Quantification of malaria antigens PfHRP2 and pLDH by quantitative suspension array technology in whole blood, dried blood spot and plasma

ABSTRACT: Background: Malaria diagnostics by rapid diagnostic test (RDT) relies primarily on the qualitative detection of Plasmodium falciparum histidine-rich protein 2 (PfHRP2) and Plasmodium spp lactate dehydrogenase (pLDH). As novel RDTs with increased sensitivity are being developed and implemented as point of care diagnostics, highly sensitive laboratory-based assays are needed for evaluating RDT performance. Here, a quantitative suspension array technology (qSAT) was developed, validated and applied for the simultaneous detection of PfHRP2 and pLDH in a variety of biological samples (whole blood, plasma and dried blood spots) from individuals living in different endemic countries. Results: The qSAT was specific for the target antigens, with analytical ranges of 6.8 to 762.8 pg/ml for PfHRP2 and 78.1 to 17076.6 pg/ml for P. falciparum LDH (Pf-LDH). The assay detected Plasmodium vivax LDH (Pv-LDH) at a lower sensitivity than Pf-LDH (analytical range of 1093.20 to 187288.5 pg/ml). Both PfHRP2 and pLDH levels determined using the qSAT showed to positively correlate with parasite densities determined by quantitative PCR (Spearman r = 0.59 and 0.75, respectively) as well as microscopy (Spearman r = 0.40 and 0.75, respectively), suggesting the assay to be a good predictor of parasite density. Conclusion: This immunoassay can be used as a reference test for the detection and quantification of PfHRP2 and pLDH, and could serve for external validation of RDT performance, to determine antigen persistence after parasite clearance, as well as a complementary tool to assess malaria burden in endemic settings. Keywords: Histidine-rich protein 2; Luminex; Malaria; Parasite lactate dehydrogenase; Quantitative suspension array technology; Rapid diagnostic test.

• Autores: Vásquez Cardona, Ana María; Ding, Xavier C.; Faye, Babacar; Gamboa, Dionicia; González, Raquel; Incardona, Sandra; Jiménez, Alfons; Macete, Eusebio; Martiáñe Vendrell, Xavier; Mayor, Alfredo; Menéndez, Clara; Campillo, Ana; Oyibo, Wellington; Torres, Katherine
• Tipo de recurso: Article of investigation
• Fecha de publicación: 2020
• Institución: Universidad de Antioquia
• Repositorio: Repositorio UdeA
• Idioma: eng
• OAI Identifier: oai:bibliotecadigital.udea.edu.co:10495/42052
• Acceso en línea: https://hdl.handle.net/10495/42052
• Palabra clave: Antígenos de Protozoos; Antigens, Protozoan; Secuenciación de Nucleótidos de Alto Rendimiento; High-Throughput Nucleotide Sequencing; L-Lactato Deshidrogenasa; L-Lactate Dehydrogenase; Malaria Falciparum; Malaria, Falciparum; Malaria Vivax; Malaria, Vivax; Biotina; Biotin; Calibración; Calibration; Microesferas; Microspheres; Parasitemia; Reacción en Cadena en Tiempo Real de la Polimerasa; Real-Time Polymerase Chain Reaction; Proteínas Protozoarias; Protozoan Proteins; https://id.nlm.nih.gov/mesh/D000953; https://id.nlm.nih.gov/mesh/D059014; https://id.nlm.nih.gov/mesh/D007770; https://id.nlm.nih.gov/mesh/D016778; https://id.nlm.nih.gov/mesh/D016780; https://id.nlm.nih.gov/mesh/D001710; https://id.nlm.nih.gov/mesh/D002138; https://id.nlm.nih.gov/mesh/D008863; https://id.nlm.nih.gov/mesh/D018512; https://id.nlm.nih.gov/mesh/D060888; https://id.nlm.nih.gov/mesh/D015800
• Rights: openAccess
• License: http://creativecommons.org/licenses/by/2.5/co/