Protective effects of anti-alginate monoclonal antibody against Pseudomonas aeruginosa infection of HeLa cells

Fei Gao; Guanxing Zhai; Hui Wang; Lu Lu; Jianrong Xu; Jianwei Zhu; Daijie Chen; Huili Lu

doi:10.1016/j.micpath.2020.104240

Protective effects of anti-alginate monoclonal antibody against Pseudomonas aeruginosa infection of HeLa cells

Microb Pathog. 2020 Aug:145:104240. doi: 10.1016/j.micpath.2020.104240. Epub 2020 Apr 30.

Authors

Fei Gao¹, Guanxing Zhai², Hui Wang¹, Lu Lu³, Jianrong Xu⁴, Jianwei Zhu¹, Daijie Chen⁵, Huili Lu⁶

Affiliations

¹ Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China.
² Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China; College of Life Sciences, Shanghai Normal University, Shanghai, 200233, China.
³ School of Biotechnology, East China University of Science and Technology, Shanghai, China.
⁴ Department of Pharmacology and Chemical Biology, Institute of Medical Sciences, Shanghai Jiao Tong University School of Medicine, 280 South Chongqing Road, Shanghai, 200025, China.
⁵ Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China; College of Life Sciences, Shanghai Normal University, Shanghai, 200233, China; School of Biotechnology, East China University of Science and Technology, Shanghai, China. Electronic address: cdj@sjtu.edu.cn.
⁶ Engineering Research Center of Cell & Therapeutic Antibody, Ministry of Education, School of Pharmacy, Shanghai Jiao Tong University, Shanghai, 200240, China. Electronic address: roadeer@sjtu.edu.cn.

PMID: 32360522
DOI: 10.1016/j.micpath.2020.104240

Abstract

Pseudomonas aeruginosa is an opportunistic pathogen that is highly resistant to antibiotics, especially when it grows in biofilms. As an alternative to antibiotic intervention, antimicrobial antibody drugs have drawn attention in recent years due to their immunotherapeutic functions. In this study, we designed a monoclonal scFv-Fc-form antibody, MFb, targeting P. aeruginosa antigen alginate and investigated its function against this bacterium in vitro. MFb was generated by transient gene expression in HEK293 cells and purified by one-step protein A affinity chromatography. Experiments showed that MFb could recognize alginate specifically based on enzyme-linked immunosorbent assays. Its KD value of 8.31 nM was determined by surface plasmon resonance, demonstrating its high affinity for alginate. Further detailed studies revealed that the antibody exerted antibacterial effects by three mechanisms: 1) MFb inhibited P. aeruginosa biofilm formation with an IC₅₀ of 0.58 μg/mL; 2) MFb reduced P. aeruginosa adhesion to HeLa cells, and successfully prevented its invasion on epithelial cells; 3) based on an in vitro macrophage phagocytosis assay, MFb could enhance the phagocytotic capacity of macrophages for P. aeruginosa in a concentration-dependent manner. Taken together, our work demonstrated that the antimicrobial monoclonal antibody MFb has a protective effect on HeLa cells, and it may be a promising novel strategy to treat P. aeruginosa infection.

Keywords: Alginate; Biofilm; HeLa cells; Invasion; Monoclonal antibody; Pseudomonas aeruginosa.

MeSH terms

Alginates
Anti-Bacterial Agents / pharmacology
Antibodies, Monoclonal
Biofilms
HEK293 Cells
HeLa Cells
Humans
Pseudomonas Infections* / drug therapy
Pseudomonas aeruginosa

Substances

Alginates
Anti-Bacterial Agents
Antibodies, Monoclonal