rN protein  N/A  Freund’s  I.P.  BALB/c mice  Elicits SARS-CoV N-specific Abs (IgG (1:1.8 × 103), IgG1, and IgG2a) in mice  Induces cellular immune responses with up-regulated IFN-γ and IL-10 cytokines in mice  N/A  Zheng et al., 2009