A New Protein–Ligand Trapping System to Rapidly Screen and Discover Small-Molecule Inhibitors of PD-L1 from Natural Products
Abstract
:1. Introduction
2. Results and Discussion
2.1. The Effectiveness of the New PLT System Validated by Positive Medicine
2.2. PD-L1 Binding Active Compounds in TA Screened by New PLT System
2.3. SPR Validation Results: PD-L1 Binding Affinity at the Molecular Level
2.4. Cytopharmacology Validation Results: PD-1/PD-L1 Inhibiting Activity at the Cellular Level
2.4.1. Cytotoxicity and Concentration Design of the In Vitro Study
2.4.2. Immunofluorescence Validation Results: PD-1/PD-L1 Inhibiting Activity
2.4.3. Inhibitors May Promote A549 Apoptosis When Cocultured with PBMCs Induced by PD-1/PD-L1
3. Experimental Section
3.1. Materials
3.1.1. Reagents and Chemicals
3.1.2. Escherichia coli and Cell Culture
3.1.3. TA Sample Solution Preparation and Positive Medicine Selection
3.1.4. PD-L1 DNA Plasmid (Extracellular Fragment) Preparation and hPD-L1 Recombinant Protein Expression in Mammalian Cells
3.1.5. PD-L1 Protein Immobilized Affinity Column (PD-L1 Protein Column) Synthesis
3.2. Methods
4. Discussion
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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NO. | Peak | TR (min) | An | Ap | RCP (%) | Peak Area Drop Value |
---|---|---|---|---|---|---|
2 | 7 | 10.278 | 217,068 | 95,476 | −56.015626 | 121,592 |
3 | 8 | 15.546 | 497,316 | 405,786 | −18.404797 | 91,530 |
6 | 11 | 26.808 | 1,489,829 | 1,042,284 | −30.040025 | 447,545 |
7 | 12 | 32.328 | 395,747 | 58,265 | −85.27721 | 337,482 |
12 | 15 | 58.773 | 5,312,326 | 5,110,540 | −3.7984491 | 201,786 |
13 | 16 | 60.376 | 818,092 | 656,451 | −19.758291 | 161,641 |
14 | 17 | 61.762 | 108,244 | 29,147 | −73.072872 | 79,097 |
19 | 20 | 70.308 | 3,480,298 | 3,342,819 | −3.9502077 | 137,479 |
22 | 22 | 73.297 | 425,276 | 62,145 | −85.387137 | 363,131 |
34 | 27 | 87.459 | 2,469,279 | 2,220,585 | −10.071523 | 248,694 |
45 | 29 | 96.103 | 6,282,474 | 6,069,301 | −3.3931378 | 213,173 |
63/64 | 39 | 114.078 | 2,164,023 | 2,073,044 | −4.2041605 | 90,979 |
68 | 41 | 116.525 | 5,727,162 | 5,472,947 | −4.4387604 | 254,215 |
24 | 23 | 76.127 | - | - | - | - |
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Huang, Y.; Sun, S.; Yin, R.; Lin, Z.; Wang, D.; Wang, W.; Fu, X.; Wang, J.; Lei, X.; Sun, M.; et al. A New Protein–Ligand Trapping System to Rapidly Screen and Discover Small-Molecule Inhibitors of PD-L1 from Natural Products. Molecules 2025, 30, 1754. https://doi.org/10.3390/molecules30081754
Huang Y, Sun S, Yin R, Lin Z, Wang D, Wang W, Fu X, Wang J, Lei X, Sun M, et al. A New Protein–Ligand Trapping System to Rapidly Screen and Discover Small-Molecule Inhibitors of PD-L1 from Natural Products. Molecules. 2025; 30(8):1754. https://doi.org/10.3390/molecules30081754
Chicago/Turabian StyleHuang, Yazhuo, Senfeng Sun, Runxin Yin, Zongtao Lin, Daidong Wang, Wanwan Wang, Xiangyu Fu, Jing Wang, Xinyu Lei, Mimi Sun, and et al. 2025. "A New Protein–Ligand Trapping System to Rapidly Screen and Discover Small-Molecule Inhibitors of PD-L1 from Natural Products" Molecules 30, no. 8: 1754. https://doi.org/10.3390/molecules30081754
APA StyleHuang, Y., Sun, S., Yin, R., Lin, Z., Wang, D., Wang, W., Fu, X., Wang, J., Lei, X., Sun, M., Chen, S., & Wang, H. (2025). A New Protein–Ligand Trapping System to Rapidly Screen and Discover Small-Molecule Inhibitors of PD-L1 from Natural Products. Molecules, 30(8), 1754. https://doi.org/10.3390/molecules30081754