TABLE 2.

Immunogenicity and protective efficacy of the III-α9r conjugate vaccine in mice^a

Immunizing antigen	Dose of immunization (μg/mouse)b	No. of pups alive/total no. of pups (% survival)c	α9r-specific IgG titerd
III-α9r	5	16/26 (62)*	400
III-α9r	10	15/35 (37)**	200
III-α9r	20	2/32 (6)***	600
α9r (positive control)	10	18/31 (58)	1,200
Saline (negative control)	0	2/29 (2)	200

^aProtection of neonatal mice against α-positive GBS challenge was tested. 

^bMice were immunized at days 0 and 21. 

^cPups were challenged with GBS strain A909. Compared to saline, P values were as follows: *, <0.0001; **, 0.0014; and ***, 1.000. Compared to α9r, P values were as follows: *, 1.000; **, 0.3240; and ***, <0.0001. 

^dBlood was drawn at day 60; sera from three mice were pooled.