Figure 1
Development of a quantitative ELISA measuring RBP4 concentration in urine using a novel mAb. (a) The reactivity of the capture mAb AG102 was tested using Western blot with both recombinant and serum RBP4 proteins along with a control recombinant protein. (b) After making a serial deletion mutant RBP4 gene, these expression constructs were introduced in BL21, an IPTG-inducible E.coli host. Deletion points are indicated in Supplementary Table III, resulting in three deleted recombinant RBP4s. Upon IPTG induction, Western blot was conducted along with the use of a human serum or FLAG-RBP4. As a negative control, non-induced E.coli cell lysates were also used for the specificity of the Western blot. (c) The amino acids of human RBP4 are represented. Epitopes within the first 35 amino acid residues (bracketed) are recognized by AG102, which comprise four antigen binding sites and a joining region (J). The four critical amino acid residues involved in the TTR binding are depicted by red circles.
