. 2017 Jul 19;85(8):e00102-17. doi: 10.1128/IAI.00102-17

TABLE 2.

Experiments demonstrating that vaccination with the batA KO mutant strain provides protective immunity against aerosol challenge with lethal doses of WT organisms

No. of independent experiments	Vaccine^a	WT agent used in challenge^b	Total no. of mice challenged	% survival^c		% sterile immunity^d
No. of independent experiments	Vaccine^a	WT agent used in challenge^b	Total no. of mice challenged	Acute infection	Chronic infection	% sterile immunity^d
11	batA KO	B. mallei ATCC 23344	99	73	56	0
11	Naive	B. mallei ATCC 23344	94	4	2	0
8	batA KO	B. pseudomallei 1026b	82	71	67	62
8	Naive	B. pseudomallei 1026b	74	0	0	0
4	batA KO	B. pseudomallei K96243	33	100	85	57
4	Naive	B. pseudomallei K96243	27	11	4	0

Mice were vaccinated intratracheally with 10⁴ CFU of the batA KO mutant strain using a Microsprayer.

Thirty to 45 days postvaccination, mice were back-challenged intratracheally with lethal doses of WT bacteria (∼10 LD₅₀ of WT B. mallei ATCC 23344 and ∼5 LD₅₀ of B. pseudomallei 1026b and K96243) using a Microsprayer device. Age- and weight-matched naive mice were used as controls.

Acute infection, 1 to 10 days postchallenge; chronic infection, 11 to 55 days postchallenge.

The livers, spleens, and lungs of survivors were collected, homogenized, diluted, and plated onto agar medium to determine whether the tissues were colonized with WT bacteria.