Figure 10. Schematic summary of the effects of viral dsRNA on the gene expression of cultured human RPE cells. Activation of the pattern recognition receptor TLR3 by dsRNA results in activation of various signal transduction pathways (e.g., ERK1/2, p38 MAPK, JNK, PI3K-Akt) which are differentially involved in inducing the gene expression of TLR3, inflammatory factors such as TNFα and IL-1β, complement factors such as CFB, and the angiogenic factor bFGF. The expression of various genes is differentially induced by the transcription factors HIF-1, NF-κB, and STAT3. In addition to gene expression induction, dsRNA induces the secretion of inflammatory (TNFα) and angiogenic factors (bFGF) from the cells. It remains to be determined whether dsRNA also induces a secretion of further proteins, such as CFB, IL-1β, and MCP-1.