Poster 119 - Non-Invasive Live Cell Thickness Monitoring of HEK239 via Eagle-Eye Inspired Meta Device

Saturday, October 26, 2024

10:00 AM - 12:00 PM EST

Location: Exhibit Hall E, F & G

Presenting Author(s)

Abigail Qiu

Student
Pacific Ridge School, United States

Co-Author(s)

Shivali Shrivastava (she/her/hers)

Student
Northwood High School, United States

Co-Author(s)

Bryce Liu

Student Mentor
University of California, San Diego: Institute of Engineering in Medicine, United States
Sarah Kocian-Rudenberg

Student Mentor
University of California, San Diego: Institute of Engineering in Medicine, California, United States
JZ

Junxiao Zhou

Postdoc
Electrical and Computer Engineering, United States
VG

Veronica Gomez-Godinez

Scientist
University of California, San Diego
La Jolla, California, United States

Primary Investigator(s)

Linda Shi, PhD (she/her/hers)

OPALS Program Director, Project Scientist, Co-director IEM
University of California, San Diego: Institute of Engineering in Medicine
La Jolla, California, United States

Last Author(s)

ZL

Zhaowei Liu

Professor
Electrical and Computer Engineering, United States

Introduction: Traditionally, cell imaging techniques involve staining or labeling cells with dyes which often interfere with cellular function and interactions. In contrast, non-invasive cell imaging allows for the observation of cells in their natural state, without compromising reliability and accuracy. An eagle's distinctive ocular structure features two convex lenses for both nearsightedness and farsightedness, therefore allowing the creature to perceive objects at varying distances with clarity. Inspired by the eagle's eyes, our non-invasive meta-device has nanostructures that focus incident light onto two focal planes, allowing us to extract QPI (Quantitative Phase Imaging) information from biological samples. Human Embryonic Kidney 293 Cells (HEK293) and their derived cell lines resemble native human tissue, making them ideal for developing biologics intended for human use. Additionally, biological samples exhibit favorable compatibility with the non-invasive properties of phase contrast methods used in QPI, ensuring that HEK293 remains untampered during imaging. When damaged, HEK293 exhibits thickness fluctuations which we closely monitor to understand cellular morphology under various conditions.

Materials and

Methods: This meta-device utilizes a polarized camera to simultaneously capture images for two different polarizations with slightly different focal distances. This setup enhances the clarity and detail of the images, providing more precise visualizations of cellular structures. HEK293 cells, chosen for their resemblance to native human tissue, were cultured in 60mm Nunc cell culture dishes using Advanced Dulbecco’s Modified Eagle Medium supplemented with 10% heat-inactivated fetal bovine serum and 1x Glutamax. The cells were incubated at 37°C with 5% CO2 to maintain optimal growth conditions. This non-invasive imaging approach preserves cell integrity, allowing for detailed observation of live cell thickness and morphology changes under various conditions, such as during laser ablation or other cell biology research.

Results, Conclusions, and Discussions: Results and Discussions: The changes in the HEK cell’s thickness as a function of time are observed. Shortly after the cell incurs laser ablation, cell thickness decreases locally at the site of the laser’s beam, as seen in Figure 1c and 1h. As time progresses, the tissue at the site of the laser’s beam shrinks further, and the tissue surrounding that at the site of the laser’s beam increases in thickness, as seen in Figure 1k and 1p. However, the cell as a whole eventually shrinks significantly, as evidenced by the decrease in cell size from Figure 1a and 1f to Figure 1o and 1t. The non-invasive technique of the experiment allows for increased contrast and visualizations of the fluctuations in cell thickness are more apparent.

Conclusions: Laser ablation sufficiently damages human embryonic kidney cells, as evidenced by the decrease in thickness at the site of the laser’s beam. The imaging process used in this research allows cell integrity to be preserved while providing researchers with a clear view of the cell at every step of its thickness changes. Furthermore, the non-invasive nature of the study allows for monitoring of the cell without any changes to the cell that could be caused by other methods. This research carries implications in the field of neurosurgery and brain tumor removal. For example, in a standard craniotomy procedure, the neurosurgeon must drill a large hole in the skull and manually destroy the brain tumor. This process is quite invasive and requires a long recovery time for the patient. If tumor cells behave similarly to human embryonic kidney cells in response to laser ablation, then laser ablation can be used instead of a standard craniotomy procedure. This process would be more precise and much less invasive, thus shortening the patient’s recovery time.

Acknowledgements (Optional): This work was supported by a generous gift from Beckman Laser Institute Inc. to L. S. & V. G. G. and National Science Foundation - MRI project # 2320437 to Z.W. The high school students (*) participated in the UCSD IEM OPALS internship. Special thanks to Dr. Shu Chien from UCSD Bioengineering and Dr. Lizhu Chen from CorDx Inc. for their donations

References (Optional):