title: Plant-based production of recombinant Plasmodium surface protein pf38 and evaluation of its potential as a vaccine candidate.
abstract: Pf38 is a surface protein of the malarial parasite Plasmodium falciparum. In this study, we produced and purified recombinant Pf38 and a fusion protein composed of red fluorescent protein and Pf38 (RFP-Pf38) using a transient expression system in the plant Nicotiana benthamiana. To our knowledge, this is the first description of the production of recombinant Pf38. To verify the quality of the recombinant Pf38, plasma from semi-immune African donors was used to confirm specific binding to Pf38. ELISA measurements revealed that immune responses to Pf38 in this African subset were comparable to reactivities to AMA-1 and MSP119. Pf38 and RFP-Pf38 were successfully used to immunise mice, although titres from these mice were low (on average 1∶11.000 and 1∶39.000, respectively). In immune fluorescence assays, the purified IgG fraction from the sera of immunised mice recognised Pf38 on the surface of schizonts, gametocytes, macrogametes and zygotes, but not sporozoites. Growth inhibition assays using αPf38 antibodies demonstrated strong inhibition (≥60%) of the growth of blood-stage P. falciparum. The development of zygotes was also effectively inhibited by αPf38 antibodies, as determined by the zygote development assay. Collectively, these results suggest that Pf38 is an interesting candidate for the development of a malaria vaccine.
authors.affiliation: Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Aachen, Germany.
authors.forename: Tatjana
authors.initials: T
authors.lastname: Feller
authors.forename: Pascal
authors.initials: P
authors.lastname: Thom
authors.forename: Natalie
authors.initials: N
authors.lastname: Koch
authors.forename: Holger
authors.initials: H
authors.lastname: Spiegel
authors.forename: Otchere
authors.initials: O
authors.lastname: Addai-Mensah
authors.forename: Rainer
authors.initials: R
authors.lastname: Fischer
authors.forename: Andreas
authors.initials: A
authors.lastname: Reimann
authors.forename: Gabriele
authors.initials: G
authors.lastname: Pradel
authors.forename: Rolf
authors.initials: R
authors.lastname: Fendel
authors.forename: Stefan
authors.initials: S
authors.lastname: Schillberg
authors.forename: Matthias
authors.initials: M
authors.lastname: Scheuermayer
authors.forename: Helga
authors.initials: H
authors.lastname: Schinkel
mesh_terms: D000818:Animals; D000953:Antigens, Protozoan / Q000235:genetics* / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D005455:Fluorescent Antibody Technique; D017780:Malaria Vaccines / Q000276:immunology*; D046549:Plantibodies / Q000235:genetics* / Q000276:immunology; D010963:Plasmodium falciparum / Q000254:growth & development / Q000276:immunology*; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D014026:Nicotiana / Q000235:genetics*
chemical_list: D000953:Antigens, Protozoan; D017780:Malaria Vaccines; C507528:Pf38 antigen, Plasmodium falciparum; D046549:Plantibodies; D011994:Recombinant Proteins