Citation: | WANG Xuefang, ZHAO Yang, LIU Zhuqing, et al. Genetic engineering and molecular modification of recombinant fully humanized single-domain antibody against Helicobacter pylori UreB[J]. J China Pharm Univ, 2024, 55(5): 666 − 672. DOI: 10.11665/j.issn.1000-5048.2023122903 |
To construct a recombinant expression system for a single-domain antibody targeting the urease of Helicobacter pylori (Hp), this study employed several strategies. First, using artificial intelligence (AI) auxiliary tools such as Pymol, I-TASSER, and ClussPro2, the molecular interactions between different antibodies and Hp urease subunit B (UreB) were analyzed. The fully humanized single-domain antibody UreBAb was identified as the primary research target. Next, the UreBAb gene sequence was optimized based on Escherichia coli codon preferences, and was inserted into expression vectors such as pET28a and pE-SUMO. The resulting recombinant expression strains were obtained by transforming Escherichia coli Rosetta(DE3). Recombinant antibody proteins were prepared through IPTG induction, and its activity was detected using extracted Hp urease as the antigen. SDS-PAGE analysis confirmed the correct expression of both UreBAb and SUMO-UreBAb, with protein yields of 0.34 mg/mL and 0.41 mg/mL, respectively. Unidirectional immunodiffusion experiments further confirmed that both recombinant antibodies exhibited strong affinity for Hp UreB antigen, with inhibition rates of 51.27% and 74.07%, respectively. Additionally, leveraging artificial intelligence tools such as AlphaFold2, cluspro2, mCSM-AB, OSPREY, and FoldX, the study evaluated and analyzed key binding sites and mutational strategies affecting the stability of the antigen-antibody complex. Subsequently, nine UreBAb evolution mutants were constructed, and their binding activities with the antigen were enhanced. Among these, the I107W mutant showed the most significant improvement, achieving a 24.95% increase compared to the wild-type UreBAb. This research lays a solid foundation for the development of fully humanized single-domain antibodies against Hp.
[1] |
Luo JS, He M, Yang GQ. Clinical diagnosis, formation mechanism and clinical treatment of gastric cancer[J]. Genomics Appl Biol(基因组学与应用生物学), 2021, 40(2): 936-940.
|
[2] |
Banks M, Graham D, Jansen M, et al. British Society of Gastroenterology guidelines on the diagnosis and management of patients at risk of gastric adenocarcinoma[J]. Gut, 2019, 68(9): 1545-1575. doi: 10.1136/gutjnl-2018-318126
|
[3] |
Malfertheiner P, Camargo MC, El-Omar E, et al. Helicobacter pylori infection[J]. Nat Rev Dis Primers, 2023, 9(1): 19.
|
[4] |
Tshibangu-Kabamba E, Yamaoka Y. Helicobacter pylori infection and antibiotic resistance—from biology to clinical implications[J]. Nat Rev Gastroenterol Hepatol, 2021, 18: 613-629. doi: 10.1038/s41575-021-00449-x
|
[5] |
Boquet P, Ricci V. Intoxication strategy of Helicobacter pylori VacA toxin[J]. Trends Microbiol, 2012, 20(4): 165-174. doi: 10.1016/j.tim.2012.01.008
|
[6] |
Qin Q, Liu H, He WB, et al. Single Domain Antibody application in bacterial infection diagnosis and neutralization[J]. Front Immunol, 2022, 13: 1014377. doi: 10.3389/fimmu.2022.1014377
|
[7] |
Rossotti MA, Bélanger K, Henry KA, et al. Immunogenicity and humanization of single-domain antibodies[J]. FEBS J, 2022, 289(14): 4304-4327. doi: 10.1111/febs.15809
|
[8] |
Wang Y, Zhao YJ, Li S. Application of nano-antibodies in the study of g protein-coupled receptors[J]. Acta Pharm Sin(药学学报), 2022, 57(4): 990-1001.
|
[9] |
Barderas R, Desmet J, Timmerman P, et al. Affinity maturation of antibodies assisted by in silico modeling[J]. Proc Natl Acad Sci U S A, 2008, 105(26): 9029-9034. doi: 10.1073/pnas.0801221105
|
[10] |
Fouladi M, Sarhadi S, Tohidkia M, et al. Selection of a fully human single domain antibody specific to Helicobacter pylori urease[J]. Appl Microbiol Biotechnol, 2019, 103(8): 3407-3420. doi: 10.1007/s00253-019-09674-6
|
[11] |
Fahimi F, Sarhaddi S, Fouladi M, et al. Phage display-derived antibody fragments against conserved regions of VacA toxin of Helicobacter pylori[J]. Appl Microbiol Biotechnol, 2018, 102(16): 6899-6913. doi: 10.1007/s00253-018-9068-4
|
[12] |
Mirdita M, Schütze K, Moriwaki Y, et al. ColabFold: making protein folding accessible to all[J]. Nat Methods, 2022, 19(6): 679-682. doi: 10.1038/s41592-022-01488-1
|
[13] |
Cheng X, Wang JW, Kang GB, et al. Homology modeling-based in silico affinity maturation improves the affinity of a nanobody[J]. Int J Mol Sci, 2019, 20(17): 4187. doi: 10.3390/ijms20174187
|
[14] |
Elbehiry A, Marzouk E, Aldubaib M, et al. Helicobacter pylori infection: current status and future prospects on diagnostic, therapeutic and control challenges[J]. Antibiotics, 2023, 12(2): 191.
|
[15] |
De Brito BB, Da Silva FAF, Soares AS, et al. Helicobacter pylori pathogenesis and clinical management of gastric infection[J]. World J Gastroenterol, 2019, 25 (37): 5578-5589.
|
[16] |
Yu HZ, H J, Li BC, et al. Effect of carboxymethyl chitosan bismuth salt on gastric ulcer of Helicobacter pylori in rats[J]. J China Pham Univ(中国药科大学学报), 2008, 39(2): 174-177.
|