Evaluation of cell-mediated immunity of E.coli nanovaccines in chickens

Nanovaccine is a revolutionary type of immunizations for various diseases that is simple to manufacture and administer. As a result, we are working to develop innovative nanovaccines against E. coli, which is capable of causing disease both inside and outside of its predilection sites, causing respiratory and systemic disease (colibacillosis).Colibacillosis is a global disease that significantly affects poultry production. The present study aims to evaluate in vivo cell-mediated immunity against a chitosan-nanovaccine from E. coli serogroups O1 and O78 to aid in limiting colibacillosis in chicken. Two hundred specific pathogen-free (SPF) three weeks old broiler chickens were used and divided into five groups: the first group inoculated with the outer membrane and flagellar antigen (OF), the second group inoculated with chitosan capsulated-outer membrane protein-flagellar antigen (CS_C-O-F), the third group inoculated with chitosan loaded-outer membrane protein-flagellar antigen (CS_L-O-F), the fourth group was vaccinated with (CS_L-O-F-M) adjuvanted with Montanide ISA 71 RVG, and the fifth group was left as unvaccinated control. The immune response was measured by ELISA, lymphocyte proliferation test, and challenge test. The duration of immunity was also studied. The CS_L-O-F-M had the highest antibody titer in an ELISA test using the O1 strain, and the CS_C-O-F had the highest antibody titer in an ELISA test using the O78 strain. For both O1 and O78 strains, the CS_L-O-F-M had the strongest cell-mediated immune response, which was validated by the challenge test and duration study. We recommend producing nanovaccines (CS_L-O-F-M) from E.coli O1 and O78 strains as a new manufacturing vaccine based on the demonstrated results. Because it produces highly effective humoral and cell-mediated immune responses, this novel vaccine may be useful in reducing the risk of colibacillosis.