title: Critical evaluation of different methods for measuring the functional activity of antibodies against malaria blood stage antigens.
abstract: Antibodies are thought to be the primary immune effectors in the defense against erythrocytic stage Plasmodium falciparum. Thus, malaria vaccines directed to blood stages of infection are evaluated based on their ability to induce antibodies with anti-parasite activity. Such antibodies may have different effector functions (e.g., inhibition of invasion or inhibition of parasite growth/development) depending on the target antigen. We evaluated four methods with regards to their ability to differentiate between invasion and/or growth inhibitory activities of antibodies specific for two distinct blood stage antigens: AMA1 and MSP1(42). We conclude that antibodies induced by these vaccine candidates have different modes of action that vary not only by the antigen, but also by the strain of parasite being tested. Analysis based on parasitemia and viability was essential for defining the full range of anti-parasite activities in immune sera.
authors.affiliation: Department of Immunology, CD&I, Walter Reed Army Institute of Research, Silver Spring, Maryland 20910, USA. elke.bergmannleitner@us.army.mil
authors.forename: Elke S
authors.initials: ES
authors.lastname: Bergmann-Leitner
authors.forename: Elizabeth H
authors.initials: EH
authors.lastname: Duncan
authors.forename: Gregory E
authors.initials: GE
authors.lastname: Mullen
authors.forename: John Robert
authors.initials: JR
authors.lastname: Burge
authors.forename: Farhat
authors.initials: F
authors.lastname: Khan
authors.forename: Carole A
authors.initials: CA
authors.lastname: Long
authors.forename: Evelina
authors.initials: E
authors.lastname: Angov
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Lyon
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood* / Q000276:immunology; D000953:Antigens, Protozoan / Q000097:blood* / Q000276:immunology; D004396:Coloring Agents; D005434:Flow Cytometry; D006801:Humans; D007106:Immune Sera; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D017780:Malaria Vaccines / Q000276:immunology; D010963:Plasmodium falciparum / Q000276:immunology*
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D004396:Coloring Agents; D007106:Immune Sera; D017780:Malaria Vaccines; D007770:L-Lactate Dehydrogenase