Human Her2 / ErbB2 protein, His and GST tag

The epidermal growth factor receptor (EGFR; ErbB-1; HER1 in humans) is a transmembrane protein that is a receptor for members of the epidermal growth factor family (EGF family) of extracellular protein ligands. Epidermal growth factor receptor 2 (EGFR2) is a member of the epidermal growth factor (EGF) receptor family of receptor tyrosine kinases. The EGFR is essential for ductal development of the mammary glands, and agonists of the EGFR such as amphiregulin, TGF-α, and heregulin induce both ductal and lobuloalveolar development even in the absence of estrogen and progesterone. Besides, Actin Beta (ACTb) has been identified as an interactor of EGFR2, thus a binding ELISA assay was conducted to detect the interaction of recombinant human EGFR2 and recombinant human ACTb. Briefly, EGFR2 were diluted serially in PBS with 0.01% BSA (pH 7.4). Duplicate samples of 100 μl were then transferred to ACTb-coated microtiter wells and incubated for 2h at 37ºC. Wells were washed with PBST and incubated for 1h with anti-EGFR2 pAb, then aspirated and washed 3 times. After incubation with HRP labelled secondary antibody, wells were aspirated and washed 3 times. With the addition of substrate solution, wells were incubated 15-25 minutes at 37ºC. Finally, add 50 μl stop solution to the wells and read at 450nm immediately. The binding activity of EGFR2 and ACTb was in a dose dependent manner.