Plasmodium berghei circumsporozoite protein encapsulated in oligomannose-coated liposomes confers protection against sporozoite infection in mice

Table 2 Effects of OML-based antigen immunization against P. berghei sporozoite challenge

Antigen	Immunization		Antibody titration*		Infected/total [1^st+ 2^ndtrials] (Number)	Parasitemia*	Protection^†(%)
	Dose	Boost	IgG1	IgG2a
OML-PbCSP	3 μg	2	10666.7 ± 3304.9^††	3466.7 ± 1573.1^††	5/11 [(2/5) + (3/6)]	6.40 ± 0.55	54% (P = 0.004)
OML-PbCSP	1 μg	2	4900.0 ± 2038.6^††	1200.0 ± 979.8^††	2/6	8.50 ± 2.10	66.7% (P = 0.002)
OML-PbCSP	3 μg	1	1733.3 ± 786.5^††	600.0 ± 219.1^††	5/6	6.50 ± 1.00	66.7% (P = 0.002)
OML-PbCSP	1 μg	1	533.3 ± 206.6^††	266.7 ± 103.3^††	4/6	6.60 ± 1.34	33.3% (P = 0.041)
PbCSP	3 μg	1	433.3 ± 196.6	166.7 ± 51.6	11/11 [(5/5) + (6/6)]	5.83 ± 0.98	0% (N.A.)
OML-PBS		2	0	0	10/11 [(5/5) + (5/6)]	5.50 ± 1.40	5.9% (P = 0.413)
None		0	0	0	11/11 [(5/5) + (6/6)]	5.09 ± 1.04	0%

*Antigen-specific IgG1 and IgG2a detected by ELISA with recombinant PbCSP l4 day after the last boost. Each value represents the mean antibody titer ± SD per mouse group.
*Each value represents tie mean day of parasitemia onset ± SD per mouse group.
^††Indicates a statistically significant difference between the antibody response of the OML-based antigen-immunized group to those of the corresponding group immunized with naked antigen.
^†Mice were scored as protected when parasitemia was not observed over a 30-day pariod.
^†Significant difference in protection rate as compared to none and as calculated by chi-test. NA.: Not applicable.
Results represent pooled data of two independent experiments.

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