Matrix metalloproteinases (MMPs), such as collagenases, are a family of enzymes capable of degrading most constituents of the extracellular matrix. MMPs are thought to be involved in the aetiopathogenesis of tendon rupture. Additionally, failure of healing has in some instances been associated with elevated levels of MMPs. We have studied (a) the effects of the MMP-inhibitor doxycycline on healing of tendons and intestines in experimental models and (b) systemic levels of MMPs and their endogenous inhibitors (TIMPs) in patients with tendon rupture. In the first study, systemic doxycycline treatment lead to weakened rat Achilles tendons during healing after injury. Subsequently, systemic doxycycline was shown to improve biomechanical properties of tendon suture fixation in the rat Achilles tendon. Sutures were also coated with doxycycline, leading to similar improvement in mechanical strength of the suture construct during healing. In the third study, doxycycline-coated sutures improved the strength of healing intestinal anastomoses in an experimental model. Finally, we showed that patients with a history of Achilles tendon rupture had elevated levels of MMP-2, MMP-7 and TIMP-2 in serum. In addition, MMP-7 correlated inversely to mechanical strength of the tendon during healing. In conclusion, MMP-inhibitors can be administered systemically and locally to manipulate healing of tendons and intestines. Generalised alterations in the MMP-TIMP system may be involved in the pathogenesis of Achilles tendon rupture and associated with differences in outcome of healing.

No description available.

Diss. (sammanfattning) Linköping : Linköpings universitet, 2009. / Härtill 5 uppsatser.

Made available in DSpace on 2016-06-02T19:22:57Z (GMT). No. of bitstreams: 1 4992.pdf: 3011088 bytes, checksum: e16236b88f4430b4475a77ff532b2ae9 (MD5) Previous issue date: 2013-04-05 / Financiadora de Estudos e Projetos / The aim of the present study was to investigate the influence of resistance training on body composition and active matrix metalloproteinases 2 (MMP-2) on biceps and gastrocnemius muscles in rats with high fat diet. We evaluated 32 Wistar rats divided into four experimental groups (n=8/each) according to diet and exercise status: Control Group (C; standard diet), Obese Control Group [C-Ob; hiperlipidic diet (30% of fat)], Resistance Exercise (RE; standard diet) and Resistance Exercise Obese (RE-Ob; hiperlipidic diet). After weaning (day 21), animals were subjected to the experimental diet according to their groups during 24 weeks. A 12-week strength-training period was used, during which the animals climbed a 1.1-m vertical ladder with weights attached to their tails. The sessions were performed three times/week (Mondays, Wednesdays and Fridays, with 4 9 climbs/session and 8 12 dynamic movements/climb with two rest minutes. Resistance training induced a significant reduction in body mass, fat mass, fat percentage in group RE (p < 0,05). Resistance training increased the activity of MMP-2 on bicpes and gastrocnemius muscle (p < 0,05), favoring thus the tissue remodeling in both groups trained. Finally, the carrying load trained both groups was not statistically different, however, the relative strength (carrying load/body weight) was statistically higher in group RE (p < 0,05). Resistance training promoted significant changes in body composition, MMP-2 activity in the biceps and gastrocnemius and the relative strength. Thus resistance training may be a strategy to minimize the deleterious effects induced by consumption of a high fat diet and the co-morbidities associated with obesity in skeletal muscle. / O objetivo do presente estudo, foi investigar a influência do treinamento resistido na composição corporal e a atividade metaloproteinases de matrix 2 (MMP-2) nos músculos bíceps e gastrocnêmio em ratos alimentados com dieta hiperlipídica. Foram avaliados 32 ratos machos Wistar divididos em quarto grupos experimentais (n=8/cada) de acordo com o tipo de dieta e o treinamento: Controle (C; dieta padrão), Controle Obeso [C-Ob; dieta: hiperlipídica (30% de gordura)], Exercício Resistido (EX; dieta padrão) e Exercício Resistido Obeso (EX-Ob; dieta hiperlipídica). Após o desmame (dia 21), os animais foram submetidos à dieta experimental durante 24 semanas. Após 12 semanas de dieta os animais realizaram um período de 12 semanas de treinamento resistido, durante o qual os animais escalavam uma escada vertical de 1,1 metros com pesos atados a cauda. As sessões de treinamento foram realizadas três vezes por semana (segunda, quarta e sexta-feira) com 4 a 9 escaladas e 8 a 12 movimentos dinâmicos a cada subida com dois minutos de intervalo de recuperação. O treinamento resistido induziu redução significativa na massa corporal, massa gorda, percentual de gordura nos animais do grupo EX (p < 0,05). O grupo C apresentou massa corporal e massa gorda significativamente maiores e valores de massa magra significativamente menores quando comparado com os animais do grupo EX. O treinamento resistido aumentou a atividade da MMP-2 nos músculos bíceps e gastrocnêmio (p < 0.05), favorecendo dessa forma, o remodelamento tecidual em ambos os grupos treinados. Por fim, a carga de carregamento de ambos os grupos treinados não foi diferente estatisticamente, no entanto, a força relativa (carga de carregamento/massa corporal) foi estatisticamente maior no grupo EX (p<0.05). O treinamento resistido promoveu mudanças importantes na composição corporal, atividade da MMP-2 nos músculos bíceps e gastrocnêmio e na força relativa. Assim o treinamento resistido pode ser uma estratégia para minimizar os efeitos deletérios induzidos pelo consumo de uma dieta hiperlipídica e as co-morbidades associadas à obesidade no músculo esquelético

Orientador: Carlos Augusto Araújo Valadão / Banca: José Corrêa de Lacerda Neto / Banca: Rafael Resende Faleiros / Resumo: A laminite está associada a ativação inflamatória sistêmica, a qual ocorre em diversas afecções, principalmente as gastrointestinais. Sua patogenia este relacionada a ativação de metaloproteinases e degradação do colágeno e/ou hemidesmossomos. 0 objetivo deste estudo foi analisar alterações morfológicas, apoptose, metaloproteinases (MMP) 2 e 9 e infiltração leucocitária, pela pesquisa da lipocalina liberada por neutrófilos (NGAL), no tecido laminar de equinos submetidos a obstrução intestinal experimental. Os animais foram distribuídos nos grupos: controle (Gc), instrumentado (Gi), com procedimento de enterotomia sem obstrução; obstruído tratado com hidrocortisona (Gt) e obstruído não tratado (Gnt). 0 tecido laminar foi analisado pelas técnicas de microscopia em luz, imunohistoquímica e zimografia. Os animals dos grupos experimentais (Gi, Gt e Gnt) demonstraram alterações morfológicas, MMPs e substância formada pela M M P-9 e NGAL superiores aos resultados do Cc. A presença de apoptose não foi evidenciada pelo procedimento cirúrgico. 0 Gc não foi diferente quanto as alterações morfológicas quando comparado ao Gi, e também não diferiu do Gt em relação e MMP-9, principalmente associada a neutrófilos. Com estes resultados, conclui-se que: o modelo experimental pode causar alterações morfológicas associadas a laminite; a apoptose não participa da fase inicial de alterações laminares no córium laminar; a hidrocortisona pode ser utilizada para coibir os efeitos deletérios da ativação inflamatória associada a diversas doenças, sem comprometer o córium laminar. / Abstract: The laminitis is associated to systemic inflammatory activation that occur in several diseases, mainly gastrointestinal. The pathogeny of the laminitis is related to matrix metalloproteinases (MMPs) activation with collagen or hemidesmossomos degradation. The aim of this study is evaluated of the morphologic alterations, apoptosis, MMPs 2 and 9 and leukocyte infiltration, for research of MMP-9 related to neutrophil gelatinase associated to lipocalin (NGAL) in laminar corium of horses subjected to intestinal obstruction experimental. The animals were divided in groups: control (Cc), instrumented (Gi), with enterotomy without obstruction; obstruction treated by hydrocortisone (Gt) and without treatment (Gnt). The laminar tissue was analyzed by optical microscopy, immunohistochemistry and zymography. The animals showed morphologic alterations, MM Ps expression and MMP-9 associated to NGAL greater the Gc. The presence of apoptosis was not evidend by cirurgical procedure. However, the Gc was not different to Gi about morphologic alterations, and too Gt, about MMP-9, mainly the form conjugated to NGAL. The results indicate that the experimental model can cause morphologic alterations associated with laminitis. The apoptosis is not prerequisite for laminar lesion. The hydrocortisone can be administrated to reduce the deleterious effects of inflammatory activation in several diseases, without to affect the laminar corium. / Mestre

Made available in DSpace on 2014-12-17T15:32:15Z (GMT). No. of bitstreams: 1 BetaniaFR.pdf: 636142 bytes, checksum: 6061eebe55028f4725bba3031ee70b7a (MD5) Previous issue date: 2008-02-26 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Ameloblastoma and adenomatoid odontogenic tumor are odontogenic tumors arising from the odontogenic epithelium with distinct clinical behavior. In attempt to comprehend the interaction between the odontogenic tumor cells and the extracellular matrix, the present work evaluated and compared the immunohistochemical expression of the matrix metalloproteinases-1 (MMP-1), -2 (MMP-2) and -9 (MMP-9) in 20 cases of ameloblastoma and 10 adenomatoid odontogenic tumor. MMP-1 exhibited exuberant expression in the parenchyma and in the stroma of both studied tumors, while the MMP-2 showed varied expression with about of 80% and 60% of the neoplastic cells exhibiting positivity in the ameloblastoma and adenomatoid odontogenic tumor, respectively. With relation to the MMP-2 expression by the mesenchymal cells, it was observed that 65% of the ameloblastoma and 80% of the adenomatoid odontogenic tumor were positive. The immunoreactivity of MMP-9 was detected in all studied cases, although its expression had occurred predominantely in less than 50% of the parenchyma cells of the ameloblastoma, while in about of 60% of the adenomatoid odontogenic tumor more than 50% of cells were positive. The mesenchymal cells were positive to MMP-9 in 65% of the ameloblastoma and in 80% of the adenomatoid odontogenic tumor, respectively. Statistically significant difference was observed to the MMP-1 expression with relation to MMP-2 and MMP-9 in the ameloblastoma (p < 0.001). It was not possible to perform statistical analysis to the cases of adenomatoid odontogenic tumor, however there was a tendency toward a differential expression of the MMP-1 with relation to other studied MMPs. These results suggest that MMP-1, - 2 and -9 are implicated in the growth and progression of both tumors analyzed as well as the more pronounced participation of the stroma in the ameloblastoma could together to be related to the higher clinical aggressiveness / O ameloblastoma e o tumor odontog?nico adenomat?ide s?o tumores odontog?nicos derivados do epit?lio odontog?nico que possuem comportamentos distintos. Na tentativa de compreender a intera??o existente entre as c?lulas tumorais e a matriz extracelular, o presente trabalho teve como objetivo avaliar e comparar a express?o das metaloproteinases-1 (MMP-1), -2 (MMP-2) e -9 (MMP-9), atrav?s da t?cnica imuno-histoqu?mica em 20 casos de ameloblastoma e 10 de tumor odontog?nico adenomat?ide. A MMP-1 teve uma marca??o predominante nos dois tumores, sendo observada tanto no par?nquima como no estroma de todos os tumores estudados. Para a MMP-2, observou-se uma express?o variada, sendo 80% e 60% das c?lulas tumorais imunorreativas nos ameloblastomas e tumores odontog?nicos adenomat?ides, respectivamente. Em rela??o ?s c?lulas do mes?nquima, 65% dos ameloblastomas e 80% tumores odontog?nicos adenomat?ides exibiram positividade. Verificou-se imunoexpress?o para a MMP-9 nas c?lulas parenquimatosas e estromais em todos os casos, sendo que nos ameloblastomas, houve o predom?nio de menos de 50% das c?lulas imunomarcadas; enquanto que em 60% dos tumores odontog?nicos adenomat?ides mais de 50% das c?lulas apresentaram positividade. Observou-se diferen?a estatisticamente significante na express?o da MMP-1 em rela??o ? MMP-2 e -9 nos ameloblastomas (p<0,001). A an?lise estat?stica n?o p?de ser aplicada para os tumores odontog?nicos adenomat?ides, por?m verificou-se tend?ncia de maior express?o da MMP-1 em rela??o ?s outras MMPs avaliadas. Os resultados deste estudo sugerem que as MMPs-1, -2 e -9 est?o relacionadas com crescimento e progress?o dos tumores analisados e, particularmente no ameloblastoma, sua maior agressividade pode resultar, em parte, pela participa??o tamb?m do estroma presente de forma bem mais marcante permeando o par?nquima tumoral e sendo fonte tamb?m das proteases estudadas

Made available in DSpace on 2014-12-17T15:32:22Z (GMT). No. of bitstreams: 1 CassianoFWN.pdf: 2062817 bytes, checksum: d3cc1231e84c63282116f5950923db98 (MD5) Previous issue date: 2006-02-23 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The odontogenic myxoma shares cellular and structural aspects with dental papilla, which has been implicated as probable origin of this neoplasm. The aim of the present study was to perform a comparative immunohistochemical analysis for the expression of collagenase-1 (MMP-1) and gelatinases A (MMP-2) and B (MMP-9) in odontogenic myxomas and dental papilla of teeth germs. Twelve cases of odontogenic myxomas and eight specimens of teeth germs were selected. It was taken into consideration the presence or absence of immunoreactivity, the pattern of immunohistochemical distribution of proteases within extracellular matrix, as well as, the number of cells revealing immunostaining for matrix metalloproteinases (MMPs). It was verified a significant difference (p<0,05) in relation to MMP-2 immunoexpression, which was observed only within extracellular matrix of myxomas. Nevertheless, MMP-1 labeling was revealed by most of the cases of odontogenic myxoma, at levels close to those observed in dental papilla. In relation to the pattern of distribution, a significant difference was obtained between specimens (p<0,05), with neoplasms predominantly exhibiting a focal pattern for MMP-1. The quantitative analysis of neoplastic cells labeled for MMPs denoted a significant difference (p<0,05), demonstrating a higher proportion of MMP-1 in comparison to MMPs-2 and -9. It can be concluded that immunohistochemical expression of MMP-1 at levels comparable to those observed in dental papilla and quantitatively superior in relation to MMPs-2 and -9, suggest an implication of this protease on extracellular matrix degradation of odontogenic myxomas. Moreover, the possibility of interactions with receptors involved in cellular adhesion, particularly with integrins, suggests a plausible function on local invasiveness of such neoplasms. Additionally, the presence of a descent immunoexpression gradient for these MMPs on odontogenic myxomas, associated to substrate specificity inherent in each enzyme, suggest the existence of a coordinated mechanism between interstitial collagenase and gelatinases A and B in order to allow an efficient degradation of extracellular matrix and local invasion by neoplastic cells / O mixoma odontog?nico compartilha aspectos celulares e estruturais com a papila dent?ria, tendo-se implicado esta ?ltima como prov?vel origem deste neoplasma. O prop?sito desta pesquisa consistiu em analisar comparativamente a express?o imuno-histoqu?mica de colagenase-1 (MMP-1) e gelatinases A (MMP-2) e B (MMP-9) em mixomas odontog?nicos e papilas de germes dent?rios. Foram selecionados 12 casos de mixoma odontog?nico e 08 esp?cimes de germes dent?rios, para an?lise da presen?a ou aus?ncia de express?o imunohistoqu?mica e padr?o de distribui??o destas proteases em meio ? matriz extracelular, bem como, o n?mero de c?lulas positivamente marcadas para estas metaloproteinases de matriz (MMPs). Constatou-se diferen?a significativa (p<0,05) em rela??o ? imunorreatividade para MMP-2, apresentando-se expressa apenas em meio ? matriz extracelular dos mixomas. Para MMP-1 foi verificada imunorreatividade na maioria dos casos de mixomas, com propor??es semelhantes ?s constatadas nas papilas dent?rias. Em rela??o ao padr?o de distribui??o, evidenciou-se diferen?a significativa apenas para MMP-1 (p<0,05), com predomin?ncia do padr?o focal nos neoplasmas. Por sua vez, a quantidade de c?lulas imunorreativas ?s proteases, nos mixomas odontog?nicos, revelou diferen?as significativas (p<0,05), estando a MMP-1 presente em maiores propor??es, em compara??o com as MMPs-2 e -9. Concluiu-se que a express?o de MMP-1, em n?vel compar?vel ao constatado nas papilas de germes dent?rios e numericamente superior ?s MMPs-2 e -9, sugere a implica??o desta protease no processo de degrada??o da matriz extracelular nos mixomas odontog?nicos e, em decorr?ncia da possibilidade de associa??o das MMPs a receptores envolvidos no processo de ades?o celular, especialmente ?s integrinas, ainda um prov?vel papel na invasividade local destes neoplasmas. Adicionalmente, a evidencia??o de um gradiente descendente na express?o imuno-histoqu?mica das MMPs nos mixomas odontog?nicos, associada ? especificidade de substrato inerente a cada uma destas proteases, sugerem a exist?ncia de um mecanismo coordenado entre colagenase intersticial e gelatinases A e B, direcionado ? degrada??o eficiente da matriz extracelular e invas?o local por parte das c?lulas neopl?sicas

Made available in DSpace on 2014-12-17T15:32:24Z (GMT). No. of bitstreams: 1 LuizERJ_DISSERT.pdf: 1737074 bytes, checksum: 8941b0b8844e6080e5a540ee05d65531 (MD5) Previous issue date: 2014-02-28 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Ameloblastomas and keratocystic odontogenic tumors (KOT) represent odontogenic lesions that, despite their benign nature, are distinguished by a distinct biological behavior, characterized by locally aggressive growth and recurrent episodes. The gnathic bone resorption caused by the growth of these lesions is a key to the expansion of the same, both being mediated by osteoclastic cells like enzymatic activity of various matrix metalloproteinases (MMPs) factor. The expression of stimulatory factors and inhibitors of bone resorption has been correlated with the development of these lesions, with emphasis to some MMPs such as collagenases and gelatinases and tissue inhibitors of metalloproteinases (TIMPs), among others. Based on the premise that stimulatory and inhibitory factors of osteolytic processes can be decisive for the growth rate of intraosseous odontogenic lesions, this experiment evaluated the immunoreactivity of MMP-9, -13 and TIMP-1 protein in the epithelium and mesenchyme of ameloblastoma and the KOT specimens, by a quantitative analysis of the immunoreactivity cells. Statistical analysis was performed using the Mann-Whitney and Wilcoxon tests with a significance level set at 5 %. Immunohistochemical expression of MMP-9, -13 and TIMP-1 was observed in 100% of cases both in the epithelium and in mesenchyme. The immunoreactivity in the epithelium of KOT and ameloblastomas revealed a predominance of score 3 for MMP-9 (p=0.382) and MMP-13 (p=0.069) and no statistically significance for TIMP-1, the latter being significantly higher immunoreactivity in ameloblastomas. In the mesenchyme, there was a higher score immunoreactivity of MMP-13 (p=0.031) in ameloblastomas in relation to KOT, whereas for MMP-9 and TIMP-1 no statistically significant difference (p=0.403 was observed, p=1.000). The calculation of the ratio of scores revealed expression of proteins in general, similarity of the lesions, a significant predominance of equal expression of TIMP-1 and MMP-9 was observed only in the epithelium of ameloblastoma. The marked immunostaining of MMP-9 , MMP-13 and TIMP-1 in epithelium and mesenchyme of the lesion indicate that these proteins involved in ECM remodeling required for tumor progression, however, specific differences in the expression of some of these proteins, are not sufficient to suggest differences in the biological behavior of ameloblastomas and KOTs / Os ameloblastomas e tumores odontog?nicos ceratoc?sticos (TOC) representam les?es odontog?nicas que, apesar de sua natureza benigna, se destacam por um comportamento biol?gico distinto, caracterizado pelo crescimento localmente agressivo e epis?dios recidivantes. A reabsor??o dos ossos gn?ticos provocada pelo crescimento dessas les?es constitui um fator determinante ? expans?o das mesmas, sendo mediada tanto por c?lulas osteocl?sticas como pela a??o enzim?tica de diversas metaloproteinases de matriz (MMPs). A express?o de fatores estimuladores e inibidores da reabsor??o ?ssea vem sendo correlacionada com o desenvolvimento destas les?es, merecendo destaque algumas MMPs como as colagenases e as gelatinases e os inibidores teciduais de metaloproteinases (TIMPs), dentre outros. Baseados na premissa de que fatores estimuladores e inibidores de processos osteol?ticos podem ser determinantes para o ritmo de crescimento de les?es odontog?nicas intra?sseas, o objetivo de estudo foi avaliar a imunoexpress?o das prote?nas MMP-9, -13 e TIMP-1 no epit?lio e mes?nquima de esp?cimes de ameloblastomas e TOC. A an?lise estat?stica foi realizada atrav?s dos testes de Mann-Whitney e Wilcoxon com n?vel de signific?ncia estabelecido em 5%. Atrav?s de uma an?lise quantitativa das c?lulas imunomarcadas, foi observada a express?o imuno-histoqu?mica das MMP-9, -13 e TIMP-1 em 100% dos casos, tanto no epit?lio quanto no mes?nquima tumoral. Mais de 76% das c?lulas epiteliais (escore 3) dos TOC e ameloblastomas apresentaram imunomarca??o para MMP-9 (p=0,382) e MMP-13 (p=0,069), sendo estatisticamente significativa para o TIMP-1 (p=0,003) nos ameloblastomas. No mes?nquima, observou-se maior escore de imunomarca??o da MMP-13 (p=0,031) nos ameloblastomas em rela??o aos TOC, enquanto para a MMP-9 e TIMP-1 n?o se observou diferen?a estatisticamente significativa (p=0,403; p=1,000). O c?lculo da raz?o entre os escores de express?o das prote?nas revelou, de uma maneira geral, similaridade entre as les?es, sendo observado predom?nio significante de igualdade de express?o do TIMP-1 e da MMP-9 apenas no epit?lio dos ameloblastomas. A imunoexpress?o marcante das MMP-9, MMP-13 e TIMP-1 no epit?lio e mes?nquima das les?es estudadas indica que estas prote?nas participam na remodela??o da MEC necess?ria ? progress?o tumoral, no entanto, as diferen?as pontuais observadas na express?o de algumas destas prote?nas, n?o s?o suficientes para sugerir diferen?as no comportamento biol?gico dos ameloblastomas e dos TOCs

The aim of this work was to investigate the contribution of matrix metalloproteinases (MMPs) to recurrent corneal melting. Twenty three melted corneas from seven patients were separated into three groups: a) patients with primary Sjögren's syndrome, b) those with rheumatoid arthritis and c) those with other corneal melting underlying pathologies. Eleven cadaverous corneas served as controls. The presence of MMP-1, -2, -3, -7, -8, -9, and -13 was detected using indirect enzyme immunohistochemistry. The active forms of MMP-2 and -9 and MMP- 3 and -7 were examined by gelatin and casein zymography, respectively. The concentrations of active MMP-1 and -3 were measured using activity assays. Increased immunostaining intensity for MMP-1, -2, -3, -7, -8 and -9 was shown in the corneal epithelium and the stroma of almost all melted corneas from all three groups compared to the negative or slightly positive staining of the controls. In the endothelium, immunostaining for MMP-2 and MMP-9 was increased in most specimens of groups II and III and group I, respectively. A markedly higher level of active MMP-2 was detected in six, and active MMP-9 in all, pathologic specimens compared to the controls. In contrast to the completely negative controls, the proenzymes of MMP-3 and -7 were detected in almost all melted...

Os avanços relacionados à ciência dos biomateriais e engenharia tecidual buscam esclarecer os mecanismos envolvidos na resposta biológica associada ao uso desses dispositivos e sua interação com o sistema imune. Neste estudo, avaliou-se a resposta imune e inflamatória desenvolvida em camundongos frente à implantação de membrana de cortical óssea bovina no tecido subcutâneo, em implantação única e sequencial de duas membranas, assim como os possíveis mecanismos envolvidos no processo de reconhecimento e reabsorção desse biomaterial, de acordo com análise histomorfométrica, enzimática e molecular. Após a implantação da membrana, sinais de reabsorção que antes eram notados em pontos isolados, aos poucos se unem até sua completa degradação, observada somente após 15 dias. Todo o processo de reabsorção da membrana é acompanhado por uma reação inflamatória de magnitude moderada, seguida pelo declínio do número de leucócitos, surgimento de células gigantes multinucleadas e formação de uma cápsula de tecido conjuntivo fibroso. A cinética de TNF- e MMP-2, MMP-8, MMP-9 e MMP-13 apresentou um padrão de produção decrescente, entretanto os níveis dos inibidores de metaloproteinases (TIMPs) e TGF- parecem atuar de forma inversa. A velocidade de reabsorção após duas implantações consecutivas da membrana foi maior quando comparada ao grupo de animais que sofreu apenas uma implantação, porém os resultados do teste de hipersensibilidade do tipo tardia (DTH) demonstraram que a membrana é biocompatível, pois não elicitou resposta imunológica exacerbada após uma segunda implantação, confirmando então a natureza não imunogênica desse biomaterial. Finalmente, os animais CD14KO e MyD88KO apresentaram uma reabsorção mais lenta da membrana implantada, quando comparados aos animais C57Bl/6 (WT), demonstrando que as moléculas CD14 e MyD88 estão envolvidas no reconhecimento do biomaterial e desempenham importante papel no processo de reabsorção da membrana de cortical óssea bovina, indicando a participação de PAMPs e/ou DAMPs na resposta biológica gerada por esse biomaterial. / Advances related to the biomaterials science and tissue engineering seek to clarify the mechanisms involved in the biological response associated with the use of those devices and their interaction with the immune system. This study evaluated the inflammatory and immune response developed in mice after implantation bovine bone cortical membrane in subcutaneous tissue, in both, unique and sequential implantation of 2 membranes, as the mechanisms involved in this biomaterial recognition and resorption process, on regards to histomorphometric, enzymatic and molecular analysis. After membrane implantation, previously observed signs of resorption in isolated spots, gradually unite until their complete degradation after 15 days. The whole membrane resorption process is accompanied by a moderate inflammatory reaction, followed by a decline in the leukocytes number, appearance of multinucleated giant cells and formation of a capsule of fibrous connective tissue. The kinetics of TNF-, MMP-2, MMP-8, MMP-9 e MMP-13 showed a pattern of decreasing production, however, levels of metalloproteinases inhibitors (TIMPs) and TGF- seem to act in reverse way. The resorption rate after two successive membrane implantations was higher when compared to the group which suffered only one implantation, however, the results of delayed test hypersensity (DTH) demonstrated that the membrane is biocompatible, that is, it does not elicited too high immune response after a second position, confirming the non immunogenic nature of this biomaterial. Eventually, CD14KO and MyD88KO strains showed a slower membrane resorption when compared to animals C57Bl/6, demonstrating that the CD14 and MyD88 molecules are involved in biomaterial recognition and play an important role in bovine cortical bone membrane resorption process, indicating that PAMPs and/or DAMPs are involved in biological response generated by this biomaterial.