A highly infectious Plasmodium yoelii parasite, bearing Plasmodium falciparum circumsporozoite protein

Table 2 Titration of the infectivity of PfCSP/Py Spz through intravenous injection

	# of Spz injected iv	Day 3 post challenge^a	Day 4 post challenge	Day 5 post challenge
Wild-type P. yoelii	450	0/5	5/5	5/5
	150	0/5	5/5	5/5
	50	0/5	4/5	5/5
PfCSP/Py	450	0/5	5/5	5/5
	150	0/5	5/5	5/5
	50	0/5	5/5	5/5

^aNumber of infected mice/number of challenged mice. Infection was defined as the observation of blood stage parasites in thin blood smears by Giemsa staining