BALB/c mice were immunized intranasally with an adjuvant (cholera toxin B subunit containing 0.2% of the whole toxin)-combined with A or B virus recombinant NP. The NP-immune mice, when challenged intranasally with a sublethal dose of the virus 3 wk after immunization, had accelerated virus clearance from the nasal site in both an influenza type-specific and a nonspecific manner, as shown by the protection from high morbidity from the second day after challenge (Tamura et al., 1996).
Tamura et al., 1996: Tamura S, Miyata K, Matsuo K, Asanuma H, Takahashi H, Nakajima K, Suzuki Y, Aizawa C, Kurata T. Acceleration of influenza virus clearance by Th1 cells in the nasal site of mice immunized intranasally with adjuvant-combined recombinant nucleoprotein. Journal of immunology (Baltimore, Md. : 1950). 1996; 156(10); 3892-3900. [PubMed: 8621928].
