Expression of TLR9 and its mRNA in the lesions of lichen planus

Abstract

To investigate the role of toll-like receptor 9 (TLR9) in the pathogenesis of lichen planus, the expressions of TLR9 and its mRNA in the lesional skin of lichen planus were detected by immunohistochemical technique (SP) and RT-PCR. As control, normal skin of healthy volunteers was also tested. The immunohistochemical study showed that the expression of TLR9 in the lesional skin of lichen planus was significantly higher than that in the normal controls. The results of RT-PCR showed that both skin lesions and normal controls had TLR9 expression. In skin lesions, the expression level of TLR9 mRNA was 1.6075+/-0.0930, which was significantly higher than that in normal controls (P<0.001). These findings indicated that up-regulated expression of TLR9 and its mRNA might be involved in the pathogenesis of lichen planus.

Expression of toll-like receptor 9 and human herpes virus 7 in lichen planus

“…Our results were in agreement with an earlier study [3], which reported upregulation of TLR9 in LP lesions. Our results were in agreement with an earlier study [3], which reported upregulation of TLR9 in LP lesions.…”

“…In recent years, there has been growing interest in the role of innate immunity to explain the relation between environmental triggers and the exacerbation of autoimmune T cells leading to LP [3], with toll-like receptors (TLRs) being the link between innate and adaptive immunity [4]. TLRs have recently emerged as key sensors of invading microbes, acting through recognition of pathogen-associated molecular patterns [5].…”

TLR4 and TLR9 are induced in oral lichen planus

“…Oral mucosa is constantly in contact with microbes that could be recognized by TLRs, and the consequent inflammation cascade could possibly play a part in the pathogenesis of oral LP (OLP). Previous studies on the expression of TLRs in LP have shown that TLR9 expression is higher in the LP skin lesions than in healthy skin (22). Enhanced expression of TLR2 in mucosal lesions as well as peripheral blood monocytes of patients with OLP was recently reported by Ohno et al.…”

Downregulation of TLR‐7 receptor in hepatic and non‐hepatic patients with lichen planus

“…On the other hand, a recent study reported that TLR-9 mRNA was upregulated in LP, suggesting that it might play a role in the pathogenesis of the disease. 30 According to the results of this preliminary study, it seems that TLR-7 is downregulated in both HCV-positive and HCV-negative patients with LP. The reason for this downregulation may be a direct action of HCV or presence of decoy receptors in hepatic and non-hepatic patients, respectively.…”

“…On the other hand, a recent study reported that TLR‐9 mRNA was upregulated in LP, suggesting that it might play a role in the pathogenesis of the disease 30 …”