Table 1.

Protection of mice immunized with CAS or RAS against challenge with wild-type sporozoites

Group	Mouse strain	Immunizationa RAS/CAS × 103	Challengeb	Day of challenge	Sterile immunity?	Prepatent period (days)	No. protected (no. challenged)
							Controlc	CASd	RAS
1	BALB/c	50/20/20 (P.y.)	100 (P.y.)	10	yes	NAe	0 (8)	4 (4)	4 (4)
2	BALB/c	20 (P.y.)	100 (P.y.)	21	no	1.5f	0 (5)	0 (5)	0 (5)
3	BALB/c	50/20/20 (P.b.)	100 (P.y.)	10	yes	NA	0 (8)	4 (4)	4 (4)
4	BALB/c	50/20/20 (P.b.)	100 (P.y.)	21	no	<2g	0 (11)	0 (8)	0 (8)

^aGroups of mice were immunized with P. berghei ANKA (P.b.) or P. yoelii 17XNL (P.y.) control (vehicle-treated) sporozoites, CAS, or RAS as indicated, isolated from the same mosquito batches and were immunized at 7 day intervals.

^bGroups of mice were challenged with P. berghei ANKA or P. yoelii 17XNL wild-type sporozoites

^cNaïve, age-matched mice were used at the time of all immunizations and challenges.

^dStatistical analysis using Fisher exact test for comparison of Control and CAS groups gave p<0.002 for groups 1 and 3.

^eNA, not applicable.

^fNaïve, age-matched mice developed patent parasitemia 1.5 days p.i. in both the CAS and RAS groups.

^gAll mice showed patent parasitemia 2 days p.i.