RBP5 is a member of the Retinol-binding proteins family. Estimation of retinol-binding protein is used to determine visceral protein mass in nutritional studies related to health. RBP5 has a higher expression in the adult kidney and liver and to a lesser extent in the adult and fetal spleen,adult lymph nodes and appendix,and fetal liver and kidney. RBP5 expression is strongly decreased in hepatocellular carcinoma tissues.