Figure 2. Multidimensional scaling of gene transcription in human retinal pigment epithelial cells. Plots show log₂ fold differences for 19 immune response–related (antiviral, immunomodulatory, and proinflammatory) gene transcripts measured by quantitative polymerase chain reaction after transfection with Zaire ebolavirus viral protein 24 (VP24, red) or no-insert control (blue) expression plasmid for 48 h, followed by polyinosinic-polycytidylic acid (poly I:C) for an additional 4 or 24 h (hours). Symbols represent individual isolates, indicating gender and age at death dichotomized around the median of 62 years (yrs). M, male; F, female; PC (%), principal component (% variation).