Whole genome expression profiling of artemsinin-resistant Plasmodium falciparum field isolates [ex vivo]

The objective of our study is to characterize gene expression signatures associated with in vivo artemisinin-resistance phenotype in this large-scale genome-wide association study. To achieve this goal, we employed microarray technology to establish the global gene expression profiles of isolates sampled from 1043 patients, of whom after treatment with ACTs (artemisinin combination therapy) displayed differential rates of parasite clearance. P. falciparum isolates were sampled from the whole blood of 1043 malaria-infected patients. Sampling was done across 14 field sites spanning across South East Asia (Pailin, Pursat, Preah Vihear, Rattanakiri in Cambodia; Mae Sot, Srisakhet, Khun Han, Ranong in Thailand; Shwe Kyin in Myanmar; Binh Phuoc in Vietnam; Attapeu in Laos), to Bangladesh and African DR Congo from 2010 to 2012. Of the 1043 isolates, ex vivo culturing of 19 Pailin, Cambodian isolates were carried out and samples were harvested every 8 hours over the the 48 hour intraerythrocytic developmental cycle (IDC). RNA were extracted and synthesis and amplification of target DNA was carried out as described in Bozdech, Z., S. Mok & A. P. Gupta, (2013) DNA microarray-based genome-wide analyses of Plasmodium parasites. Methods in molecular biology 923: 189-211 (PMID 22990779), to generate sufficient material for hybridizations against a common RNA reference pool of 3D7 strain using a microarray platform.