title: Human recombinant antibodies against Plasmodium falciparum merozoite surface protein 3 cloned from peripheral blood leukocytes of individuals with immunity to malaria demonstrate antiparasitic properties.
abstract: Immunoglobulins from individuals with immunity to malaria have a strong antiparasitic effect when transferred to Plasmodium falciparum malaria infected patients. One prominent target of antiparasitic antibodies is the merozoite surface antigen 3 (MSP-3). We have investigated the antibody response against MSP-3 residues 194 to 257 (MSP-3(194-257)) on the molecular level. mRNA from peripheral blood leukocytes from clinically immune individuals was used as a source of Fab (fragment antibody) genes. A Fab-phage display library was made, and three distinct antibodies designated RAM1, RAM2, and RAM3 were isolated by panning. Immunoglobulin G1 (IgG1) and IgG3 full-length antibodies have been produced in CHO cells. Reactivity with the native parasite protein was demonstrated by immunofluorescence microscopy, flow cytometry, and immunoblotting. Furthermore, the antiparasitic effect of RAM1 has been tested in vitro in an antibody-dependent cellular inhibition (ADCI) assay. Both the IgG1 and the IgG3 versions of the antibody show an inhibitory effect on parasite growth.
authors.affiliation: H:S Blodbanken KI2033, Copenhagen University Hospital, DK-2100 Copenhagen, Denmark. RL@Brygge.dk.
authors.forename: Rasmus
authors.initials: R
authors.lastname: Lundquist
authors.forename: Leif Kofoed
authors.initials: LK
authors.lastname: Nielsen
authors.forename: Ali
authors.initials: A
authors.lastname: Jafarshad
authors.forename: Daw
authors.initials: D
authors.lastname: Soesoe
authors.forename: Lars Harder
authors.initials: LH
authors.lastname: Christensen
authors.forename: Pierre
authors.initials: P
authors.lastname: Druilhe
authors.forename: Morten Hanefeld
authors.initials: MH
authors.lastname: Dziegiel
mesh_terms: D000328:Adult; D000595:Amino Acid Sequence; D000913:Antibodies, Protozoan / Q000276:immunology*; D000953:Antigens, Protozoan / Q000276:immunology*; D015153:Blotting, Western; D004797:Enzyme-Linked Immunosorbent Assay; D018604:Epitope Mapping; D005434:Flow Cytometry; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000276:immunology; D007074:Immunoglobulin G / Q000145:classification / Q000276:immunology; D007962:Leukocytes / Q000378:metabolism*; D008288:Malaria / Q000276:immunology*; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D019151:Peptide Library; D015800:Protozoan Proteins / Q000276:immunology*; D011994:Recombinant Proteins / Q000276:immunology
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D007140:Immunoglobulin Fab Fragments; D007074:Immunoglobulin G; D019151:Peptide Library; D015800:Protozoan Proteins; D011994:Recombinant Proteins; C089133:merozoite surface protein 3, Plasmodium