Figure 4. Expression of immunomodulatory gene transcripts in human retinal pigment epithelial cells. After transfection with Zaire ebolavirus viral protein 24 (VP24) or no-insert control (NI) expression plasmid for 48 h, followed by polyinosinic-polycytidylic acid (poly I:C) for an additional 4 or 24 h (hours), cellular levels of five immunomodulatory gene transcripts were measured by quantitative polymerase chain reaction and normalized to two stable reference genes (glyceraldehyde 3-phosphate dehydrogenase [GAPDH] and peptidylprolyl isomerase A [PPIA]). An additional control replacing poly I:C with water was included for the 4-h condition. In All Isolate graphs, circles represent mean expression in individual isolates, crossbars indicate mean, and error bars indicate standard deviation (n = 4 isolates/condition). In Isolate 1–4 graphs, bars indicate mean normalized expression, and error bars indicate standard deviation (n = 4 replicates/condition). CD274, CD274 molecule (programmed death-ligand 1); IL1RN, interleukin 1 receptor antagonist; ND, transcript not detectable in ≥2 of 4 replicates; ns, not significant; PDCD1LG2, programmed cell death 1 ligand 2; TGFB1, transforming growth factor beta 1; TGFB2, transforming growth factor beta 2. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001.