Chronic kidney disease (CKD) is a common progressive disease condition in elderly cats with no known cause and no definitive cure other than kidney transplantation. Administration of mesenchymal stem cells (MSC) has been shown to improve kidney function in rodent models of CKD, in part by reducing inflammation and scarring in the kidney. CKD in cats is characterized by inflammation and scarring within the kidney, and thus treatment with MSC might improve kidney function. Previous studies in cats have demonstrated that systemic intravenous administration of cultured MSC administered to cats with CKD is safe and results in variable improvement in kidney function. However results have not been as striking as those seen in rodent models. When MSCs are administered intravenously the entire dose likely does not reach the kidney and therefore alternative methods of more effective administration should be assessed. The aim of the proposed study is to assess the safety and efficacy of MSC harvested from the fat of donor cats and administered directly into the kidney artery using minimally-‐invasive image guided radiologic techniques. The procedure will bypass the initial uptake of stem cells by the lungs and other organs and deliver a larger number of cells directly to the diseased kidney.