TABLE 1.

Adjuvant effects of LT_R192G on the serum anti-flagellin IgG and secreted IgA responses in BALB/c mice immunized with attenuated S. enterica serovar Dublin ICB5 delivered via different routes

Vaccine	Immunization routea	Antibody titerb
		Serum IgG		Fecal IgA		Lung wash IgA
		FLA	LT	FLA	LT	FLA	LT
ICB5	i.p.	32,180 ± 2,574	ND	ND	ND	ND	ND
	Oral	50 ± 6	<2	<2	<2	ND	ND
	Nasal	16 ± 2	<2	ND	<2	82 ± 9	ND
ICB5 plus LT	Oral	51 ± 4	10,683 ± 961	3 ± 1	41 ± 4	ND	ND
	Nasal	10 ± 2	2 × 106 ± 1.6 × 104	ND	ND	104 ± 12	8,000 ± 796

^aImmunizations were carried out with three doses of 10¹⁰ CFU (p.o.) or 10⁷ CFU (i.n. or i.p.) on days 0, 21, and 35. Serum, fecal, and lung wash samples were collected 1 week after the last immunization dose.

^bTiters were determined in ELISA plates treated with type d flagellin (FLA) or purified LT_R192G (LT). Values are means of endpoint titers ± SEM of serum pools prepared from each mouse group. Data are based on two independent experiments. ND, not done.