TLR3 (Toll-Like Receptor-3) acts as a major receptor in virus-mediated innate immune response. This protein belongs to TLR (Toll-like receptor) family which comprises of 10-12 type I integral membrane receptor paralogs that recognize pathogen associated molecular signatures and initiate inflammatory responses. TLR3 consist of pathogen-binding ECD (Ectodomains) and cytoplasmic signaling domains, known as TIR (Toll IL-1 Receptor) domains, joined by a single transmembrane helix. TLR3 specifically senses dsRNA (Double-stranded RNA), an almost universal viral intermediate generated during most viral replications. TLR-3 activation induces multiple cellular antiviral responses, including production of IFN-alpha/beta and up-regulation of the anti-HIV cellular factor APOBEC3G. These are a family of pattern recognition receptors expressed by immune cells, including macrophages.