Human RBP4 (amino acids 19-201) is fused at the N-terminus to a FLAG(R)-tag. Liquid. 0.2µm-filtered solution in PBS, pH 7.2. Retinol binding protein 4 (RBP4, RBP) is a 21kDa secreted protein, a member of the lipocalin family and is known as the primary transporter of retinol (vitamin A) to tissues. A recent report...