Implementation and continued validation of the malaria Plasmodium falciparum lactate dehydrogenase-based colorimetric assay for use in antiplasmodial drug screening

Patrick Valere Tsouh Fokou; Brice Mariscal Tchatat Tali; Darline Dize; Cedric Derick Jiatsa Mbouna; Cyrille Armel Njampa Ngansop; Rodrigue Keumoe; Lauve Rachel Yamthe Tchokouaha; Jean Claude Tchouankeu; Fanny Escudie; James Duffy; Fabrice Fekam Boyom

doi:10.1016/j.ab.2022.114669

Implementation and continued validation of the malaria Plasmodium falciparum lactate dehydrogenase-based colorimetric assay for use in antiplasmodial drug screening

Anal Biochem. 2022 Jul 1:648:114669. doi: 10.1016/j.ab.2022.114669. Epub 2022 Mar 20.

Affiliations

¹ Antimicrobial and Biocontrol Agents Unit, Laboratory for Phytobiochemistry and Medicinal Plants Studies, Faculty of Science, University of Yaoundé I, P.O. Box 812, Yaoundé, Cameroon; Department of Biochemistry, Faculty of Science, University of Bamenda, PO Box 39, Bambili, Bamenda, Cameroon.
² Antimicrobial and Biocontrol Agents Unit, Laboratory for Phytobiochemistry and Medicinal Plants Studies, Faculty of Science, University of Yaoundé I, P.O. Box 812, Yaoundé, Cameroon.
³ Antimicrobial and Biocontrol Agents Unit, Laboratory for Phytobiochemistry and Medicinal Plants Studies, Faculty of Science, University of Yaoundé I, P.O. Box 812, Yaoundé, Cameroon; Institute for Medical Research and Medicinal Plants Studies (IMPM), Yaoundé, P.O. Box 6163, Yaoundé, Cameroon.
⁴ Laboratory of Natural Products and Organic Synthesis, Faculty of Science, University of Yaoundé I, P.O. Box 812, Yaoundé, Cameroon.
⁵ Medicines for Malaria Venture, PO Box 1826, 20, Route de Pré-Bois, 1215, Geneva 15, Switzerland.
⁶ Antimicrobial and Biocontrol Agents Unit, Laboratory for Phytobiochemistry and Medicinal Plants Studies, Faculty of Science, University of Yaoundé I, P.O. Box 812, Yaoundé, Cameroon. Electronic address: fabrice.boyom@fulbrightmail.org.

PMID: 35321819
DOI: 10.1016/j.ab.2022.114669

Abstract

Antimalarial drug discovery has been facilitated by the development of various in vitro drug susceptibility testing methods suitable for medium-throughput or high-throughput campaigns. Among many, the Plasmodium falciparum lactate dehydrogenase (PfLDH) assay has acceptable demand on equipment, labour, technical skills and affordability and offers a good opportunity for scientists in low- and middle-income countries to participate in the global effort of discovering future antimalarial drugs. Hence, to enable our search for novel antimalarial drugs, we implemented and examined assay conditions and validated the PfLDH-based method in our laboratory using a reference set of standard antimalarial drugs with known activity against Plasmodium falciparum strains. The PfLDH assay revealed acceptable linearity profiles of R² = 0.97 and 0.92 for Pf3D7 and PfDd2, respectively, achieved at 2% parasitaemia and 1% haematocrit. The detection and quantitation limits (DL and QL) of the PfLDH-based assay were 0.09% and 0.4% parasitemia, respectively. The assay showed an acceptable average Z-factor between 0.76 and 0.79 and was considerably robust. The average interassay reproducibility via percent coefficient of variation (%CV) was 5.47 between independent experiments. Overall, the PfLDH-based method produced a reliable and reproducible drug screening profile for in vitro assays in our setting. There were no significant interassay variability or hazards of other screening assays.

Keywords: Antiplasmodial; High throughput screening; Implementation; PfLDH assay; Validation.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Antimalarials* / pharmacology
Colorimetry
Drug Evaluation, Preclinical
Humans
L-Lactate Dehydrogenase
Malaria, Falciparum* / diagnosis
Malaria, Falciparum* / drug therapy
Microbial Sensitivity Tests
Mycobacterium tuberculosis*
Plasmodium falciparum
Plasmodium*
Reproducibility of Results

Substances

Antimalarials
L-Lactate Dehydrogenase