01518nas a2200217   4500000000100000008004100001100001900042700001700061700001400078700001600092700001500108700001500123700002000138700001700158700001400175700001900189700001400208245005500222520100900277022001401286       2014                            d1 aQuaresma J A S1 aAarão T L S1 aSousa J R1 aBotelho B S1 aBarros L F1 aAraujo R S1 aRodrigues J L P1 aPrudente D L1 aPinto D S1 aCarneiro F R O1 aFuzii H T00aTh17 cytokines expression in leprosy skin lesions.3 a<p>Until recently, it was believed that Th1 and Th2 lymphocytes are the only effector cells of the immune response; however, another group of T cells producing cytokines that differ from those observed in the Th1-Th2 model has been identified recently. These cells comprise a third subtype of CD4+ effector T helper called type 17 T helper cells, or Th17(1) . Th17 lymphocytes produce IL-17, IL-17F, IL-6, IL-21, IL-22, and TNF-α, which play a role in both tissue inflammation and neutrophil activation(2) . IL-17 is a potent proinflammatory cytokine that exerts effects on a variety of cells(2) . In leprosy, the cytokine profile of the tuberculoid and lepromatous forms (stable forms) has been extensively investigated and is characterized by a Th1 and Th2 response, respectively(3) . However, the dimorphic forms are highly unstable and complex and Th17 lymphocytes may play an important role in the immunopathology of these lesions. This article is protected by copyright. All rights reserved.</p>
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