Related Experiment Video
Updated: Jun 7, 2026
12:55
Scalable High Throughput Selection From Phage-displayed Synthetic Antibody Libraries
Published on: January 17, 2015
Identification of a high affinity TAG-72 binding peptide by phage display selection
Nan Xiao1, Dengfeng Cheng, Yi Wang
1University of Massachusetts Medical School, Worcester, Massachusetts, USA.
Cancer Biology & Therapy
|October 29, 2010
Summary
Researchers developed novel peptides using phage display to target TAG-72, a cancer antigen. One peptide, T3-15, shows sub-nanomolar affinity and promising results for in vivo cancer imaging.
Area of Science:
- Biotechnology
- Molecular Biology
- Oncology
Background:
- Tumor-associated glycoprotein 72 (TAG-72) is a target antigen expressed on various cancers.
- Developing specific and high-affinity binding agents is crucial for accurate cancer imaging.
Purpose of the Study:
- To select novel peptides via phage display that specifically bind TAG-72.
- To identify peptides with properties suitable for imaging TAG-72 positive cancers.
Main Methods:
- Phage display was employed using the f88-4/Cys6 library and distinct elution strategies.
- Selected phages were validated for TAG-72 binding using flow cytometry and immunofluorescence.
- Peptides were synthesized, radiolabeled with technetium-99m (99mTc), and evaluated in a mouse tumor model.
Main Results:
- Two consensus peptides, G3-15 and T3-15, were identified and displayed on phages.
- Both peptides demonstrated specific binding to TAG-72 in vitro and stability in serum.
- T3-15 exhibited a higher affinity (IC50 = 0.29 nM) compared to G3-15 (IC50 = 10.32 nM).
- In vivo studies showed preferential accumulation of 99mTc-T3-15 in tumors, confirmed by SPECT/CT imaging.
Conclusions:
- A novel peptide (T3-15) with sub-nanomolar affinity for TAG-72 was identified.
- This peptide demonstrates potential for targeted cancer imaging applications.
