title: Efficient monitoring of the blood-stage infection in a malaria rodent model by the rotating-crystal magneto-optical method.
abstract: Intense research efforts have been focused on the improvement of the efficiency and sensitivity of malaria diagnostics, especially in resource-limited settings for the detection of asymptomatic infections. Our recently developed magneto-optical (MO) method allows the accurate quantification of malaria pigment crystals (hemozoin) in blood by their magnetically induced rotation. First evaluations of the method using β-hematin crystals and in vitro P. falciparum cultures implied its potential for high-sensitivity malaria diagnosis. To further investigate this potential, here we study the performance of the method in monitoring the in vivo onset and progression of the blood-stage infection in a rodent malaria model. Our results show that the MO method can detect the first generation of intraerythrocytic P. berghei parasites 66-76 hours after sporozoite injection, demonstrating similar sensitivity to Giesma-stained light microscopy and exceeding that of flow cytometric techniques. Magneto-optical measurements performed during and after the treatment of P. berghei infections revealed that both the follow up under treatment and the detection of later reinfections are feasible with this new technique. The present study demonstrates that the MO method - besides being label and reagent-free, automated and rapid - has a high in vivo sensitivity and is ready for in-field evaluation.
authors.affiliation: Department of Physics, Budapest University of Technology and Economics and MTA-BME Lendület Magneto-optical Spectroscopy Research Group, 1111 Budapest, Hungary.
authors.forename: Ágnes
authors.initials: Á
authors.lastname: Orbán
authors.affiliation: Instituto de Medicina Molecular, Faculdade de Medicina Universidade de Lisboa, 1649-028 Lisbon, Portugal.
authors.forename: Maria
authors.initials: M
authors.lastname: Rebelo
authors.affiliation: Department of Physics, Budapest University of Technology and Economics and MTA-BME Lendület Magneto-optical Spectroscopy Research Group, 1111 Budapest, Hungary.
authors.forename: Petra
authors.initials: P
authors.lastname: Molnár
authors.affiliation: Instituto de Medicina Molecular, Faculdade de Medicina Universidade de Lisboa, 1649-028 Lisbon, Portugal.
authors.forename: Inês S
authors.initials: IS
authors.lastname: Albuquerque
authors.affiliation: Department of Physics, Budapest University of Technology and Economics and MTA-BME Lendület Magneto-optical Spectroscopy Research Group, 1111 Budapest, Hungary.
authors.forename: Adam
authors.initials: A
authors.lastname: Butykai
authors.affiliation: Department of Physics, Budapest University of Technology and Economics and MTA-BME Lendület Magneto-optical Spectroscopy Research Group, 1111 Budapest, Hungary.
authors.forename: István
authors.initials: I
authors.lastname: Kézsmárki
mesh_terms: D000818:Animals; D000852:Anopheles / Q000469:parasitology; D016054:DNA, Protozoan / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D004195:Disease Models, Animal; D005260:Female; D005434:Flow Cytometry / Q000379:methods; D006420:Hemeproteins / Q000235:genetics / Q000378:metabolism; D008018:Life Cycle Stages; D008288:Malaria / Q000175:diagnosis* / Q000469:parasitology / Q000662:veterinary; D051379:Mice; D008807:Mice, Inbred BALB C; D008853:Microscopy / Q000295:instrumentation / Q000379:methods*; D010962:Plasmodium berghei / Q000254:growth & development / Q000378:metabolism / Q000472:pathogenicity; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D016054:DNA, Protozoan; D006420:Hemeproteins; D015800:Protozoan Proteins; C020753:hemozoin