Table 1.

The comparison of outcomes in each hACE2 Tg mouse model to SARS-CoV infection

	K18-hACE2 [66, 67]	AC70, AC22, and AC63 [59, 68]	HFH4-ACE2 [69]	Mouse ACE2 promoter-driven hACE2 Tg mice [70]
Promoter	Human K18 promoter	CAG promoter	Human HFH4 promoter	Mouse ACE2 promoter
Parental mice of zygotes	(C57BL/6J × SJL/J) F2	(C57BL/6J × C3H/HeJ) F1	(C3H × C57BL/6) F1	ICR
Viral strains	Urbani	Urbani	Urbani	PUMC01
TCID50aof SARS-CoV	1.6 × 104b	AC70: 103 AC22: 106 AC63: 106	7 × 104c	105
Mortality (%)	Line 1: 100 Line 2: 100 Line 3: 100	AC70: 100 AC22: 0 AC63: 0	100	0
Survival days (p.i.)	Line 1: 2–5 Line 2: 3–4 Line 3: 5–7	AC70: 4–8 AC22: n.a.d AC63: n.a.	5–6	n.a.

^aTCID50 50% tissue culture infective dose

^bThe viral dosage used in the study, 2.3 × 10⁴ plaque-forming units (PFU), was converted to the estimated TCID50 by the conversion TCID50 ≈ 0.7 PFU [71].

^cThe viral dosage used in the study, 10⁵ PFU, was converted to the estimated TCID50 by the conversion TCID50 ≈ 0.7 PFU [71].

^dNot applicable