Although the results of relations between circulating klotho levels and outcomes of CKD are contradictory, three commonly used commercial immunoassay products for measuring soluble klotho-- are available from IBL (IBL International GmbH, Hamburg, Germany), Cusabio (Cusabio Biotech, Wuhan, China), and USCN (USCN Life Science Inc., Wuhan, China) [159]. Here, KL is linked to chronic kidney disease.