MRI-based glomerular morphology and pathology in whole human kidneys

Area of Science:

• Nephrology
• Biomedical Imaging
• Medical Diagnostics

Background:

• Glomeruli number and size are linked to chronic kidney and cardiovascular disease risk.
• Assessing these parameters in intact kidneys is currently not possible.
• Glomeruli characteristics may predict renal allograft viability.

Purpose of the Study:

• To demonstrate cationized ferritin (CF) as an MRI contrast agent for measuring glomeruli number and size in intact human kidneys.
• To establish a non-invasive method for assessing kidney structure and disease.
• To explore the predictive value of glomeruli distribution for kidney disease.

Main Methods:

• Intravenous injection of cationized ferritin (CF) into viable human kidneys.
• Three-dimensional MRI imaging of CF-labeled kidneys.
• Custom software for identifying, counting, and measuring CF-labeled glomeruli.
• Immunofluorescence and electron microscopy for CF binding confirmation.
• Image texture analyses for quantifying CF distribution variations.

Main Results:

• CF successfully labeled glomeruli in intact human kidneys, appearing as punctate spots on MRI.
• The MRI-based technique accurately measured glomeruli number and volume, comparable to stereological estimates.
• A novel whole-kidney distribution of glomerular volumes was obtained.
• CF distribution patterns showed potential as a marker for glomerular sclerosis and vascular disease.

Conclusions:

• This study presents the first direct measurement of glomerular number and volume in intact human kidneys using MRI and CF.
• The developed technique provides a non-invasive tool for assessing kidney health and disease.
• CF distribution analysis may serve as a valuable biomarker for glomerular and vascular pathologies.