Made available in DSpace on 2014-12-17T15:32:18Z (GMT). No. of bitstreams: 1 JoabeSP.pdf: 1318134 bytes, checksum: 051d3ab3425024319d41e93c3e0af738 (MD5) Previous issue date: 2010-03-15 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / T regulatory cells have the function of controlling immune responses and maintaining self-tolerance. The FoxP3 has been considered the most specific marker for Treg cells. The aiming of this paper was to evaluate the immunoexpression of FoxP3 in the inflammatory infiltrate from oral lichen planus (OLP) and to compare it with the infiltrate in fibrous inflammatory hyperplasia (FIH) and then, between reticular and erosive forms of OLP. The samples were composed by 32 cases of OLP (17 reticular and 15 erosive) beyond 10 cases of FIH that were submitted to immunohistochemistry staining for FoxP3. Localization of the staining was classified in underepithelial and intraepithelial and the amount of FoxP3+ cells was evaluated through cells counting in 10 consecutive fields, at 400x power magnification. The values were expressed in mean ? standart deviation, and submitted to statistical tests with 5% of significance level. It was observed a statistical significant difference in the amount of FoxP3+ Treg cells between the two combined forms of OLP (1,6 ? 2,2) and the FIH (0,5 ?0,4) (P<0,05). This maybe could be explained by immunological mechanism of OLP, which involves a permanent antigenic induction likely with consequent perpetuation of lesion, eliciting the proliferation and constant recruitment of Treg cells. Otherwise, FIH presents a different etiopathogenesis, in which there is also generation of a variable inflammatory infiltrate, however qualitatively distinct from that seen in OLP. The erosive form of OLP exhibited a greater number (1,7 ? 2,4) of FoxP3+ Treg cells than reticular form (1,5 ? 2,1). These alterations could have relation with the great disease activity verified in erosive OLP, or also, with abnormalities in the regulatory function of Treg cells that could cause the increase observed. Considering the capacity already well established in the literature, both about Treg cells in modulating immune responses, as in the oral mucosa in showing great potential for regeneration, it is suggested that the possibility of development and implantation of immunotherapeutic strategies that regulate the frequency and function of these cells, may help in future treatment of immune-mediated inflammatory diseases such as OLP / As c?lulas T regulat?rias (Treg) possuem a fun??o de controlar respostas imunes e manter a autotoler?ncia. O FoxP3 tem sido considerado o marcador mais espec?fico para c?lulas Treg. O objetivo deste estudo foi avaliar a imunoexpress?o do FoxP3 no infiltrado inflamat?rio do l?quen plano oral (LPO) comparado ao da hiperplasia fibrosa inflamat?ria (HFI) e posteriormente entre as formas reticular e erosiva do LPO. A amostra foi composta por 32 casos de LPO (17 reticulares e 15 erosivos) al?m de 10 casos de HFI que foram submetidos ? marca??o imunoistoqu?mica para o FoxP3. A localiza??o da marca??o foi classificada em justaepitelial ou intraepitelial e a quantidade das c?lulas FoxP3+ foi avaliada atrav?s da contagem destas em 10 campos consecutivos, com aumento de 400x. Os valores foram expressos em m?dia ? desvio-padr?o, e submetidos aos testes estat?sticos com n?vel de signific?ncia de 5%. Observou-se uma diferen?a estatisticamente significativa na quantidade de c?lulas Treg FoxP3+ entre os dois tipos de LPO reunidos (1,6 ? 2,2) e a HFI (0,5 ? 0,4) (P<0,05). Isto talvez possa ser explicado pelo mecanismo imunol?gico do LPO, que envolve uma prov?vel indu??o antig?nica permanente com conseq?ente perpetua??o da les?o, suscitando a prolifera??o e recrutamento constante das c?lulas Treg. Em contrapartida, a HFI apresenta uma etiopatogenia diferente, na qual tamb?m h? gera??o de um infiltrado inflamat?rio vari?vel, por?m qualitativamente distinto do verificado no LPO. A forma erosiva do LPO exibiu um maior n?mero (1,7 ? 2,4) de c?lulas Treg FoxP3+ que a forma reticular (1,5 ? 2,1). Estas altera??es podem ter rela??o com a maior atividade da doen?a verificada no LPO erosivo, ou ainda, com anormalidades na fun??o reguladora das c?lulas Treg que ocasionariam o aumento observado. Considerando-se a capacidade j? bem estabelecida na literatura, tanto das c?lulas Treg modularem as respostas imunol?gicas, quanto da mucosa oral em exibir um grande potencial de regenera??o, sugere-se que a possibilidade de desenvolvimento e implanta??o de estrat?gias imunoterap?uticas que regulem a freq??ncia e a fun??o destas c?lulas, possa futuramente auxiliar no tratamento de doen?as inflamat?rias mediadas imunologicamente, como o LPO