picroscope, which is the first low-cost system for simultaneous longitudinal biological imaging made primarily using off-the-shelf and 3D-printed materials. The Picroscope is compatible with standard 24-well cell culture plates and captures 3D z-stack image data. The Picroscope can be controlled remotely, allowing for automatic imaging with minimal intervention from the investigator. Here, we use this system in a range of applications. We gathered longitudinal whole organism image data for frogs, zebrafish, and planaria worms. We also gathered image data inside an incubator to observe 2D monolayers and 3D mammalian tissue culture models. Using this tool, we can measure the behavior of entire organisms or individual cells over long-time periods.
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Nondestructive, longitudinal, 3D oxygen imaging of cells in a multi-well plate using pulse electron paramagnetic resonance imaging
Abstract The use of oxygen by cells is an essential aspect of cell metabolism and a reliable indicator of viable and functional cells. Here, we report partial pressure oxygen (pO2) mapping of live cells as a reliable indicator of viable and metabolically active cells. For pO2imaging, we utilized trityl OX071-based pulse electron paramagnetic resonance oxygen imaging (EPROI), in combination with a 25 mT EPROI instrument, JIVA-25™, that provides 3D oxygen maps with high spatial, temporal, and pO2resolution. To perform oxygen imaging in an environment-controlled apparatus, we developed a novel multi-well-plate incubator-resonator (MWIR) system that could accommodate 3 strips from a 96-well strip-well plate and image the middle 12 wells noninvasively and simultaneously. The MWIR system was able to keep a controlled environment (temperature at 37 °C, relative humidity between 70%–100%, and a controlled gas flow) during oxygen imaging and could keep cells alive for up to 24 h of measurement, providing a rare previously unseen longitudinal perspective of 3D cell metabolic activities. The robustness of MWIR was tested using an adherent cell line (HEK-293 cells), a nonadherent cell line (Jurkat cells), a cell-biomaterial construct (Jurkat cells seeded in a hydrogel), and a negative control (dead HEK-293 cells). For the first time, we demonstrated that oxygen concentration in a multi-well plate seeded with live cells reduces exponentially with the increase in cell seeding density, even if the cells are exposed to incubator-like gas conditions. For the first time, we demonstrate that 3D, longitudinal oxygen imaging can be used to assess cells seeded in a hydrogel. These results demonstrate that MWIR-based EPROI is a versatile and robust method that can be utilized to observe the cell metabolic activity nondestructively, longitudinally, and in 3D. This approach may be useful for characterizing cell therapies, tissue-engineered medical products, and other advanced therapeutics.
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- Award ID(s):
- 2028829
- PAR ID:
- 10498318
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- npj Imaging
- Volume:
- 2
- Issue:
- 1
- ISSN:
- 2948-197X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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