Total RNA and MicroRNA Transcriptomic Responses of Human Retinal Müller Glial Cells to Infection with

Purpose: Ocular toxoplasmosis, caused by infection with Design: Laboratory-based study. Samples: Human retinal Müller glial cells infected with Methods: Monolayers of Müller glial cells isolated from human retina (6 donor eye pairs) were infected for 24 hours with GT1 or GPHT strain Main Outcome Measures: Total and small RNA transcriptomes. Results: 6.3% of total RNA and 2.4% of small RNA changed in GT1-infected cells (582 upregulated and 210 downregulated transcripts and 20 upregulated microRNAs) versus 4.3% of total RNA and 1.5% of small RNA in GPHT-infected cells (400 upregulated and 137 downregulated transcripts and 12 upregulated microRNAs). Seventy-six transcripts and 4 microRNAs were different between strains; most were increased by both, but GT1 induced higher levels than GPHT. Enriched pathways and ontologies were dominated by DNA replication and intracellular metabolic activities, and the immune response for GT1 and GPHT. Seven of 8 transcription factor binding sites were shared for GT1 and GPHT infections, all overexpressed, including sites for p65/RELA and E2F family members. Across the strains, miR-18a-5p was the most connected microRNA in predicted mRNA target networks. Conclusions: This work demonstrates that human retinal Müller glial cells shift to a proliferative and inflammatory phenotype when infected with Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.