Competitional binding between the natural ligand HRG and Affibody molecules to the HER3-positive breast cancer cell line AU565 visualised by confocal microscopy.

<p>AU565 cells were pretreated with Affibody molecules (Z05416, Z05417 or ZTaq) or PBS only (HRG) before addition of HRG in conjugation with a fluorophore. HRG binding to cells is shown in green while nuclear staining by DAPI is shown in blue.