KL and endothelial dysfunction: More recently, Castellano and colleagues analyzed the role of anti-senescence protein Klotho in the kidney transplant setting: Klotho levels were significantly reduced in DGF patients, suggesting that Klotho deficiency may play a significant role in DGF-associated chronic allograft dysfunction due to its pleiotropic functions (prevention of fibrosis and endothelial dysfunction) [15].