Abstract: FR-PO991
Multiplexed Imaging of Senescent Chromatin States in Single Cells in Kidney
Session Information
- CKD Mechanisms: From Mendel to Mars
November 03, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Geriatric Nephrology
- 1300 Geriatric Nephrology
Authors
- Perry, Hannah S., University of Washington, Seattle, Washington, United States
- Wong, Madeline K., University of Washington, Seattle, Washington, United States
- Mustonen, Benjamin Christopher, University of Washington, Seattle, Washington, United States
- Vaughan, Joshua C., University of Washington, Seattle, Washington, United States
Background
The gradual loss of kidney function with age and disease can be linked to changes in physiology and single cell epigenetics. As cells become stressed or damaged from these conditions, they undergo the process of becoming senescent, a state of permanent cell cycle arrest associated with massive chromatin rearrangement, as a way to mitigate further damage. The order of events and extent of epigenetic changes within single cells and their correlation to physiological alterations as the kidney ages or becomes diseased and senescence forms are not fully understood.
Methods
Super-resolution optical microscopy techniques were used with advanced chemical labeling methods to concurrently study epigenetic states and nanoscale physiology in mouse kidney slices. We used multiplexed imaging to simultaneously study histone marks, gene loci, and tissue morphology at the single cell level.
Results
The use of optical super-resolution techniques allows for ~70 nm spatial resolution. Multiple histone modifications have been detected and quantified at locations of repetitive DNA sequences (telomeres, major and minor satellites) and genes of interest (e.g. Nphs2, CDKN1a/2a, PAI-1) in single cells with a high degree of accuracy. In the same sample, these single cell epigenetic signatures were correlated with nanoscale features within glomeruli. The quantification of these nanoscale features includes the glomerular basement membrane thickness, width of individual podocyte foot processes, and the size of endothelial fenestrations. Multiplexed imaging has allowed for the use of 6-8 unique stains in one sample, with the potential for more.
Conclusion
The combination of these advanced labeling methods and super-resolution optical microscopy techniques allow for an unprecedented view and correlation of single cell epigenetic states and nanoscale physiology in kidney tissue at many age points. Our approach has implications for identifying specific epigenetic changes in the kidney that precede the development of senescence and related diseases and their physiological markers. Understanding the sequence of events may assist in predicting disease formation along with studying the effectiveness of various treatments.
Funding
- NIDDK Support