The Phospho-ErbB2 (Tyr1221/Tyr1222) antibody is a key tool for studying the activation status of ErbB2 (HER2/neu), a receptor tyrosine kinase belonging to the EGFR family. ErbB2 lacks a direct ligand-binding domain but acts as a preferred dimerization partner for other ErbB receptors. Phosphorylation at tyrosine residues 1221 and 1222. located in the activation loop of its kinase domain, is critical for receptor activation, downstream signaling, and oncogenic activity. These sites are autophosphorylated upon receptor dimerization, triggering signaling cascades like PI3K/Akt and MAPK pathways, which drive cell proliferation, survival, and metastasis.
This antibody specifically detects ErbB2 phosphorylated at these residues, enabling researchers to assess HER2 activation in cancer models or clinical samples. Overexpression or hyperactivation of HER2 is linked to aggressive breast, gastric, and ovarian cancers. Clinically, HER2 status guides targeted therapies such as trastuzumab. The antibody is widely used in techniques like Western blotting, immunohistochemistry, and immunofluorescence to evaluate HER2-targeted drug efficacy, study resistance mechanisms, or correlate phosphorylation with disease progression. Its specificity helps distinguish activated HER2 from total HER2 levels, providing insights into signaling dynamics in tumor biology and therapeutic response.