Regulatory T cells (Treg) are responsible for enforcing limits on the cell-mediated immune response and exert this function through immunosuppressive cytokines such as IL-10 and transforming growth factor (TGF)-β. The T lymphocytes CD4+ and CD8+ cells are capable of producing cytokines in line with Th1 or Th2. Stimulation by IL-12, LY2157299 mouse released by activated dendritic cells, induces differentiation in the direction of cytokine production,

Th1 and Th2 and suppression of Th17. IL-4 induces Th2 differentiation. CD4+ and CD8+, which release Th2 cytokines, have a regulatory role, because high concentrations of Th2 Vismodegib mw cytokines can suppress the actions of Th1 and Th17. Th17 cells are a subset of T helper cells producing IL-17; they are considered developmentally distinct from Th1 and Th2 cells, and excessive amounts of the cell are thought to play a key role in autoimmune disease. On initial characterization, Th17 cells have been broadly implicated in autoimmune disease, and autospecific Th17 cells have been shown to be highly pathological. A more natural role for Th17 cells is suggested by studies that have demonstrated preferential induction of IL-17 in cases of host

infection with various bacterial and fungal species. Th17 cells primarily produce two main members of the IL-17 family, IL-17A and IL-17F, which are involved in the recruitment, activation and migration of neutrophils; these cells also secrete IL-21 and IL-22 [11]. The pathogenesis of TAO is poorly understood; most hypotheses are controversial and the above-mentioned modern immunology concepts have not yet been applied to TAO patients. Therefore, this investigation Glutamate dehydrogenase was carried out to evaluate some components of the levels

of selected cytokines in the plasma of patients with TAO (smokers or former smokers). Informed consent was obtained from all the patients, and the study protocol was approved by the Ethics Committee of the University Hospital, Ribeirão Preto Faculty of Medicine, University of São Paulo, Brazil (no. 12810/2008). The study included 20 TAO patients (n = 10 female, n = 10 male) aged 38–59 years under clinical follow-up. The TAO diagnosis was based on the Shionoya and Olin criteria that are used routinely in our vascular division [9]. The five classic Shionoya criteria include a history of tobacco abuse, the onset of symptoms before the age of 50 years, infrapopliteal arterial occlusive disease, either upper limb involvement or phlebitis migrans and a lack of atherosclerotic risk factors other than smoking [9].