“…Mucosal immunization with influenza viral antigen can elicit robust immune response, but often the adjuvants used to enhance the immune response lead to safety issues, with side effects reported in clinical testing. 42,43 On the other hand, clinical trials have shown that formulations containing recombinant CTB are safe and well tolerated. 44,45 In our study, CTB fused to influenza antigens enhanced protective immunity in immunized mice.…”