Transforming growth factor-β (TGF-β) superfamily of cytokines comprises of several members, which can broadly be sub-divided into three classes [TGF-βs, Activin/Nodal, and Bone morphogenetic proteins (BMPs)]. Most members of this family play critical roles during embryo development differentiation and regulation of homeostasis. In mammals there are three TGF-β isoforms, TGF-β1, 2 and 3. All the three TGF-β isoforms have important roles in embryo development as revealed by mouse knock-out models. TGF-β has also been associated with several pathological conditions such as inflammation, Fibrosis, and cancer. In cancers, TGF-β plays both tumor suppressive and tumor promoting roles depending upon the context. TGF-β has growth inhibitory effect on epithelial cells which is essential to maintain tissue homeostasis. TGF-β induces the expression of several cyclin dependent kinase inhibitors such as p21Cip1, p15Ink4b while down-regulating the expression of cMYC in the epithelial cells. In lieu of its tumor suppressive role, several cancers harbor mutations in the components of the TGF-β signaling axis such as receptors and effector molecules called SMADs. Interestingly various cancers also show hyper activation of TGF-β signaling. It has been suggested that cancer cells become unresponsive to the growth inhibitory effects of TGF-β by losing the expression of p21Cip1, and p15INK4b. Oncogenic transformation of cancer cells can override the growth inhibitory effects of TGF-β. While the loss of growth inhibitory effects by TGF-β are seen in the tumor cells, several tumor promoting actions are also observed in these cells such as induction of EMT. TGF-β activates mesenchymal cells leading to the formation of a reactive stroma in tumors and TGF-β suppresses almost all types of cells of the immune system causing a local immune-suppressive environment. TGF-β also recruits mesenchymal stem cells into the stroma which secrete several cytokines. The sum total of all these effects is pro-angiogenic, pro-infiltrative and pro-metastatic. In the canonical TGF-β signaling pathway, ligands bind to the hetero-tetrameric receptor complex of TGFβR1 and TGFβR2 leading to activation of the TGFβR1 by TGFβR2. Activated TGFβR1 then phosphorylates and activates R-SMAD molecules (SMAD2, SMAD3) which complexes with the co-SMAD (SMAD4) and translocate into the nucleus to effect transcriptional changes. Non-canonical TGF-β signals are many and almost all the known signaling pathways like MAPK, WNT, PI3K-AKT, NOTCH, Integrin, Hedgehog, Hippo etc. have been shown to be activated by TGF-β in different contexts. The canonical TGF-β/SMAD pathway has been shown to be essential for both tumor suppressive and tumor promoting actions of TGF-β. Although the non-canonical signalling pathways have been shown to be context dependent, the exact mechanisms have not been elucidated. In previous studies, we have shown the importance of non-canonical TGF-β signaling in normal vs. carcinoma cells. However, there has been no study that addressed the differential effects of TGF-β on cells of connective tissue origin. To throw light on such questions we have undertaken this study with the following objectives: 1) Whole genome expression profiling of TGF-β targets in normal fibroblasts, transformed fibroblasts and sarcoma cells 2) Elucidation of non-canonical signaling pathways differentially regulated by TGF-β 3) Identification and characterization of novel TGF-β targets The cell-lines chosen for the study are: 1) hFhTERT (human foreskin fibroblasts immortalized with human terminal telomerase); 2) hFhTERT-LTgRAS (hFhTERT transformed with SV40 large T antigen and activated RAS); and 3) HT1080 (fibrosarcoma). We performed whole genome expression profiling using 4×44K Agilent Human Whole Genome Oligonucleotide Arrays. Analysis of the microarray results revealed that TGF-β regulated a large number of genes in all the three cell-lines but few targets were found to be commonly regulated between any two or all the three cell-lines. 5291 genes were differentially regulated by TGF-β between hFhTERT and hFhTERT-LTgRAS and 2274 genes were differentially regulated by TGF-β between hFhTERT and HT1080 cells. Gene set enrichment analysis (GSEA) of these two gene lists revealed enrichment of similar gene sets in the HT1080 and hFhTERT-LTgRAS cells compared to the hFhTERT cells. MAPK signaling pathway components were enriched in the hFhTERT cells. Closer inspection revealed that several upstream regulators of the MAPK pathway were in fact down-regulated by TGF-β in these cells compared to both hFhTERT-LTgRAS and HT1080 cells suggesting a depression of the MAPK pathway by TGF-β in the hFhTERT cells. Assessment of the phosphorylation status of ERK1/2 and p38 MAPK proteins after TGF-β treatment showed that both ERK1/2 and p38 MAPK pathways were not activated in response to TGF-β in the hFhTERT cells. On the other hand in hFhTERT-LTgRAS and HT1080 cells, both ERK1/2 and p38 MAPK were activated post TGF-β treatment. Activity of the AP1 and SMAD responsive p3TP-lux reporter plasmid was dependent on only the SMAD pathway in hFhTERT cells while in the hFhTERT-LTgRAS and HT1080 cells both MAPK and SMAD pathway were found to regulate the expression of the p3TP-lux reporter. This suggests activation of MAPK and SMAD pathways in transformed and tumor cells while there is no activation of MAPK in normal cells of mesenchymal origin. Components of the WNT signaling pathway such as WNT ligands WNT4, and WNT11, frizzled receptors, FZD4, FZD8 and FZD9, regulators like SFRP1, SFRP2, AXIN2 and several targets of the WNT-β-catenin pathway were regulated by TGF-β in the hFhTERT cells but not in the hFhTERT-LTgRAS and HT1080 cells suggesting a positive regulation of the pathway by TGF-β in the hFhTERT cells. Indeed, TGF-β induced the activity of the WNT responsive reporter, pTOP-FLASH in the hFhTERT cells but not in the hFhTERTLTgRAS and HT1080 cells. WNT4 and WNT11 were two of the novel targets of TGF-β identified in hFhTERT cells. Further experiments suggested that TGF-β conferred regulation of these genes was specific to the fibroblast cells since induction of these genes by TGF-β was not observed in any of the cancer cell lines or in HaCaT cells. Some recent studies have demonstrated remodelling of cytoskeleton in epithelial cells by the non-canonical WNT ligands such as WNT5a, WNT4 and WNT11. WNT4 has also been shown to be required for the maintenance of α-SMA levels in smooth muscle cells. In this study we have shown that WNT4 can induce α-SMA in the hFhTERT cells leading to their activation. TGF-β conferred activation of these cells was also found to be dependent on the presence of WNT4. In brief, our study identified differentially activated pathways by TGF-β in immortal and transformed fibroblasts. WNT4 was identified as a crucial molecule required for the TGF-β conferred activation of fibroblasts.

published_or_final_version / Medicine / Master / Master of Philosophy

published_or_final_version / Obstetrics and Gynaecology / Master / Master of Philosophy

Cancer cell invasion and metastasis are hallmarks of cancer. It is becoming apparent that the interaction between cancer cells and the surrounding microenvironment are involved in their ability to invade and metastasise. In general, cancer cells can either migrate individually, in an amoeboid or mesenchymal manner, or collectively. The first aim of this thesis was to analyse the role of NG2 in amoeboid to mesenchymal transition (AMT) and Rho/ROCK signalling. We found that NG2 promotes an amoeboid morphology, and increased invasiveness, in a Rho-dependent manner. Secondly, we analysed the role of the major tumour microenvironment (TME) component, cancer-associated fibroblasts (CAFs), on melanoma cell invasiveness. We found the CAF interaction with melanoma cells leads to increased levels of interleukin-6 (IL-6) and IL-8, and this leads to increased invasiveness. Simultaneous blocking of IL-6 and IL-8, using neutralising antibodies, inhibits CAF-dependent invasion. Further analysis of another major component in the melanoma TME, keratinocytes, has highlighted the importance of the tumour cell niche in invasion. Our results indicate that cancer cells have the ability to change morphology, and that the TME plays an important role in melanoma cell invasiveness. Metastatic melanoma treatment has proven...

O ligamento periodontal e o tecido gengival são formados por tecido conjuntivo frouxo, sendo constituídos por diversas células, dentre as quais os fibroblastos são as mais numerosas. Ao serem submetidas a agressões diversas, estas células respondem com a liberação de substâncias, tais como citocinas e quimiocinas, que participam de maneira ativa no processo inflamatório, e com a produção de componentes da matriz extracelular fundamentais para o reparo, como por exemplo, o colágeno. Assim sendo, este trabalho teve como objetivo: Avaliar e comparar a expressão e a produção de prócolágeno tipo I, IL6, MIP1 e SDF1 por fibroblastos humanos, cultivados de ligamento periodontal e de tecido gengival, estimulados por lipopolissacarídeo (LPS) de Porphyromonas gingivalis. Foram coletados ligamentos periodontais de terceiros molares não irrompidos e biópsias de gengiva de um mesmo indivíduo (n=3). Estes tecidos foram picotados e mantidos em meio de cultura adequado para fibroblastos, que foram utilizados na quarta passagem. Após adesão dos fibroblastos a placas de 24 poços, o meio de cultura contendo 0,1 10 g/mL de LPS de P. gingivalis foi adicionado às placas em duplicata. O sobrenadante e as células foram coletados após 1, 6 e 24 horas e analisados por ELISA e PCR em tempo real, respectivamente. A análise estatística foi realizada por meio do programa GraphPad Prism, aplicandose o teste ANOVA a 1 critério com nível de significância de 5%. A expressão de prócolágeno tipo I mostrouse - ligeiramente diferente entre fibroblastos de ligamento periodontal e de gengiva. A produção de IL6, MIP1 e SDF1 foi significativamente maior em fibroblastos gengivais. A citocina IL6 foi produzida de maneira tempodependente com LPS de P gingivalis, principalmente por fibroblastos gengivais. Para MIP1, os fibroblastos gengivais mostraram maior produção com a menor concentração de estímulo (0,1g/ml). Para SDF1, foi detectada produção constitutiva que foi inibida com o aumento da concentração de LPS ao longo do tempo nestas mesmas células. Já para fibroblastos de ligamento periodontal, não foi observado um padrão homogêneo e linear, apesar de a produção basal de SDF1 também existir, porém em níveis bem mais discretos, como aquele observado para a produção de MIP1. A capacidade dos fibroblastos modificarem o padrão de produção dessas citocinas frente ao estímulo com LPS de P. gingivalis reforça a importância dessas células no contexto da resposta imune do indivíduo frente à doença periodontal. / The fibroblast is considered an important cell in periodontitis because it is the predominant cell type in the periodontal connective tissue. When challenged by different agents, fibroblasts respond through the release of substances, such as cytokines and chemokines that participate in an active way in the inflammatory process as well as the production of basic components of the extracellular matrix for repair, like collagen. The aim of this study was to: to evaluate and to compare the expression and production of type I procollagen, IL6, MIP1 and SDF1 by cultured human periodontal ligament and gingival fibroblasts challenged with lipopolyssacharide from Porphyromonas gingivalis. Human periodontal ligament and gingival fibroblasts were cultured from biopsies of the same donor and were used on the fourth passage. After confluence in 24well plates, the culture medium alone (control) or with 0,1 10 ug/mL of LPS from P. gingivalis were added and after 1, 6 and 24 hours, the supernatant and the cells were collected and analysed by ELISA and Real time PCR, respectively. Data were analysed by GraphPad Prism Program (1 way ANOVA test) and a significance level of 5% was adopted. Procollagen type I expression by Real Time PCR differ between periodontal ligament and gingival fibroblasts. In vitro experiments revealed that IL6, MIP 1 and SDF1 production were significantly greater in gingival fibroblasts when compared to periodontal ligament. In addition, IL6 was upregulated in a timedependent manner, mainly by the gingival fibroblasts. On one hand, MIP1 was stimulated with a low concentration (0,1ugml) of LPS by gingival fibroblasts. On the other hand, SDF1 was constitutively secreted by the same cells but its production was inhibited when challenged by a higher concentration of LPS from P gingivalis. In general, periodontal ligament fibroblasts did not show a pattern of production of these cytokines under the challenge with LPS, despite of the basal production of SDF1 in lower levels than gingival cells and the low production of MIP1 over time. The differential ability of the gingival and periodontal ligament fibroblasts to secrete these cytokines emphasizes their crucial role in the inflammatory microenvironment and in the host immune response to periodontal disease.

Fibroblastos são as células mais numerosas encontradas nos tecidos orais como gengiva, ligamento periodontal e polpa dental. Além de exercerem função estrutural, estas células também desempenham papel importante na resposta imune destes tecidos através do reconhecimento de antígenos e produção de mediadores inflamatórios e citocinas. Evidências apontam ainda para o fato de que fibroblastos não constituem um grupo único de células. Sendo assim, os objetivos deste estudo foram: (I) avaliar a produção diferencial de fibroblastos de gengiva, ligamento periodontal e polpa dental de dentes permanentes e decíduos quanto à produção das quimiocinas CCL3 e CXCL12; (II) avaliar a produção de pró-colágeno I pelas células de polpa e (III) avaliar a expressão diferencial dos fibroblastos quanto a microRNAs. Dentes recentemente extraídos (terceiros molares hígidos) e fragmentos de gengivas saudáveis de três pacientes adultos foram obtidos no Laboratório de Farmacologia e Fisiologia Clínica da Faculdade de Odontologia de Bauru. Caninos decíduos de dois pacientes com indicação para extração por motivos ortodônticos foram obtidos na Clínica de Odontopediatria da mesma unidade. Culturas primárias de fibroblastos de gengiva (n=3), ligamento periodontal (n=3) e polpa de dente permanente (n=3) e polpa dental de dente decíduo (n=2) foram estabelecidas a partir de tecidos humanos por meio de técnica de explant. Após a quarta passagem, a produção de CCL3 e de CXCL12 foi avaliada após estímulo com concentrações crescentes (0 10 µg/mL) de ácido lipoteicóico de Enterococcus faecalis (EfLTA), lipopolissacarídeo de Porphyromonas gingivalis (PgLPS) ou LPS de Escherichia coli (EcLPS) por ELISA após 1, 6 e 24 h. O RNAm para as quimiocinas no grupo estimulado com EcLPS por 24 h foi avaliado por transcrição reversa seguida de reação em cadeia da polimerase quantitativa. A produção de pró-colágeno I por células de polpa estimuladas com EfLTA e PgLPS foi avaliada por imunofluorescência. O perfil de expressão de microRNAs foi investigado por ensaio de microarranjo. A produção de CCL3 foi aumentada (p< 0,05) pelos antígenos empregados, porém de maneira mais evidente para EcLPS em células de gengiva. A quimiocina CXCL12 foi detectada em níveis basais em todos os grupos de células, porém em maiores quantidades em fibroblastos de gengiva seguidos pelos de ligamento periodontal. A adição dos antígenos diminuiu a produção de CXCL12 de maneira distinta entre células e entre antígenos (p< 0,05). Fibroblastos de polpa decídua não apresentaram qualquer alteração na produção desta quimiocina pelos antígenos (p> 0,05). No período experimental de 24 h, a expressão do RNAm para CXCL12 não foi alterada enquanto a de CCL3 não foi detectada. A produção de pró-colágeno I se mostrou aumentada (p< 0,05) na presença do desafio antigênico em células de polpa com exceção para fibroblastos de polpa permanente que apresentaram diminuição na produção desta proteína quando estimulados com EfLTA. Em condições basais, fibroblastos do mesmo doador apresentaram perfil distinto de expressão de microRNAs envolvidos com a produção das proteínas-alvo deste estudo. A expressão de imunomiRs por EcLPS também se mostrou modificada de maneira distinta entre os fibroblastos, em especial os de ligamento periodontal. Com base nestes resultados, pode-se concluir que fibroblastos de diferentes tecidos orais apresentam comportamento diferencial frente a antígenos bacterianos comumente relacionados a patologias que afetam a cavidade oral. / Fibroblasts are the dominant cells within oral tissues such as gingiva, periodontal ligament and dental pulp. Besides the architectural maintenance of the connective tissues, fibroblasts are also involved in connective tissue immune response through antigen recognition and production of inflammatory mediators and cytokines. Recent studies also demonstrated that fibroblasts do not constitute a unique group of cells. Taken this togeter, the objectives of the present study were: (I) to evaluate the production of the chemokines CCL3 and CXCL12 by human gingival, periodontal ligament as well as permanent and deciduous dental pulp fibroblasts; (II) to evaluate the production of procollagen I by dental pulp fibroblasts and (III) to evaluate the differential pattern of expression of microRNAs by the oral fibroblasts. Recently extracted teeth (non-carious third molars) and fragments of healthy gingiva from three adults were obtained at the Laboratory for Clinical Pharmacology and Physiology at Dental School of Bauru. Deciduous canines from two patients with orthodontic indication for extraction were obtained at Pediatrics Clinics of Dental School of Bauru. Primary cultures of fibroblasts from gingiva (n=3), periodontal ligament (n=3) as well as permanent pulp (n=3) and deciduous pulp (n=2) were established through an explant technique. After the fourth passage, fibroblasts were challenged with increasing concentrations (0 10 µg/mL) of Enterococcus faecalis lipoteichoic acid (EfLTA), Porphyromonas gingivalis lipopolysaccharide (PgLPS) or Escherichia coli LPS (EcLPS) for 1, 6 and 24 h. The chemokines were assessed through ELISA while the mRNA for CCL3 and CXCL12 (EcLPS at 24 h) were assessed through reverse transcription followed by quantitative polymerase chain reaction. The expression of microRNAs was screened through a microarray assay. The production of CCL3 on cell supernatants was detected in all cellular groups, with higher amounts at gingival fibroblasts. EcLPS induced more important chemokine differences compared to the other antigens. CXCL12 basal levels were higher for gingival fibroblasts followed by periodontal ligament ones, but also detected in dental pulp fibroblasts. The production of this chemokine was decreased by stimulation in a different fashion for each antigen and cell type. Deciduous pulp fibroblasts did not display any differences in CXCL12 synthesis even in the presence of the microbial challenge. No differences were detected at mRNA level for CXCL12, while no expression for CCL3 could be detected at 24 h. Increased production of procollagen type I was observed for dental pulp cells in general, with the only exception for permanent pulp cells which displayed decreased production of the protein with EfLTA. Microarray analysis showed differential expression pattern of microRNAs comparing unstimulated cells from the same donnor. EcLPS was able to alter immunomiRs expression in some of the cellular groups, in particular periodontal ligament fibroblasts. In conclusion, our results showed that fibroblasts from distinct oral tissues display differential behavior against bacterial antigens commonly related to the diseases that affect the oral cavity.

Equinodermos são bem conhecidos pelas suas grandes capacidades regenerativas, principalmente em processos mais complexos como a reposição de membros e órgãos. Porém pouco se sabe sobre processos aparentemente mais simples como a cicatrização. Tem sido descrito que um dos principais mecanismos envolvidos neste evento é o remodelamento da matriz extracelular e que existem células responsáveis por isto. Entretanto, vários detalhes do processo e do exato papel destas células ainda não são muito claros. Neste trabalho, foram estudados os estágios do processo de cicatrização em Holothuria grisea Selenka, 1867 (Holothuriidae). A lesão foi induzida através de uma incisão perfurando a parede do corpo do animal até alcançar a cavidade celomática. Através de análises histológicas, foram acompanhadas as mudanças estruturais e os mecanismos celulares que ocorrem no intervalo de doze horas a trinta dias após a injúria. Foi observado que houve um rápido fechamento da ferida através da síntese de novas fibras de colágeno, e que fibroblastos e duas populações de esferulócitos estão envolvidos neste processo. São discutidas as prováveis funções destes tipos celulares e possíveis diferenças funcionais entre os esferulócitos. / Echinoderms are well known by their regenerative capabilities, mostly in complex events such as the reconstruction of internal organs or entire body parts. However, the knowledge on apparently simpler processes such as wound healing is relatively scarce. It has been described that extracellular matrix remodeling is the main mechanism, and it involves participation of different cells populations. However, the specific function of these cell types is still under debate. In this work, the wound healing process in Holothuria grisea Selenka, 1867 (Holothuriidae) was studied. The lesion was made by an incision through the body wall up to the coelomic cavity. The local changes in cell types and the reorganization of the extracellular matrix were accompanied from 12 hours to 30 days after the injury. Soon after the wound, the organism responded with a localized contraction, followed by cell migration and synthesis of new collagen fibers. Four different cell types were observed, including two different types of spherulocytes. The probable functions of these cells are discussed.

A biomodificação radicular empregando ácido cítrico tem sido utilizada visando à reinserção dos tecidos periodontais a raízes expostas à doença periodontal. Entretanto, a grande diversidade metodológica entre os estudos ainda não possibilitou o estabelecimento de um protocolo amplamente aceito quanto à concentração e tempo de aplicação do ácido. Assim, 32 dentes extraídos por doença periodontal avançada forneceram 63 fragmentos radiculares que, após raspagem manual, foram divididos nos seguintes grupos de tratamento: Grupo AC-10-90: desmineralização com ácido cítrico a 10% em pH 1, durante 90 segundos; Grupo AC-10-120: desmineralização com ácido cítrico a 10% em pH 1, durante 120 segundos; Grupo AC-10-180: desmineralização com ácido cítrico a 10% em pH 1, durante 180 segundos; Grupo AC-50-90: desmineralização com ácido cítrico a 50% em pH 1, durante 90 segundos; Grupo AC-50-120: desmineralização com ácido cítrico a 50% em pH 1, durante 120 segundos; Grupo AC-50-180: desmineralização com ácido cítrico a 50% em pH 1, durante 180 segundos; Grupo C (controle): lavagem com soro fisiológico. Sobre as superfícies tratadas foram cultivados fibroblastos do ligamento periodontal humano por 24, 48 e 72 horas. A ampliação dos túbulos dentinários, morfologia celular e a porcentagem das superfícies radiculares recobertas por células foram avaliadas em microscopia eletrônica de varredura. As imagens microscópicas das superfícies recobertas por células foram comparadas pelo teste não paramétrico de Kruskal-Wallis seguido pelo teste de Dunn e na ampliação dos túbulos pelo teste de variância a dois critérios (ANOVA) complementado pelo teste de Tukey, em 5% de significância, ambos realizados por um programa computadorizado comparando os resultados entre os grupos. A Com exceção do grupo C, em todos os grupos houve aumento crescente da cobertura da superfície radicular por fibroblastos com o tempo. A maior área de cobertura foi apresentada pelo grupo AC-10-90 (98,82±2,57%) às 24 horas e essa diferença foi significante (p<0,001) em comparação aos grupos AC-50-90 (64,94±20,60%), AC-50-180 (56,59±35,42%) e C (0,06±0,24%). Nas demais comparações de tempo de aplicação e tempo de cultura, predominou a superioridade dos grupos tratados por ácido cítrico a 10% sobre os de 50%, porém, sem significância estatística. Todos os grupos teste foram significantemente superiores aos controle em todos os tempos de cultura. O menor valor médio para o diâmetro dos túbulos dentinários expostos pelos tratamentos foi apresentado pelo grupo AC-10-90 (4,55±0,69 &#x3BC;m) que diferiu significantemente (p<0,001) dos grupos AC-10-120 (5,33±0,95 &#x3BC;m), AC-10-180 (5,54±1,56 &#x3BC;m) e AC-50-180 (5,56±1,22 &#x3BC;m). Esse último apresentou a maior ampliação, porém sem diferença significante em relação aos demais grupos. Os fibroblastos apresentaram-se mais espalhados, achatados e com menor definição de limites nos grupos tratados com ácido cítrico a 10% do que nos de 50%, cujas células apresentavamse fusiformes e arredondadas. Concluiu-se que o ácido cítrico a 10% por 90 segundos produziu superfície mais favorável à proliferação celular com características morfológicas de estágios mais avançados de diferenciação e área de cobertura superficial por fibroblastos mais extensa no período inicial de cultura do que na concentração de 50%. A ampliação dos túbulos dentinários pareceu não influenciar a cobertura superficial por fibroblastos. Estudos subsequentes devem investigar a influência das propriedades químicas do agente biomodificador radicular para contribuir para a elucidação das diferenças produzidas no comportamento celular. / The root biomodification employing citric acid has been used in order to reattach periodontal tissues to root surface exposed to periodontal disease. However, the methodological diversity among studies has not allowed the establishment of a widely accepted protocol as the concentration and time of acid application. Thus, 32 teeth were extracted due to advanced periodontal disease, so that 63 root fragments were provided. After scaling and root planning, the fragments were divided into the following treatment groups : AC-10-90 group: demineralization with 10% citric acid at pH 1 for 90 seconds; AC-10-120 group: demineralization with 10% citric acid at pH 1 for 120 seconds; AC-10-180 group: demineralization with 10% citric acid at pH 1 for 180 seconds; AC-50-90 group: demineralization with 50% citric acid at pH 1 for 90 seconds; AC-50-120 group: demineralization with 50% citric acid at pH 1 for 120 seconds; AC-50-180 group: demineralization with 50% citric acid at pH 1 for 180 seconds; group C (control) : rinsing with saline solution. On the treated surfaces, fibroblasts from human periodontal ligament were cultured by 24, 48 and 72 hours. The enlargement of the dentinal tubules, cell morphology and the percentage of root surface covered by cells were evaluated by scanning electron microscopy. Those microscopic images from the root surfaces covered by cells were compared by the nonparametric Kruskal-Wallis test followed by Dunn\'s test and the enlargement of tubules by two variance (ANOVA) complemented by the Tukey test, both performed by a computer program comparing the results between the groups, at 5% significance. With the exception of group C, all groups showed increasing coverage of the root surface by fibroblasts over time. The largest area of coverage was presented by AC-10-90 (98.82±2.57%) at 24 hours and this difference was significant (p <0.001) compared to AC-50-90 (64.94±20.60%), AC-50-180 (56.59±35.42%) and C (0.06±0.24%). In other comparisons the application time and culture time groups treated with citric acid at 10% were superior to groups of 50%, without statistical significance. All test groups were significantly better than the control ones at all times of culture. The shortest average diameter of dentinal tubules exposed by the treatments was presented by AC-10-90 (4.55±0.69 &#x3BC;m) group that differed significantly (p<0,001) from AC-10-120 (5 groups 33±0.95 &#x3BC;m), AC-10-180 (5.54±1.56 &#x3BC;m) and AC-50-180 (5.56±1.22 &#x3BC;m). This last showed the highest enlargement, but without significant difference compared to the other groups. The fibroblasts were more spread, flattened and had less identifiable limits in the groups treated with citric acid 10% than those in 50% which cells had become rounded and spindle. It was concluded that the demineralization with 10% citric acid for 90 seconds produced more favorable surface to cell proliferation, more morphological characteristics of later stages of differentiation and larger surface area coverage by fibroblasts in the initial periods of culture than any of the groups treated with 50% citric acid. The enlargement of dentinal tubules did not seem to influence the surface coverage by fibroblasts. Subsequent studies should investigate the influence of the chemical properties of the root conditioner agent on the root surfaces in order to contribute to the elucidation of the differences produced in the cell behavior.

O objetivo deste estudo foi estabelecer cultura primária de células derivadas da granulação óssea (GO) de seres humanos para determinar seu padrão de crescimento in vitro e determinar os efeitos biológicos de três membranas reabsorvíveis feitas de colágeno (BioGide®, GenDerm®, CollaTape®) em culturas de fibroblastos gengivais humanos (FGH) e células da granulação óssea (GO). Foram coletadas amostras de tecido ósseo presente no alvéolo de cicatrização de dois pacientes adultos saudáveis sistemicamente com indicação de cirurgia periodontal regenerativa pela técnica do enxerto ósseo em neoformação. Imediatamente após a coleta, as amostras foram transportadas ao laboratório de cultura de células para estabelecimento da cultura primária. As células foram cultivadas em atmosfera úmida, contendo 5% CO2 a 37oC. A curva de crescimento das células foi determinada por meio de contagem de células viáveis. Após a caracterização da curva de crescimento, foram realizadas a caracterização da amostra por meio de determinação da atividade de fosfatase alcalina e de mineralização. Posteriormente, os efeitos de três diferentes tipos de membranas colágenas sobre a proliferação de células GO e FGH foram investigados por meio do teste MTT. As amostras foram divididas em oito grupos: (1) células FGH em meio DMEM (C-FGH); (2) células FGH em meio DMEM condicionado com membrana GenDerm (GD-FGH); (3) células FGH em meio DMEM condicionado com membrana BioGide (BG-FGH); (4) células FGH em meio DMEM condicionado com membrana ColaTape (CT-FGH); (5) células GO em meio DMEM (C-GO); (6) células GO em meio DMEM condicionado com membrana GenDerm (GD-GO); (7) células GO em meio DMEM condicionado com membrana BioGide (BG-GO); (8) células GO em meio DMEM condicionado com membrana CollaTape (CT-GO). O teste de proliferação celular mostrou que houve aumento significativo (p< 0.05; ANOVA para medidas repetidas) do número de células vitais presentes na cultura nos dias 3 (90,8%), 5 (132,50%), 7 (137,50%) e 10 (227,50%) em relação ao controle (dia 0). Foram observadas atividade de fosfatase alcalina e de mineralização in vitro. Houve aumento do número de células FGH e GO viáveis em todos os grupos (p< 0.05; ANOVA para medidas repetidas). Houve maior efeito proliferativo nas células FGH e GO nos grupos GD e CT, com diferenças estatisticamente significantes entre os grupos (p< 0.05; Mann Whitney) apenas no período de 96 horas. Esses achados sugerem que as células GO apresentam alta atividade de proliferação e síntese, sendo compatíveis com células de linhagem osteoblástica. Duas membranas colágenas testadas exerceram maior ação proliferativa tardia sobre osteoblastos, indicando sua eficácia na regeneração dos tecidos periodontais. / The aim of this study was to establish primary culture of cells derived from human bone granulation tissue (GO) in order to determine its growth pattern in vitro and the biological effects of three absorbable collagen membranes (BioGide®, GenDerm®, CollaTape®) in human gingival fibroblasts (FGH) and human bone granulation (GO) cell cultures. Samples of bone tissue present at healing sockets of two systemically healthy adults with indication of periodontal regenerative therapy by the newly forming bone were collected. Immediately after, samples were transported to the laboratory of cell culture to the establishment of primary cultures. Cells were cultivated in humid atmosphere with 95% CO2 at 37oC. Cells growth pattern were determined by counting of viable cells. After characterization of growth pattern, samples were characterized according to alkaline phosphatase activity and mineralization detected by alizarin red. Afterwards, the effects of three different types of collagen membranes on GO and FGH cells were investigated by MTT test. Samples were divided into eight groups: (1) FGH cells in DMEM (C-FGH); (2) FGH in DMEM conditioned by GenDerm® membrane (GD-FGH); (3) FGH in DMEM conditioned with BioGide® (BG-FGH); (4) FGH in DMEM conditioned by CollaTape® (CT-FGH); (5) GO cells in DMEM (C-GO); (6) GO cells in DMEM conditioned by GenDerm® (GD-GO); (7) GO cells in DMEM conditioned by BioGide® (BG-GO); (8) GO cells in DMEM conditioned by CollaTape® (CT-GO). Cell proliferation test showed a significant (p< 0.05; ANOVA for repeated measures) increase in the number of vital cells present in the culture at days 3 (90.8%), 5 (132.50%), 7 (137.50%) and 10 (227.50%) compared to control (dia 0). It was observed alkaline phosphatase activity and mineralization in vitro. There was an increase in the number of FGH and GO viable cells at all groups (p< 0.05; ANOVA for repeated measures). Greater proliferative effect at FGH and GO cells at GD and CT groups, with significant differences between groups (p< 0.05; Mann Whitney) only at 96 hs. Two of the collagen membranes tested exerted greater late proliferative effects on osteoblasts, suggesting its efficacy in the regeneration of periodontal tissues.

Enxertos gengivais livres são importantes para garantir condições necessárias para o estabelecimento da homeostasia do periodonto de proteção. O processo de inflamação não ocorre por igual em todos os tecidos conjuntivos do organismo e os fibroblastos têm a capacidade de reagir a estímulos agressivos por meio de liberação de diversas citocinas, que desempenham importante função na formação do infiltrado inflamatório. Até o presente trabalho, não há relatos na literatura acerca da comparação do comportamento dos fibroblastos que compõem a mucosa palatina não marginal e dos fibroblastos provenientes de enxerto gengival livre (EGL) marginal em resistir aos estímulos agressores que ocorrem na doença periodontal. Dessa forma, a proposta do presente trabalho foi investigar se os fibroblastos da mucosa palatina não marginal mudariam seu perfil de secreção de citocinas quando enxertados na margem gengival. Foram coletadas biópsias da mucosa palatina no momento da cirurgia de EGL (período inicial) e após 4 meses (período final) no momento da cirurgia para recobrimento radicular. Os fibroblastos foram cultivados e estimulados com LPS de Porphyromonas gingivalis (Pg) e de Escherichia coli (Ec) por 24h e 48h para avaliação comparativa da expressão de citocinas e mediadores do reparo tecidual, como: IL-6, IL-8/CXCL8, MIP-1&#x3B1;/CCL3, TGF-&#x3B2;, VEGF e CXCL16. As citocinas foram quantificadas no sobrenadante das células por meio de ensaio imunoenzimático (ELISA). Para a citocina IL-6, os fibroblastos da mucosa palatina não marginal mantiveram o mesmo perfil de secreção quando enxertados na área gengival marginal; para MIP-1&#x3B1; a secreção se mostrou aumentada de forma estatisticamente significativa pelos fibroblastos obtidos do enxerto gengival marginal após 48h de estímulo por Pg em comparação com os fibroblastos da área palatina não marginal; a secreção de IL-8 pelos fibroblastos da mucosa palatina não marginal foi maior em resposta ao desafio por LPS de Pg e os fibroblastos obtidos do enxerto gengival marginal exibiram secreção até mesmo sem o estímulo de LPS; apenas os fibroblastos do enxerto gengival marginal apresentaram secreção de TGF-&#x3B2;, mesmo na ausência de estímulo por LPS; a secreção de VEGF e CXCL16 não foi detectada pelos fibroblastos analisados. Conclui-se que os fibroblastos provenientes de uma mucosa palatina não marginal parecem se adaptar às condições locais quando enxertados na área gengival marginal, oferecendo evidência de sua participação efetiva na produção de mediadores inflamatórios importantes para o processo de homeostasia do periodonto marginal. / Free gingival grafts are important to ensure conditions for the establishment of homeostasis of the periodontal soft tissues. The process of inflammation does not occur the same way in all connective tissues and fibroblasts have the ability to respond to aggressive stimuli through the release of various cytokines, which play an important role in the inflammatory infiltrate formation. In literature, there are no studies comparing the behavior of fibroblasts from palatal mucosa (not marginal) and fibroblasts from marginal free gingival graft (FGG) regarding their resistance towards periodontal disease aggressive stimuli. Thus, the purpose of this study was to investigate whether fibroblasts from the palatal mucosa behave differently when grafted to the gingival margin considering their mechanism of cytokine secretion. Biopsies from the palatal mucosa were collected at the time of FGG surgery (initial period) and after 4 months (final period) when surgery for root coverage was performed. The fibroblasts were cultured and stimulated with LPS of Porphyromonas gingivalis (Pg) and Escherichia coli (Ec) for 24 and 48 hours in order to make a comparative evaluation of cytokines and mediators of tissue repair expression, such as IL-6, IL-8/CXCL8, MIP-1&#x3B1;/CCL3, TGF-&#x3B2;, VEGF and CXCL16. Cytokines were measured in the cell supernatant by enzyme immunoassay (ELISA). For cytokine IL- 6, fibroblasts from palatal mucosa maintained the same secretion pattern when grafted to the gingival margin; for MIP-1&#x3B1; the secretion was significantly increased by fibroblasts from the marginal gingival graft after 48 hours of stimulation with Pg when compared to palatal mucosa fibroblasts; IL-8 secretion by palatal mucosa fibroblasts did not increase in response to Pg LPS challenge and fibroblasts from marginal gingival graft showed secretion even without the stimulus of LPS; only fibroblasts from marginal gingival graft showed secretion of TGF-&#x3B2;, even in the absence of LPS stimulation; VEGF and CXCL16 secretion by fibroblasts was not detected. It was concluded that fibroblasts from palatal mucosa seem to adapt to local conditions when grafted to the gingival margin area, providing evidence of its effective participation in the homeostasis of marginal periodontium through the production of important inflammatory mediators.