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

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.