The protective effects of antigen-specific IgY on pyocyanin-treated human lymphoma Raji cells

Abstract

Background: Pyocyanin (PCN), a highly pathogenic pigment produced by Pseudomonas aeruginosa, induces caspase 3-dependent human B cell (Raji cells) death. The aim of the present study, therefore, was to assess whether antigen-specific IgY antibodies may be protective on PCN-induced Raji cell death. Methods: Chickens were subcutaneously immunized with Freund's complete adjuvant containing PCN, and then given two boosted immunizations. Anti-PCN IgY antibodies were purified from egg yolk and detected using an agar gel precipitation test (AGPT) and ELISA. Protective effects of antigen-specific IgY on Raji cells were tested using a cell viability assay. Results: AGPT results showed the formation of strong immune complex precipitates, whilst ELISA further confirmed the presence of IgY antibodies specific to PCN at significant concentration. Further experiments showed that anti-PCN IgY antibodies significantly increased PCN-treated Raji cell viability in a dose-dependent fashion (p<0.05). Conclusions: The results of the present study suggest that anti-PCN IgY antibodies may be protective on PCN-induced Raji cell death.

Potential Therapeutic Targets for Combination Antibody Therapy against Pseudomonas aeruginosa Infections

“…Pyocyanin is a small-molecule toxin that is easily able to cross cell membranes usually through a T2SS quorum-sensing dependent mechanism. Pyocyanin is a redox-active tricyclic zwitterion shown to affect the respiratory, cardiovascular, urological, and central nervous systems by inducing oxidative stress within cells [ 111 , 112 ]. Pyocyanin directly oxidizes and depletes reduced glutathione, effectively neutralizing one of the major redox pathways.…”

“…Due to this cascade, pyocyanin released by P. aeruginosa is especially toxic to cystic fibrosis patients, potentially due to its ability to induce neutrophil extracellular traps (NETs), which are able to exacerbate airway inflammation for their own benefit [ 113 ]. Thus, pyocyanin is a powerful mediator of cell injury used by P. aeruginosa and is a prime target to halt disease [ 112 ]. In fact, in vitro studies have demonstrated that anti-pyocyanin antibodies can provide protection [ 114 ].…”