Toll-like receptors (TLRs) are a family of innate immune system receptors that initiate signals in response to diverse pathogen-associated molecular patterns in the innate immune system [1,2]. Ten functional TLRs (TLR1 to TLR10) have been identified in humans. TLRs are expressed in various mammalian immune-related cells such as mast calls, macro-phages, monocytes, and dendritic cells [3,4]. Each TLR recognizes different microbial components as ligands. For example, TLR2 recognizes peptidoglycans (PGNs) in the cell wall of Gram-positive bacteria [5], and TLR3 recog-nizes poly(I:C) produced during virus replication [6]. On the binding of specific ligands, TLRs trigger a signaling cascade and result in cytokine production, which drives an inflamma-tory response and activates the adaptive immune system [7]. Age-related macular degeneration (AMD) is the leading cause of blindness in the elderly all over the world [8]. It is believed that inflammation plays an important role in AMD pathogenesis [9,10]. A mutation of the complement factor H gene, which is involved in a component of the immune system that regulates inf lammation, has been linked to AMD [11]. However, mechanisms initiating and perpetuating inflammation in AMD remain to be elucidated. Further inves-tigations concerning how the immune system dysfunction causes AMD will not only elucidate the underlying mecha-nisms but also lead to novel therapeutic strategies. Multiple genetic and environmental factors [12], such as innate immunity and oxidative stress, are associated with AMD. Human retinal pigment epithelium (RPE) cells play a principal role in immune defense. The RPE expresses TLR1–7 and 9–10, and its dysfunction is crucial for the clinical changes seen in AMD [13]. Treatment of RPE with poly(I:C) resulted in increased production of proinflammatory cyto-kines and chemokines [14]. Kleinman and colleagues found that activation of TLR3 by poly(I:C) induced RPE death,