Laboratory Evaluation of Pregnancy Malaria Vaccine Candidates/In-vitro Testing of Pregnancy Malaria Vaccine Candidates

Malaria caused by Plasmodium falciparum continues to be a global problem with devastating consequences. Pregnancy malaria is associated with low birth weight (LBW), maternal anemia, and gestational hypertension; and both inflammation and the fetal response to infection may contribute to these poor outcomes. Pregnancy malaria (PM) is caused by P. falciparum-infected erythrocytes that bind to the placental receptor chondroitin sulfate A (CSA) and sequester in the placenta, where they cause disease and death for the mother and her offspring. Women become resistant to pregnancy malaria as they acquire antibodies that target surface proteins of placental parasites. Malaria vaccine candidates targeting the parasite s liver stage or blood stage may not protect pregnant women and their unborn children. The primary hypothesis in this study is that antibodies raised in animals against recombinant pregnancy malaria vaccine candidates will have a similar functional activity as naturally acquired antibodies. Up to 2492 malaria-infected pregnant women will be recruited into a cross sectional study that will be conducted in Ouelessebougou and neighboring districts, Mali. Women presenting for antenatal visit at the health centers in Ouelessebougou District will be enrolled. Samples collected from the women will be used in in-vitro assays to assess the functional activity of immunoglobulin G (IgG) raised against pregnancy malaria vaccine candidates as the primary outcome of this study. For our secondary outcomes, we will examine functional activity of naturally acquired antibodies specific to the vaccine candidates. Functional activity by IgG to vaccine candidates will be compared to the activity obtained with control proteins using appropriate statistical methods, including adjustment for possible confounders such as parasite density in the assay, to determine if the candidates elicit the type of immune response observed in naturally exposed population.

• INCLUSION CRITERIA:

A study participant must satisfy the following criteria to be enrolled in this study:

• Pregnant women aged 15-25 years
• Able to provide consent for self
• Malaria positive by rapid diagnostic test (RDT)

Exclusion criteria

• Severe anemia defined as HGB<7 gr/dL, that may be worsened by 10 mL phlebotomy
• Conditions that in the judgment of the investigator could increase the risk to the volunteer
• Prior enrollment to the study during the same pregnancy