The Toll-like receptor (TLR) family in mammalian comprises a family of transmembrane proteins characterized by multiple copies of leucine rich repeats in the extracellular domain and IL-1 receptor motif in the cytoplasmic domain. Up-to-date, ten TLRs (TLR1-10) have been described.TLR8 gene contains three exons, two of which have coding function. Expression of TLR receptors is highest in peripheral blood leukocytes, macrophages, and monocytes.