A chemical susceptibility profile of the Plasmodium falciparum transmission stages by complementary cell-based gametocyte assays
S D'Alessandro, G Camarda, Y Corbett… - Journal of …, 2016 - academic.oup.com
S D'Alessandro, G Camarda, Y Corbett, G Siciliano, S Parapini, L Cevenini, E Michelini…
Journal of Antimicrobial Chemotherapy, 2016•academic.oup.comObjectives As most available antimalarial drugs are ineffective against the Plasmodium
falciparum transmission stages, new drugs against the parasite's gametocytes are urgently
needed to combat malaria globally. The unique biology of gametocytes requires assays that
need to be specific, to faithfully monitor anti-gametocyte activity, and to be easy to perform,
cheap and scalable to high-throughput screening (HTS). Methods We developed an HTS
cell-based assay with P. falciparum gametocytes specifically expressing a potent luciferase …
falciparum transmission stages, new drugs against the parasite's gametocytes are urgently
needed to combat malaria globally. The unique biology of gametocytes requires assays that
need to be specific, to faithfully monitor anti-gametocyte activity, and to be easy to perform,
cheap and scalable to high-throughput screening (HTS). Methods We developed an HTS
cell-based assay with P. falciparum gametocytes specifically expressing a potent luciferase …
Objectives
As most available antimalarial drugs are ineffective against the Plasmodium falciparum transmission stages, new drugs against the parasite's gametocytes are urgently needed to combat malaria globally. The unique biology of gametocytes requires assays that need to be specific, to faithfully monitor anti-gametocyte activity, and to be easy to perform, cheap and scalable to high-throughput screening (HTS).
Methods
We developed an HTS cell-based assay with P. falciparum gametocytes specifically expressing a potent luciferase. To confirm HTS hit activity for several parasite genotypes, the luciferase assay and the gametocyte lactate dehydrogenase (LDH) assay, usable on any parasite isolate, were compared by screening antimalarial drugs and determining IC50 values of anti-gametocyte hits from the ‘Malaria Box’ against early- and late-stage gametocytes.
Results
Comparison of the two assays, conducted on the early and on late gametocyte stages, revealed an excellent correlation (R2 > 0.9) for the IC50 values obtained by the respective readouts. Differences in susceptibility to drugs and compounds between the two parasite developmental stages were consistently measured in both assays.
Conclusions
This work indicates that the luciferase and gametocyte LDH assays are interchangeable and that their specific advantages can be exploited to design an HTS pipeline leading to new transmission-blocking compounds. Results from these assays consistently defined a gametocyte chemical susceptibility profile, relevant to the planning of future drug discovery strategies.
Oxford University Press