Oral Poster & Poster Presentation 9th Australasian Virology Society Meeting 2017

Expression of MicroRNA by Human Retinal Pigment Epithelial Cells in Response to Infection with Ebola Virus (#101)

Genevieve F Oliver 1 , Ayla V Orang 1 , Binoy Appukuttan 1 , Michael Z Michael 1 , Glenn A Marsh 2 , Justine R Smith 1
  1. Flinders University, Bedford Park, SOUTH AUSTRALIA, Australia
  2. Health and Biosecurity, Commonwealth Scientific and Industrial Research Organisation, Geelong, Victoria, Australia

Individuals who survive acute infection with Ebola virus (EBOV) frequently develop a chronic inflammatory syndrome that includes uveitis (inflammation inside the eye). Post-Ebola uveitis is associated with persistence of EBOV within the eye, and previous work from our group has identified the retinal pigment epithelium as a potential ocular reservoir for EBOV. We have observed substantial changes in pigment epithelial cell gene expression following viral infection; in the present work, we investigated changes in microRNA (miRNA) levels in EBOV-infected cells. Total RNA was extracted from TRIzol Reagent-lysed ARPE-19 human retinal pigment epithelial cells 24 hours following inoculation with EBOV or mock-infection (multiplicity of infection=5, n=3 cultures per condition). cDNA libraries were prepared using Illumina TruSeq Small RNA Library Preparation Kits, and RNA sequencing was performed on the Illumina NextSeq 500. The sequences were filtered using FASTQC Toolkit. Reads were aligned to Gencode GRCh38.p3 using BWA mapper, and assigned to miRBase annotations using HTSeq-count. DESeq2 was employed to identify miRNA that were differentially expressed between EBOV- and mock- infected human retinal pigment epithelial cells. Taking a standard definition of differential expression (false discovery rate, FDR < 0.05), 28 and 61 miRNA were significantly increased and decreased, respectively. Filtering more stringently for > 2-fold change and FDR < 0.001, 13 and 2 miRNA were increased and decreased. Review of function of the 15 highly induced or repressed miRNA indicated a broad range of regulatory activities including effects on innate and adaptive immune responses, metabolism, cell cycle progression, apoptosis and autophagy. Our findings indicate that human retinal pigment epithelial cells make multiple molecular adjustments in response to infection with EBOV. Future studies will focus on effects of induction or repression of specific miRNA in infected cells.