• INCLUSION CRITERIA:

Males or females between 18 and 50 years, inclusive.

Available for the duration of the trial (34 weeks)

Willingness to participate in the study as evidenced by signing the informed consent document.

Weighing at least 110 pounds.

EXCLUSION CRITERIA:

Age less than 18 years because insufficient data are available in adults to judge potential risk in children.

Pregnancy as determined by a positive urine Beta-hCG (if female).

Participant unwilling to use reliable contraception methods (condoms or oral contraceptives) for the duration of the trial (if female).

Currently lactating and breast-feeding (if female).

Participant unwilling to undergo apheresis.

Evidence of clinically significant neurologic, cardiac, pulmonary, hepatic, rheumatologic, autoimmune, or renal disease by history, physical examination, and/or laboratory studies including urinalysis.

Behavioral, cognitive, or psychiatric disease that in the opinion of the investigator affects the ability of the volunteer to understand and cooperate with the study protocol.

Laboratory evidence of liver disease (aspartate aminotransferase AST greater than the upper limit of normal of the testing laboratory and/or total bilirubin levels greater than the upper limits of normal of the testing laboratory).

Laboratory evidence of renal disease (serum creatinine greater than the upper limit of normal of the testing laboratory).

Laboratory evidence of hematologic disease (absolute neutrophil count less than 1,500/mm(3); hemoglobin less than the lower limit of normal of the testing laboratory, by sex; or platelet count less than 140,000/mm(3).

Other condition that in the opinion of the investigator would jeopardize the safety or rights of a volunteer participating in the trial or would render the subject unable to comply with the protocol.

Participation in another investigational vaccine or drug trial within 30 days of enrolling in this study, or while this study is ongoing.

Volunteer has had medical, occupational, or family problems as a result of alcohol or illicit drug use during the past 12 months.

History of a severe allergic reaction or anaphylaxis to drugs or foods.

Asthma that has resulted in an emergency room visit or hospitalization within the last 6 months.

Positive ELISA and confirmatory Western blot tests for HIV-1.

Positive ELISA and standard confirmatory tests for HCV.

Positive HBsAg by ELISA.

Known immunodeficiency syndrome.

Use of corticosteroids (excluding topical or nasal) or immunosuppressive drugs within 30 days of enrolling in this study or while the study is ongoing.

Receipt of a live vaccine within past 4 weeks or a killed vaccine within past 2 weeks prior to entry into the study.

History of a surgical splenectomy.

Receipt of blood products within the past 6 months.

Previous receipt of an investigational malaria vaccine.

Receipt of antimalarial prophylaxis during the past 12 months.

Prior malaria infection.

Travel to a malaria-endemic country during the past 12 months or planned travel to a malaria-endemic country during the course of the study.

History of a known allergy to nickel.

History of known allergy to yeast.