CD4+CD25+ Treg cells in patients with toenail onychomycosis

Abstract

The essential role played by CD25+CD4+ regulatory T (Treg) cells in the control of immunity against some pathogens such as Helicobacter pylori is now well established. But their role in cutaneous fungal infections is still unknown. Onychomycosis is the chronic fungal infection of the nails, which is very common. The aim of this study was to evaluate possible relationship of CD4+CD25+ Treg cells and onychomycosis. Peripheral blood samples were investigated for CD4+CD25+ Treg cells using flow cytometry analysis in 43 toenail onychomycosis patients and in 30 healthy controls. We have found that onychomycosis patients had a higher expression of CD25+CD4+ Treg cells than controls, with values of 8.45 +/- 4.47% versus 4.64 +/- 1.59%, respectively (P = 0.001). The results of this study suggests that increased numbers of CD4+CD25+ Treg cells may play a role in failure of clearance of dermatophytes from skin by preventing the protective inflammation which is leading to development of onychomycosis. Accordingly, we address the possibility that CD4+CD25+ Treg cells may play a role in immune pathogenesis of other superficial fungal infections.

Evaluation of improvement of onychomycosis in HIV‐infected patients after initiation of combined antiretroviral therapy without antifungal treatment

“…compared the expression of CD4 + CD25 + Treg cells in 43 HIV‐negative patients with toenail onychomycosis vs. 30 healthy controls. They found a higher expression of this T‐cell subpopulation in patients with onychomycosis, hence concluding that an increased number of Treg cells could originate an incapacity for clearing the dermatophyte infection by preventing the protective role of inflammation that leads to the infection development …”

“…They found a higher expression of this T-cell subpopulation in patients with onychomycosis, hence concluding that an increased number of Treg cells could originate an incapacity for clearing the dermatophyte infection by preventing the protective role of inflammation that leads to the infection development. 36 Also, in the HIV infection setting, the Treg (CD4 + CD25 + ) are proportionally increased among other CD4T cell subtypes as a result of the enhanced thymus production, survival rate and/or further conversion after contact with dendritic cells. 35,[37][38][39] Furthermore, some studies complement these results noting a positive correlation with viral load.…”

What′s new in nail disorders?

“…Development of newer techniques like polymerase chain reaction (PCR), [39] OCT, [26] flow cytometry, [40,41] and immunohistochemistry [42] for the diagnosis of OM is underway. The routine use is impractical at present because of some limitations.…”

Do Genetic Mutations and Genotypes Contribute to Onychomycosis?

“…There is an association between elevated levels of CD4+CD25+ regulatory T cells (Tregs) and onychomycosis [31]. In a study of 43 onychomycosis patients and 30 healthy controls, the level of CD4+CD25+ Tregs in the peripheral circulation was doubled in individuals with onychomycosis.…”