Abstract
Molecular assessments at the single cell level can accelerate biological research by providing detailed assessments of cellular organization and tissue heterogeneity in both disease and health. The human kidney has complex multi-cellular states with varying functionality, much of which can now be completely harnessed with recent technological advances in tissue proteomics at a near single-cell level. We discuss the foundational steps in the first application of this mass spectrometry (MS) based proteomics method for analysis of sub-sections of the normal human kidney, as part of the Kidney Precision Medicine Project (KPMP). Using ~30–40 laser captured micro-dissected kidney cells, we identified more than 2,500 human proteins, with specificity to the proximal tubular (PT; n = 25 proteins) and glomerular (Glom; n = 67 proteins) regions of the kidney and their unique metabolic functions. This pilot study provides the roadmap for application of our near-single-cell proteomics workflow for analysis of other renal micro-compartments, on a larger scale, to unravel perturbations of renal sub-cellular function in the normal kidney as well as different etiologies of acute and chronic kidney disease.
Highlights
Recent advances in molecular profiling, transcriptional analysis at a single cell level, can uncover rare cell populations within heterogeneous clinical tissues, which is contributing to our understanding of kidney biology, and its molecular processes [1,2,3,4,5,6,7]
To evaluate what protein enrichment is seen between different collection methods, we found that optimal cutting temperature compound (OCT) tissue proteomics yielded more proteins with high spectral counts ≥ 5, which may reflect better preservation of kidney tissue in OCT (Figure 2C)
Across the 9 normal human kidneys processed by nscProteomics, with input of an average of 10–40 cells input each/Glom and proximal tubular (PT) fraction, we identified an average of ∼2,560 proteins/sample
Summary
Recent advances in molecular profiling, transcriptional analysis at a single cell level, can uncover rare cell populations within heterogeneous clinical tissues, which is contributing to our understanding of kidney biology, and its molecular processes [1,2,3,4,5,6,7]. Our group has recently reported on a near-single-cell proteomics (nscProteomics) method in HeLa cells, which provides a highly innovative and sensitive technology for proteome measurements of samples with subnanogram amounts of protein from a small number of cells [10]. This method requires highly customized sample processing equipment, and is difficult to transfer out to other research labs in its current state of development.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
