Application of peptide barcoding to obtain high-affinity anti-PD-1 nanobodies
Takumi Miyazaki1, Wataru Aoki2, Naoki Koike3
1Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.
Abstract:
Cancer treatment has been revolutionized by immune checkpoint inhibitors, which regulate immune cell function by blocking the interactions between immune checkpoint molecules and their ligands. The interaction between programmed cell death-1 (PD-1) and programmed cell death-ligand 1 (PD-L1) is a target for immune checkpoint inhibitors. Nanobodies, which are recombinant variable domains of heavy-chain-only antibodies, can replace existing immune checkpoint inhibitors, such as anti-PD-1 or anti-PD-L1 conventional antibodies. However, the screening process for high-affinity nanobodies is laborious and time-consuming. Here, we identified high-affinity anti-PD-1 nanobodies using peptide barcoding, which enabled reliable and efficient screening by distinguishing each nanobody with a peptide barcode that was genetically appended to each nanobody. We prepared a peptide-barcoded nanobody (PBNb) library with thousands of variants. Three high-affinity PBNbs were identified from the PBNb library by quantifying the peptide barcodes derived from high-affinity PBNbs. Furthermore, these three PBNbs neutralized the interaction between PD-1 and PD-L1. Our results demonstrate the utility of peptide barcoding and the resulting nanobodies can be used as experimental tools and antitumor agents.
Insights
Researchers developed a novel peptide barcoding method to efficiently screen for high-affinity nanobodies targeting programmed cell death-1 (PD-1). These nanobodies show promise as experimental tools and potential antitumor agents in cancer therapy.
Area of Science:
- Immunology
- Biotechnology
- Nanotechnology
Background:
- Immune checkpoint inhibitors revolutionize cancer treatment by modulating immune cell function.
- Targeting the programmed cell death-1 (PD-1) and programmed cell death-ligand 1 (PD-L1) interaction is a key strategy.
- Nanobodies offer an alternative to conventional antibodies for immune checkpoint inhibition.
Purpose of the Study:
- To develop an efficient method for screening high-affinity nanobodies against PD-1.
- To identify novel nanobodies that can neutralize the PD-1/PD-L1 interaction.
- To demonstrate the utility of peptide barcoding for nanobody discovery.
Main Methods:
- Construction of a peptide-barcoded nanobody (PBNb) library.
- High-throughput screening using peptide barcoding to identify nanobodies.
- Quantification of peptide barcodes to determine nanobody affinity.
- Validation of nanobody neutralization of PD-1/PD-L1 interaction.
Main Results:
- Identification of three high-affinity anti-PD-1 nanobodies from the PBNb library.
- Demonstration of efficient and reliable nanobody screening via peptide barcoding.
- Confirmation that the identified nanobodies neutralize the PD-1/PD-L1 interaction.
Conclusions:
- Peptide barcoding is a powerful tool for efficient nanobody screening.
- The identified anti-PD-1 nanobodies are potential candidates for cancer immunotherapy.
- These nanobodies can serve as valuable experimental tools and therapeutic agents.
