Made available in DSpace on 2014-12-17T15:32:31Z (GMT). No. of bitstreams: 1 ManoelAGN_tese.pdf: 5283581 bytes, checksum: 65511a1dd2487deff44e8db44d2a0cf5 (MD5) Previous issue date: 2006-08-18 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The objective of this study was perform by the streptoavidin-biotin technique an immunohistochemical analysis of ?2?1, ?3?1e ?5?1 integrins in 11 normal oral mucosa (NOM), 16 oral inflammatory fibroepithelial hyperplasia (OIFH) and 25 oral epithelial dysplasia (OED) (16 mild, 2 moderates and 7 severe), to determine if exists qualitative alteration in the expression of these integrins and if this guard relation with the oral epithelial modifications. It was observed that for the ?2?1 integrin the majority of the sample showed a predominantly intense labeling diffusely distributed in the intercellular contacts and the cytoplasm of cells of the basal and suprabasal layers, without difference of this profile between the different types of specimens, however with a trend to weak or loss of expression in 21.1% of the OEDs, being all the specimens that had not expressed this heterodimer, severe OEDs. For the ?3?1 integrin the majority of the sample showed a weak or absent labeling in basal layer. The ?5?1 integrin showed a predominant strong diffuse labeling in the intercellular contacts and cytoplasm in the suprabasal layer, with difference only in the labeling intensity between the types of specimens, inhabiting this difference in the OEDs, where 12 (48%) specimens had shown a weak labeling. It was concluded that the evaluated integrins can be involved in the cell-cell, cell-ECM interactions modulating the cellular differentiation and maintenance of the epithelial structural arrangement. The variable expression of the ?5?1 integrin in the OEDs, could suggest, respectively, a role of this molecule in the cellular survival, with intention to perpetuate the modified phenotype in these lesions, or a suppressor role on the modified phenotype due to lack of interaction of this molecule with the fibronectina of the MEC / Este estudo se prop?s analisar atrav?s da t?cnica da estreptoavidina-biotina a express?o imuno-histoqu?mica das integrinas ?2?1, ?3?1e ?5?1 em 11 esp?cimes de mucosa oral normal (MON), 16 de hiperplasia fibroepitelial inflamat?ria oral (HFIO) e 25 de displasia epitelial oral (DEO) (16 leves, 2 moderadas e 7 graves), procurando determinar se existe altera??o qualitativa na express?o destas integrinas e se a mesma guarda rela??o com as modifica??es sofridas pelo epit?lio oral. Para a integrina ?2?1 a maioria dos esp?cimes exibiu uma marca??o predominantemente intensa e difusa nos contatos intercelulares e no citoplasma celular das camadas basal e suprabasal, sem diferen?a desse perfil entre os diferentes tipos de esp?cimes, por?m com uma tend?ncia a fraca ou perda da express?o em 21.1% das DEOs, sendo todos os esp?cimes que n?o expressaram marca??o para este heterod?mero DEOs graves. Para a integrina ?3?1 a maioria da amostra exibiu uma marca??o fraca ou ausente predominantemente em camada basal. A integrina ?5?1 exibiu uma forte marca??o difusa nos contatos intercelulares e citoplasm?tica na camada suprabasal, com diferen?a apenas na intensidade de marca??o entre os tipos de esp?cimes, residindo essa diferen?a nas DEOs, onde 12 (48%) esp?cimes exibiram uma fraca marca??o. Concluiu-se que as integrinas avaliadas podem estar envolvidas nas intera??es c?lula-c?lula e c?lula-MEC que garantem a diferencia??o celular e manuten??o do arranjo estrutural tecidual. A vari?vel express?o da integrina ?5?1 nas DEOs, poderia sugerir, respectivamente, um papel dessa mol?cula na sobrevida celular, com o intuito de perpetuar o fen?tipo alterado nessas les?es, ou uma a??o supressora desse fen?tipo devido ? falta de intera??o desta mol?cula com a fibronectina da MEC