Toll-Like Receptors (Tlr) 2 and 4 Expression of Keratinocytes From Patients With Localized and Disseminated Dermatophytosis

Abstract

There are few studies on the role of innate immune response in dermatophytosis. An investigation was conducted to define the involvement of Toll-Like Receptors (TLRs) 2 and 4 in localized (LD) and disseminated (DD) dermatophytosis due to T. rubrum. Fifteen newly diagnosed patients, eight patients with LD and seven with DD, defined by involvement of at least three body segments were used in this study. Controls comprised twenty skin samples from healthy individuals undergoing plastic surgery. TLR2 and TLR4 were quantified in skin lesions by immunohistochemistry. A reduced expression of TLR4 in the lower and upper epidermis of both LD and DD patients was found compared to controls; TLR2 expression was preserved in the upper and lower epidermis of all three groups. As TLR4 signaling induces the production of inflammatory cytokines and neutrophils recruitment, its reduced expression likely contributed to the lack of resolution of the infection and the consequent chronic nature of the dermatophytosis. As TLR2 expression acts to limit the inflammatory process and preserves the epidermal structure, its preserved expression may also contribute to the persistent infection and limited inflammation that are characteristic of dermatophytic infections.

Keratitis–ichthyosis–deafness syndrome accompanied by disseminated cutaneous fungal infection

“…The paraffin‐embedded tissues (right thigh, abdomen and forehead) were carried out for immunohistochemistry staining of TLR2 and TLR4 as described elsewhere . The normal prepuce tissues harvested from clinical circumcision surgery were embedded in the paraffin and processed at the same time as a normal human skin control.…”

“…The paraffin-embedded tissues (right thigh, abdomen and forehead) were carried out for immunohistochemistry staining of TLR2 and TLR4 as described elsewhere. 11 The normal prepuce tissues harvested from clinical circumcision surgery were embedded in the paraffin and processed at the same time as a normal human skin control. In addition, the anti-TLR2 antibody (NOVUS Biologicals, Littleton, CO, USA) was used in a 1:100 dilution, and anti-TLR4 antibody (NOVUS Biologicals) was used in a 1:500 dilution.…”

Management of tinea corporis, tinea cruris, and tinea pedis: A comprehensive review

“…A reduced expression of TLR-4 in the lower and upper epidermis of both localized and disseminated dermatophytosis patients was found compared to controls; TLR-2 expression was preserved in the upper and lower epidermis of all three groups. [ 18 19 ]…”

Perspective on animal models of dermatophytosis caused byTrichophyton rubrum

“…For example, the models have shown that IFN-g, IL-12, IL-1b, and IL-17 are important cytokines for controlling T. rubrum infection and that skin lesions of patients present lower expression of Toll-like receptor 4 (TLR4) than that seen in the control groups. 1,17,8 Furthermore, both dendritic cells (DCs) and macrophages interact with T. rubrum conidia, 8,9,18 but Santiago et al 18 demonstrated that only DCs inhibited T. rubrum growth and induced Th activation, suggesting that these cells play an important role in coordinating the development of the cellular immune response during T. rubrum infection. In conclusion, much work is still required to provide scientific information about dermatophyte infections to a level at least similar to that for other fungal infections caused by species that are easier to manipulate (e.g., Candida and Cryptococcus).…”