Single domain antibodies specific for HER2 dimerization domain effectively disrupts HER2 dimerization

Area of Science:

• Oncology
• Molecular Biology
• Immunotechnology

Background:

• HER2 receptor dimerization drives signal transduction, correlating with cancer invasion and metastasis.
• New therapies target HER2 dimerization using antibodies, with phage display being a key manufacturing method.

Purpose of the Study:

• To develop and characterize a single-domain antibody (sdAb) targeting the HER2 receptor dimerization domain.
• To evaluate the therapeutic and diagnostic potential of the identified sdAb for HER2-positive cancers.

Main Methods:

• Phage display antibody library and subtractive biopanning to isolate HER2 dimerization domain-reactive clones.
• ELISA, MTT assay, Annexin V/PI staining, gene expression analysis, and in silico protein-protein docking to assess sdAb specificity, efficacy, and binding.
• PCR fingerprinting and polyclonal/monoclonal phage ELISA for biopanning success and clone selection.

Main Results:

• Isolation of several HER2 dimerization domain-reactive clones using subtractive biopanning and phage display.
• Selected monoclonal sdAbs demonstrated high affinity, specificity, and reactivity to the HER2 dimerization domain.
• Functional tests confirmed increased apoptosis rates and specific in silico binding to the HER2 dimerization domain.

Conclusions:

• A novel single-domain antibody targeting HER2 dimerization has been identified.
• This sdAb is a promising candidate for therapeutic and diagnostic applications in HER2-positive cancers.
• Further in vitro and in vivo studies are required to validate its clinical utility.