[Genetically encoded photoimmunosensitizer].

Area of Science:

• Biotechnology
• Molecular Biology
• Cancer Research

Context:

• Photoimmunotherapy utilizes photosensitizer-antibody conjugates for targeted cancer cell destruction.
• Chemical conjugation methods present challenges like low reproducibility and impurities.

Purpose:

• To develop a fully genetically encoded photoimmunosensitizer to overcome limitations of chemical conjugation.
• To create a fusion protein combining an anti-HER2/neu miniantibody with a phototoxic fluorescent protein.

Summary:

• A novel photoimmunosensitizer, 4D5scFv-KillerRed, was engineered by genetically fusing an anti-HER2/neu miniantibody (4D5scFv) with the phototoxic fluorescent protein KillerRed.
• This fusion protein maintains high affinity for the HER2/neu antigen and phototoxic activity.
• The 4D5scFv-KillerRed demonstrated high specificity for HER2/neu-over-expressing cells and effectively reduced their viability upon illumination.

Impact:

• Provides a more reproducible and potentially more effective method for targeted cancer therapy.
• Offers a new platform for developing genetically encoded targeted therapies.
• Demonstrates successful application of protein engineering for advanced photoimmunotherapy.