Table 1.
Classification of the Identified Types of Toll-Like Receptors and Their Main Activators
| TLR | Main Ligands | Associated Pathogen |
|---|---|---|
| Location: plasma membrane | ||
| TLR1 | Triacylated Lipoproteins | Bacteria Mycobacteria |
| TLR2 | Lipoproteins Zymosan Mannan Others |
Bacteria Mycobacteria Fungi Protists Nematodes |
| TLR4 | Lipopolysaccharide Heat-shock proteins Oligosaccharides |
Bacteria Nematodes Viruses |
| TLR5 | Flagellin | Bacteria |
| TLR6 | Lipoproteins Zymosan |
Bacteria Fungi |
| TLR10 | Unknown | Unknown |
| Location: endosomes | ||
| TLR3 | dsRNA | Viruses |
| TLR7 | ssRNA Synthetic compounds |
Viruses |
| TLR8 | ssRNA Synthetic compounds |
Viruses |
| TLR9 | Unmethylated CpG oligos | Viruses Bacteria |
dsRNA = double-stranded RNA; ssRNA = single-stranded RNA; TLR = toll -like receptor.