Table 3.

Overview of published preclinical studies that combined nucleocapsid with other antigens of SARS-CoV-2.

	Platform	Animal model	Antigen	Dose and route	Immune response	Protection	Cross-reaction with VOC	Ref
1	DNA/viral vector pcDNA and SeV	Cynomolgus macaques	Nucleocapsid + membrane + envolve pcDNA/NME	Two, pcDNA/NME boost with SeV-NME. IM	IFN-γ	Positive	UD	[108]
2	DNA	BALB/c and h ACE-II mice	RBD VOCS, nucleocapsid and membrane	Three, 50 µg, IM	IgG Ab IFN-γ	Positive	Beta, Delta, and Omicron	[109]
3	Viral vectors HuAd and ChAd	BALB/c and h ACE-II mice	S1 domain, nucleocapsid and RdRp	One, 5 × 107 PFU, IM or IN	IgG and IgA Ab IFN-γ	Positive	Alpha and Beta	[110]
4	RNA mRNA	HLA-A2.1 transgenic mice Syrian hamsters	Nucleocapsid, membrane and NSPs	Two, 3 µg BNT162b4	IFN-γ CD107a	Positive	Delta and Omicron BA.1	[111]
5	Viral vector lentiviral	h ACE-II-KI mice	Peptides of spike, nucleocapsid and ORF1	Two, 1 × 106 transduced cells. IV	IFN-γ and TNF-α	Positive	Omicron	[112]

IP, intraperitoneal; IM, intramuscular; IT, intratracheal; SC, subcutaneous; IV, intravenous; LN, lymph node; UD, undetermined.