Table 1.

Differential recombinant HBHA boosting effect of BCG-induced protective immunity in BALB/c newborn mice against M. tuberculosis H37Rv infection as measured by reduced bacterial load in spleen and lungs.

Vaccine	Lung CFUsa	Lung protection		Spleen CFUsa	Spleen protection
		Versus			Versus
		Control	BCG		Control	BCG
Controlb	6.24 ± 0.25			5.04 ± 0.29
BCGb	5.24 ± 0.40	1.0*		4.15 ± 0.55	0.89*
BCG-rHBHAb	3.98 ± 0.11	2.26*	1.26**	3.72 ± 0.12	1.32*	0.43**
Controlc	4.50 ± 0.71			4.50 ± 0.46
BCGc	3.91 ± 0.28	0.59*		3.87 ± 0.34	0.63*
BCG-rHBHAc	3.91 ± 0.47	0.59*		3.15 ± 0.71	1.35*	0.72**

^aData are represented as mean ± standard deviations of the log₁₀-transformed bacterial (CFUs) of M. tuberculosis per organ; ^bintranasal challenge; ^caerosol challenge. Protection is calculated with respect to control of vaccination (BCG) and with respect to PBS-immunized newborn mice (control). The data reported are *significant at P < 0.05 with respect to control mice and **significant at P < 0.05 with respect to BCG control of vaccination with no boost. One representative of a total of two independent experiments is shown.