Preparation and Evaluation of Novel Epitope-Based ETEC K88-K99 Bivalent Vaccine
Simple Summary
Abstract
1. Introduction
2. Methods and Materials
2.1. Bacterial Strains and Plasmids
2.2. Bioinformatics-Based Prediction of K99-FanC Epitopes and FaeG-Ep Fusion Construction
2.3. Expression and Identification of the FaeG-Ep Fusion Protein and the FaeG and FanC Proteins
2.4. Enzyme-Linked Immunosorbent Assay (ELISA)
2.5. Mouse Immunization and Infection
- a. Mouse immunization
- b. Inhibition of bacterial adhesion with mouse serum IgG antibodies
- c. Mouse infection
2.6. Statistical Analyses
3. Result
3.1. Selection of K99 Immunodominant B-Cell Epitopes
3.2. Design of Peptide-Based Protein and Docking Analysis with Sus Scrofa Aminopeptidase N (APN) Receptors
3.3. Plasmid Construction and Expression of the FaeG-Ep Protein
3.4. Verification of the Effective Antigenic Epitope of FanC-Ep on the K88-FaeG-Ep Vaccine In Vitro
3.5. Verification of the Effective Antigenic Epitope of FanC-Ep in the K88-FaeG-Ep Vaccine In Vivo
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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Strains | Relevant Properties | Sources |
---|---|---|
C83549 | Porcine E. coli field isolate, K88ac | Hubei Academy of Agricultural Sciences |
C83644 | Porcine E. coli field isolate, K99 | |
pET/FaeG | FaeG + pET30α (+) in DH5α/BL21 | This study |
pET/FanC | FanC + pET30α (+) in DH5α/BL21 | This study |
pET/FaeG-Ep1 | FaeG-Ep1 + pET30α (+) in DH5α/BL21 | This study |
pET/FaeG-Ep2 | FaeG-Ep2 + pET30α (+) in DH5α/BL21 | This study |
pET/FaeG-Ep3 | FaeG-Ep3 + pET30α (+) in DH5α/BL21 | This study |
pET/FaeG-Ep4 | FaeG-Ep4 + pET30α (+) in DH5α/BL21 | This study |
pET/FaeG-Ep5 | FaeG-Ep5 + pET30α (+) in DH5α/BL21 | This study |
pET/FaeG-Ep6 | FaeG-Ep6 + pET30α (+) in DH5α/BL21 | This study |
Antigen Name | Concentration | p-Value | N-Value | p-Value/N-Value |
---|---|---|---|---|
K88-FaeG | 11.7 ng/mL | 1.18 | 0.12 | 9.86 |
K99-FanC | 93.75 ng/mL | 1.01 | 0.06 | 15.78 |
FaeG-Ep1 | 1 μg/mL | 1.0 | 0.07 | 14.23 |
FaeG-Ep2 | 46.87 ng/mL | 1.12 | 0.15 | 7.36 |
FaeG-Ep3 | 4 μg/mL | 0.95 | 0.09 | 10.23 |
FaeG-Ep4 | 4 μg/mL | 1.0 | 0.09 | 10.23 |
FaeG-Ep5 | 4 μg/mL | 0.93 | 0.06 | 13.63 |
FaeG-Ep6 | 187.5 ng/mL | 1.0 | 0.09 | 11.68 |
Antigen Name | Protein Sequence |
---|---|
K88 | FaeG |
K99 | FanC |
Epitope 1 | 30NGKITSATCT39 |
Epitope 2 | 40IEPEVNGNRT49 |
Epitope 3 | 88DWSGSMNS95 |
Epitope 4 | 101TASGNTAAK109 |
Epitope 5 | 122NGSGGANIN130 |
Epitope 6 | 155KDDRAPSNGG164 |
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Wang, S.; Yang, Y.; Yue, X.; Liu, Z.; Yuan, F.; Yang, K.; Zhu, J.; Liu, W.; Tian, Y.; Wu, Q.; et al. Preparation and Evaluation of Novel Epitope-Based ETEC K88-K99 Bivalent Vaccine. Vet. Sci. 2025, 12, 381. https://doi.org/10.3390/vetsci12040381
Wang S, Yang Y, Yue X, Liu Z, Yuan F, Yang K, Zhu J, Liu W, Tian Y, Wu Q, et al. Preparation and Evaluation of Novel Epitope-Based ETEC K88-K99 Bivalent Vaccine. Veterinary Sciences. 2025; 12(4):381. https://doi.org/10.3390/vetsci12040381
Chicago/Turabian StyleWang, Shuangshuang, Yuxin Yang, Xinru Yue, Zewen Liu, Fangyan Yuan, Keli Yang, Jiajia Zhu, Wei Liu, Yongxiang Tian, Qiong Wu, and et al. 2025. "Preparation and Evaluation of Novel Epitope-Based ETEC K88-K99 Bivalent Vaccine" Veterinary Sciences 12, no. 4: 381. https://doi.org/10.3390/vetsci12040381
APA StyleWang, S., Yang, Y., Yue, X., Liu, Z., Yuan, F., Yang, K., Zhu, J., Liu, W., Tian, Y., Wu, Q., Gao, T., Li, C., Song, H., Zhou, D., & Bei, W. (2025). Preparation and Evaluation of Novel Epitope-Based ETEC K88-K99 Bivalent Vaccine. Veterinary Sciences, 12(4), 381. https://doi.org/10.3390/vetsci12040381