Kidney cells, also known as renal cells, are specialized cell types found in the kidneys, which are essential organs responsible for filtering waste products, excess water, and electrolytes from the blood to form urine. The kidneys also help regulate blood pressure, maintain the body’s acid-base balance, and produce various hormones that influence other physiological processes.

There are several types of kidney cells with distinct functions:

1. Nephron cells: The nephron is the functional unit of the kidney and consists of multiple cell types that contribute to the filtration and reabsorption processes. These include:a. Glomerular endothelial cells: These cells line the blood vessels in the glomerulus, which is responsible for the initial filtration of blood to form the primary filtrate.b. Podocytes: These specialized cells wrap around the glomerular capillaries and form filtration slits, which prevent large proteins and blood cells from passing into the primary filtrate.c. Proximal tubule cells: These cells are involved in the reabsorption of water, electrolytes, and essential nutrients from the primary filtrate back into the bloodstream.d. Loop of Henle cells: These cells participate in the regulation of the concentration of the urine by creating a concentration gradient in the renal medulla.e. Distal tubule cells: These cells regulate the final composition of urine by adjusting the reabsorption of water, electrolytes, and bicarbonate ions.f. Collecting duct cells: These cells fine-tune the urine concentration by controlling water reabsorption in response to the antidiuretic hormone (ADH) and regulating the final acid-base balance.
2. Interstitial cells: These cells are found in the renal interstitium and support the structure and function of the nephrons. They also contribute to hormone production and regulation of the extracellular matrix.
3. Vascular cells: The kidneys have an extensive vascular network, consisting of various cell types, such as endothelial cells, smooth muscle cells, and pericytes, which maintain blood flow and regulate blood pressure.
4. Renal tubular epithelial cells: These cells line the tubules and have various roles, including ion transport and waste removal.

Kidney cells are extensively used in research to study renal physiology, kidney diseases (such as chronic kidney disease and polycystic kidney disease), and the development of new therapeutics for renal conditions. Some widely used kidney cell lines include human embryonic kidney cells (HEK293) and immortalized renal proximal tubule epithelial cells (HK-2).