Protective effects of anti-alginate monoclonal antibody against Pseudomonas aeruginosa infection of HeLa cells. (August 2020)

• Record Type: Journal Article
• Authors: Gao, Fei; Zhai, Guanxing; Wang, Hui; Lu, Lu; Xu, Jianrong; Zhu, Jianwei; Chen, Daijie; Lu, Huili
• Is Part Of: Microbial pathogenesis. Volume 145(2020)
• Publication Date: 2020-08
• Subjects: Pseudomonas aeruginosa -- Monoclonal antibody -- Alginate -- Biofilm -- Invasion -- HeLa cells; Pathogenic microorganisms -- Periodicals; Pathology, Molecular -- Periodicals; Communicable Diseases -- microbiology -- Periodicals; Communicable Diseases -- parasitology -- Periodicals; Micro-organismes pathogènes -- Périodiques; Pathologie moléculaire -- Périodiques; Electronic journals; 616.9041
• DOI: 10.1016/j.micpath.2020.104240
• Languages: English
• ISSNs: 0882-4010

Abstract

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. Highlights: An anti-alginate scFv-Fc monoclonal antibody MFb was developed and determined to be with high affinity to alginate. MFb can inhibit the biofilm formation, which is important for P. aeruginosa survival and infection. MFb significantly reduced the adhesion and invasion of P. aeruginosa on HeLa cells. MFb could enhance the phagocytotic capacity of macrophages for P. aeruginosa .