High content live cell imaging for the discovery of new antimalarial marine natural products.
BACKGROUND
The human malaria parasite remains a burden in developing nations. It is responsible for up to one million deaths a year, a number that could rise due to increasing multi-drug resistance to all antimalarial drugs currently available. Therefore, there is an urgent need for the discovery of new drug therapies. Recently, our laboratory developed a simple one-step fluorescence-based live cell-imaging assay to integrate the complex biology of the human malaria parasite into drug discovery. Here we used our newly developed live cell-imaging platform to discover novel marine natural products and their cellular phenotypic effects against the most lethal malaria parasite, Plasmodium falciparum.


METHODS
A high content live cell imaging platform was used to screen marine extracts effects on malaria. Parasites were grown in vitro in the presence of extracts, stained with RNA sensitive dye, and imaged at timed intervals with the BD Pathway HT automated confocal microscope.


RESULTS
Image analysis validated our new methodology at a larger scale level and revealed potential antimalarial activity of selected extracts with a minimal cytotoxic effect on host red blood cells. To further validate our assay, we investigated parasite's phenotypes when incubated with the purified bioactive natural product bromophycolide A. We show that bromophycolide A has a strong and specific morphological effect on parasites, similar to the ones observed from the initial extracts.


CONCLUSIONS
Collectively, our results show that high-content live cell-imaging (HCLCI) can be used to screen chemical libraries and identify parasite specific inhibitors with limited host cytotoxic effects. All together we provide new leads for the discovery of novel antimalarials.
Department of Cell Biology and Neuroscience, University of California Riverside, Riverside, CA 92521, USA.
Serena
S
Cervantes
Paige E
PE
Stout
Jacques
J
Prudhomme
Sebastian
S
Engel
Matthew
M
Bruton
Michael
M
Cervantes
David
D
Carter
Young
Y
Tae-Chang
Mark E
ME
Hay
William
W
Aalbersberg
Julia
J
Kubanek
Karine G
KG
Le Roch
D000962:Antimalarials / Q000302:isolation & purification* / Q000494:pharmacology; D001688:Biological Products / Q000302:isolation & purification* / Q000494:pharmacology; D003584:Cytological Techniques / Q000379:methods*; D004353:Drug Evaluation, Preclinical / Q000379:methods*; D004912:Erythrocytes / Q000469:parasitology; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D010963:Plasmodium falciparum / Q000187:drug effects* / Q000254:growth & development
D000962:Antimalarials; D001688:Biological Products