Expression of full-length Plasmodium falciparum P48/45 in P. berghei blood stages: A method to express and evaluate vaccine antigens

• Published in: Molecular and biochemical parasitology 2018-09, Vol.224, p.44-49
• Main Authors: Othman, Ahmad Syibli, Lin, Jing-wen, Franke-Fayard, Blandine M., Kroeze, Hans, van Pul, Fiona J.A., Chevalley-Maurel, Séverine, Ramesar, Jai, Marin-Mogollon, Catherin, Jore, Matthijs M., Morin, Merribeth J., Long, Carole A., Sauerwein, Robert, Birkett, Ashley, Miura, Kazutoyo, Janse, Chris J., Khan, Shahid M.
• Format: Article
• Language: English
• Subjects: Animals; Antigens, Protozoan - biosynthesis; Antigens, Protozoan - genetics; Antigens, Protozoan - immunology; Disease Models, Animal; Disease Transmission, Infectious - prevention & control; Gene Expression; Immunization; Malaria - prevention & control; Malaria Vaccines - immunology; Membrane Proteins - biosynthesis; Membrane Proteins - genetics; Membrane Proteins - immunology; Mice; Pfs48/45; Plasmodium; Plasmodium berghei - genetics; Plasmodium falciparum - genetics; Promoter Regions, Genetic; Recombinant Proteins - biosynthesis; Recombinant Proteins - genetics; Recombinant Proteins - immunology; Standard membrane feeding; Transgene-expression; Transgenes; Transmission blocking
• ISSN: 0166-6851; 1872-9428
• DOI: 10.1016/j.molbiopara.2018.07.009

•Full-length Pfs48/45 protein is efficiently expressed in blood stages of P. berghei.•P. berghei blood-stage expressed Pfs48/45 retain conformational epitopes.•Strong transmission blocking immunity is induced by P. berghei expressed Pfs48/45. The transmission-blocking vaccine candidate Pfs48/45 from the human malaria parasite Plasmodium falciparum is known to be difficult to express in heterologous systems, either as full-length protein or as correctly folded protein fragments that retain conformational epitopes. In this study we express full-length Pfs48/45 in the rodent parasite P. berghei. Pfs48/45 is expressed as a transgene under control of the strong P. berghei schizont-specific msp1 gene promoter (Pfs48/45@PbMSP1). Pfs48/45@PbMSP1 schizont-infected red blood cells produced full-length Pfs48/45 and the structural integrity of Pfs48/45 was confirmed using a panel of conformation-specific monoclonal antibodies that bind to different Pfs48/45 epitopes. Sera from mice immunized with transgenic Pfs48/45@PbMSP1 schizonts showed strong transmission-reducing activity in mosquitoes infected with P. falciparum using standard membrane feeding. These results demonstrate that transgenic rodent malaria parasites expressing human malaria antigens may be used as means to evaluate immunogenicity and functionality of difficult to express malaria vaccine candidate antigens.