TABLE 2.

Statistical comparisons of median survival times^a and survival rates^b

Immunization group	P value for the following groupc:
	PBS	NI-IgG	Indifferent MAb	PLY-7	PLY-4	PLY-5	2 MAbs	3 MAbs	Anti-PLY IgG
PBS		0.0003	0.0198	NS	<0.0001	NS	0.0002	<0.0001	<0.0001
NI-IgG	NS		ND	ND	ND	ND	ND	ND	0.0001
Indifferent MAb	NS	ND		NS	0.0048	NS	0.0288	0.0010	ND
PLY-7	NS	ND	NS		ND	ND	ND	0.0007	ND
PLY-4	NS	ND	NS	ND		ND	NS	0.0443	0.0032
PLY-5	NS	ND	NS	ND	ND		ND	<0.0001	ND
2 MAbs	0.0033	ND	NS	NS	NS	0.0197		NS	NS
3 MAbs	0.0004	ND	0.0138	0.0407	0.0138	0.0033	NS		NS
Anti-PLY IgG	<0.0001	<0.0001	0.0003	0.0003	<0.0001	<0.0001	NS	NS

^aDifferences in median survival times between groups of mice protected with the indicated antibody were analyzed by using the Mann-Whitney U test.

^bDifferences in survival rates between groups of mice were analyzed by using the Fisher exact test.

^c2 MAbs: PLY-4 and PLY-7; 3 MAbs: PLY-4, PLY-7, and PLY-5. NS, not significant; ND, not determined.