Distinct physiological states of Plasmodium falciparum in malaria infected patients

Patients infected with Plasmodium falciparum sustain diverse disease outcome; we wanted to determine if parasites derived ex vivo have diverse biological states. To explore parasite in vivo biology we measured parasite steady state whole genome transcription using a previously reported custom made Affy array (Scrmalaria) based on the laboratory strain 3D7. Extensive bioinformatic analysis was carried out including cross species comparisions to yeast. For sample cluster analysis, a filtered gene list containing 3937 genes was generated by thresholding gene expression levels to a minimum of 50 EU and removing any genes that varied less than 3 fold or 100 EU across the dataset. To minimize potential effects of different dates of collection and hybridizations, the data was rank ordered by expression level and each gene was given an ordinal value. Keywords: ex vivo 43 symptomatic patients from Senegal with P. falciparum underwent venipuncture; parasite RNA was derived directly from this sample.