Evaluation of Immunoprotective Efficacy of Recombinant Pseudomonas plecoglossicida TolC Protein(rPpTolC)in Zebrafish

The PptolC gene was successfully cloned, and its B-cell antigenic epitopes and sequence conservation were analyzed. Zebrafish were immunized with rPpTolC to assess its capacity to induce non-specific immune responses and immunoglobulin production, as well as its protective efficacy against challenges with heterologous pathogens.

Results showed that PpTolC encodes a 457-amino acid protein with high sequence conservation and five high-confidence B-cell antigenic epitopes. Zebrafish were immunized with rPpTolC to assess its capacity to induce non-specific immune responses(such as myd88, tnf-α and tgf-β1)and immunoglobulin production(IgM, IgD, IgZ)in gill and intestinal tissues. Following separate challenges with P. plecoglossicida and Vibrio parahaemolyticus(each at 2×LD50), immunized zebrafish exhibited survival rates exceeding 60% against both pathogens individually.