NCIt definition : A family of proteins that bind and transport retinol and/or retinoids.;
NCIt note : There are 6 retinol binding proteins. 4 are cellular retinol-binding proteins (RBP1,
RBP2, RPB5 and RBP7), one is located in the plasma (RBP4) and one is considered interstitial
(RBP3).;