. 2017 Oct 12;12(10):e0186244. doi: 10.1371/journal.pone.0186244

Table 2. Lung viral titers in vaccinated mice after challenge with H5N2, H7N9 or H9N2 influenza viruses.

Vaccine group	Lung virus titer after H5N2 challenge, Log₁₀ TCID₅₀/ml	Lung virus titer after H7N9 challenge, Log₁₀ EID₅₀/ml	Lung virus titer after H9N2 challenge, Log₁₀ TCID₅₀/ml
ΔE1E3	3.9±0.57	4.9±0.27	6.2±0.5
H5HA	< 1.2^*	4.5±0.27	5.8±0.62
H7HA	3.5+0.35	<1.2^*	5.9±0.35
H9HA	3.7±0.43	4.7±0.54	< 1.2^*
H5ME	2.4±0.32^*	3.7±0.54^*	4.4±0.6^*

Mice (5 mice/group) were immunized twice with H5HA, H7HA, H9HA, H5ME, or ΔE1E3 at an interval of three weeks. Three weeks after the final immunization, mice were challenged with one of the following viruses: H5N2, H7N9 or H9N2. Three days after the challenged, mice were euthanized and the lungs were harvested to determine lung virus titers. The data are shown as mean Log₁₀ TCID₅₀±SD (for H9N2 and H5N2) or mean Log₁₀ EID₅₀±SD (for H7N9). The detection limit of lung viral titer was <1.2 Log₁₀ TCID₅₀/ml (for H9N2 and H5N2) or <1.2 Log₁₀ EID₅₀/ml (for H7N9) [indicated as <1.2].

*P≤ 0.05 as compared to the ΔE1E3 control. H5HA, Ad-H5HA; H7HA, Ad-H7HA; H9HA, Ad-H9HA,; H5ME, Ad-H5ME; ΔE1E3, Ad-ΔE1E3; TCID₅₀, tissue culture infectious dose 50; EID₅₀, egg infectious dose 50; SD, standard deviation; H5N2, A/chukar/MN/145917/1998(H5N2); H7N9, A/goose/Nebraska/17097/2011(H7N9); H9N2, A/Hong Kong/1073/ 1999(H9N2).