Renal cell markers: lighthouses for managing renal diseases

Abstract

Kidneys, one of the vital organs in our body, are responsible for maintaining whole-body homeostasis. The complexity of renal function (e.g., filtration, reabsorption, fluid and electrolyte regulation, urine production) demands diversity not only at the level of cell types but also in their overall distribution and structural framework within the kidney. To gain an in-depth molecular-level understanding of the renal system, it is imperative to discern the components of kidney and the types of cells residing in each of the sub-regions. Recent developments in labeling, tracing, and imaging techniques enabled us to mark, monitor and identify these cells in vivo with high efficiency in a minimally invasive manner. In this review, we have summarized different cell types, specific markers that are uniquely associated with those cell types, and their distribution in kidney, which altogether make kidneys so special and different. Cellular sorting based on the presence of certain proteins on the cell surface allowed for assignment of multiple markers for each cell type. However, different studies using different techniques have found contradictions in the cell-type specific markers. Thus, the term "cell marker" might be imprecise and sub-optimal, leading to uncertainty when interpreting the data. Therefore, we strongly believe that there is an unmet need to define the best cell markers for a cell type. Although, the compendium of renal-selective marker proteins presented in this review is a resource that may be useful to the researchers, we acknowledge that the list may not be necessarily exhaustive.

A novel mouse model for an inducible gene modification in the renal thick ascending limb

“…S1). In contrast to NKCC2, expression of other relevant TAL gene products, such as the ROMK channel, the Na + /H + exchanger 3, the Cl − channel ClC-Kb, the Ca 2+ -sensing receptor, and the secreted protein uromodulin ( 36 ) did not differ significantly between kidneys from male wild-type and Slc12a1-CreERT2 wt/tg mice ( Fig. 6 and Supplemental Table S2), suggesting a specific effect of transgene expression on the NKCC2 locus.…”

Review on the neuron damage parameters in patients with end-stage renal disease

“…In immature glomeruli, Nestin is expressed in the progenitors of glomerular endothelial cells. Nestin is also transiently expressed by epithelial cells of immature proximal tubules in the newborn kidney [77,78]. Upon differentiation, nestin becomes downregulated and is replaced by tissue-specific intermediate filament proteins.…”

Research progress of natural active compounds on improving podocyte function to reduce proteinuria in diabetic kidney disease

“…Synaptopodin, a proline-rich actin-binding protein, is involved in the regulation of actin cytoskeleton polymerization and dissociation, and is localized in the foot processes of mature podocytes [ 39 ]. Synaptopodin binds to α-actinin-4, regulates podocyte contraction and extension, participates in cytoskeletal movement, and plays an important role in maintaining actin cytoskeleton integrity and cell migration [ 40 ]. Studies have shown that urinary synaptopodin levels are significantly increased in patients with DKD, which is closely related to disease stage and eGFR.…”

“…On the one hand, podocalyxin prevents adhesion of foot processes between adjacent podocytes to maintain the stability of foot processes. In contrast, the negative charge of podocalyxin can ensure the integrity of the glomerular charge barrier and prevent negatively charged protein molecules from entering the ultrafiltrate through the charge barrier of the glomerular filtration membrane to form proteinuria [ 40 ].…”