[Adhesion of calcium oxalate crystal to Madin-Darby canine kidney cells: quantitative determination and effects of glycosaminoglycans (GAG) and cell injuries on adhesion]

The present investigation was designed to study adhesion of calcium oxalate crystals on the surface of intact MDCK cells quantitatively, and to estimate the effects of glycosaminoglycans (GAGs) and cell injuries on these adhesions. Calcium oxalate monohydrate (COM) crystals adhere to the cell surface by an active force, and the attachment is in a time and concentration dependency with plateau. Pre-treatments with low concentration of GAGs (chondroitin sulphate C, hyaluronic acid, heparan sulphate, heparin and sodium pentosan polysulphate) produce significant reductions of the adhesion. There are significant decreases of the adhesions with pre-treatments of Triton-X100, 0.1 N HCl and gentamicin. These phenomena might be induced by some alterations of cell surface structures or characters. The current quantitative system on MDCK cells should serve as a useful model for the investigations of interactions with crystals and tubular cells. Our studies may also support the hypothesis of attachment of microcrystals to the cellular membrane, which is one of the most important and the earliest process of the pathophysiology of kidney stone.