REGULATORY T CELLS IN THE SKIN LESIONS AND BLOOD OF PATIENTS WITH SYSTEMIC SCLEROSIS AND MORPHEA.
Posted Feb 02 2010 12:00am
Systemic sclerosis (SSc) and morphea are connective tissue diseases characterized by fibrosis of the skin. Although to date their pathogenesis has not yet been clearly defined, it is thought that autoimmunity may play a role in the development of the skin lesions observed in both these diseases. As regulatory T cells (Treg) play a key role in the modulation of immune responses, it has recently been suggested that Treg impairment may lead to the development of autoimmune diseases.
To investigate the presence of Treg and their immunomodulatory cytokines transforming growth factor (TGF)-beta and interleukin (IL)-10 in patients with SSc and morphea.
Fifteen patients with SSc and 15 with morphea were enrolled. Immunohistochemistry was applied to identify forkhead/winged helix transcription factor (FoxP3)(+) Treg, TGF-beta(+) cells and IL-10(+) cells in the skin, cytofluorimetry to detect CD4(+)CD25(+)FoxP3(+) Treg in the blood and enzyme-linked-immunosorbent-assays to analyse TGF-beta and IL-10 serum levels.
Fewer FoxP3(+) Treg, TGF-beta(+) and IL-10(+) cells were found in the skin of scleroderma patients than in controls. Similarly, there were reduced TGF-beta and IL-10 serum levels and fewer circulating CD4(+)CD25(bright)FoxP3(+) cells both in SSc and morphea patients, than in controls.
The quantitative reduction of Treg, along with that of TGF-beta and IL-10 serum levels may well be responsible for the loss of tolerance observed in both SSc and morphea.