Elsevier

Kidney International

Volume 54, Issue 3, September 1998, Pages 796-803
Kidney International

Cell Biology – Immunology – Pathology
Direct nucleation of calcium oxalate dihydrate crystals onto the surface of living renal epithelial cells in culture

https://doi.org/10.1046/j.1523-1755.1998.00058.xGet rights and content
Under an Elsevier user license
open archive

Direct nucleation of calcium oxalate dihydrate crystals onto the surface of living renal epithelial cells in culture.

Background

The interaction of the most common crystal in human urine, calcium oxalate dihydrate (COD), with the surface of monkey renal epithelial cells (BSC-1 line) was studied to identify initiating events in kidney stone formation.

Methods

To determine if COD crystals could nucleate directly onto the apical cell surface, a novel technique utilizing vapor diffusion of oxalic acid was employed. Cells were grown to confluence in the inner four wells of 24-well plates. At the start of each experiment, diethyloxalate in water was placed into eight adjacent wells, and the plates were sealed tightly with tape so that oxalic acid vapor diffused into a calcium-containing buffer overlying the cells.

Results

Small crystals were visualized on the cell surface after two hours, and by six hours the unambiguous habitus of COD was confirmed. Nucleation onto cells occurred almost exclusively via the (001) face, one that is only rarely observed when COD crystals nucleate onto inanimate surfaces. Similar results were obtained when canine renal epithelial cells (MDCK line) were used as a substrate for nucleation. Initially, COD crystals were internalized almost as quickly as they formed on the apical cell surface.

Conclusions

Face-specific COD crystal nucleation onto the apical surface of living renal epithelial cells followed by internalization is a heretofore unrecognized physiological event, suggesting a new mechanism to explain crystal retention within the nephron, and perhaps kidney stone formation when this process is dysregulated or overwhelmed.

Keywords

calcium oxalate
cell membrane
crystallization
crystallography
x-ray of kidney calculi
models of stones
structural defects

Cited by (0)