Menezes, Cristiane Alves da SilvaSullivan, A. K.Falta, M. T.Mack, D. G.Freed, B. M.Rocha, Manoel Otávio da CostaGollob, Kenneth JohnFontenot, A. P.Dutra, Walderez Ornelas2017-06-052017-06-052012MENEZES, C. A. da S. et al. Highly conserved CDR3 region in circulating CD4(+) Vβ5(+) T cells may be associated with cytotoxic activity in Chagas disease. Clinical and Experimental Immunology, v. 169, p. 109-118, 2012. Disponível em: <http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2249.2012.04608.x/abstract>. Acesso em: 19 fev. 2017.1365-2249http://www.repositorio.ufop.br/handle/123456789/7880Human infection with Trypanosoma cruzi leads to Chagas disease, which presents as several different clinical conditions ranging from an asymptomatic form to a severe dilated cardiomyopathy. Several studies have demonstrated that T cells play a critical role in the development of cardiac pathology, as well as in immunoregulation during chronic disease. However, the mechanisms that drive protective or pathogenic T cell response are not known.We have shown that CD4+ T cells from chagasic patients preferentially express T cell receptor (TCR) b-chain variable region (Vb) 5. The aim of this work was to determine whether T cells expressing this particular Vb region displayed variable or restricted CDR3 sequences, as an indicator of the nature of the stimulus leading to the activation of these T cells in vivo. Additionally, we aimed to evaluate phenotypic characteristics of these cells that might be associated with pathology. CDR3 junctional region sequencing of Vb5·1 expressing CD4+ T cells revealed the occurrence of a highly homologous CDR3 region with conserved TCR Jb region usage among patients with cardiac, but not indeterminate, Chagas disease. Moreover, correlation analysis indicated that the frequency of CD4+Vb5·1+ cells is associated with granzyme A expression, suggesting that these cells might display cytotoxic function. Together these results provide new insight into T cell recognition of antigens involved in Chagas disease and suggest that these cells may be implicated in the pathogenesis of chagasic cardiomyopathy.en-USrestritoArtigo publicado em periodicohttp://onlinelibrary.wiley.com/doi/10.1111/j.1365-2249.2012.04608.x/abstracthttps://doi.org/10.1111/j.1365-2249.2012.04608.x