Este estudo avaliou a efetividade de uma nova membrana bioabsorvível com propriedades mecânicas e químicas mais adequadas para o uso em tendões. A avaliação foi realizada em coelhos submetidos a reconstrução da porção gastrocnêmia do tendão calcâneo. Foi feita uma avaliação prévia das propriedades mecânicas da membrana com uso de dinamômetro digital que demonstrou capacidade de deformação elástica mínima de 100%. Todos os coelhos foram submetidos a tenotomia e reparo da porção gastrocnêmia do tendão direito, após isso foram randomicamente separados em grupos envelopado com membrana e controle. A extração foi realizada nos seguintes períodos: sete, 14 e 28 dias. A avaliação foi realizada através da macroscopia, histologia, mensuração objetiva do colágeno à luz polarizada pelo image-J®, mensuração de glicosaminoglicanos sulfatados e expressão gênica de proteoglicanos. Na avaliação macroscópica o grupo com membrana apresentou menos aderência e melhor direcionamento das fibras e tecido mais homogêneo em 14 e 28 dias, p=0,02 e 0,03 respectivamente. Na histologia a Classificação de Watkins modificada apresentou as seguintes médias: 14,67±0,42 membrana e 12,67±0,56 sem membrana, p=0,03 em 14 dias, e 19,88±0,83 membrana e 17,25±0,62 sem membrana, p=0,02 em 28 dias. Na mensuração do colágeno as médias dos valores de cinza(mvc) o colágeno tipo III foram de 17,97±1,83 membrana e 12,63±1,07 sem membrana p=0,03 em 14 dias. Para o colágeno tipo I as médias foram de 2,41±0,33mvc membrana e 1,31±0,18mvc sem membrana p=0,01 em 14 dias e 7,30±0,63mvc membrana e 2,92±0,32mvc sem membrana p < 0,0001 em 28 dias. A média dos GAGs foi avaliada em três porções do tendão, proximal, central e distal, em ug/mg de tecido seco. Em sete dias apresentou diferença significativa apenas na porção distal 0,80±0,04 com e 0,38±0,04 sem membrana para condroitin-sulfato em 14 dias não apresentou diferenças entre os grupos. O dermatan-sulfato apresentou diferença estatisticamente significante em 7 dias apenas na porção central 0,42±0,09 com membrana e 1,29±0,67 sem membrana p=0,02. Em 14 dias não foram observadas diferenças entre os grupos. Houve grande variabilidade na expressão gênica no teste das amostras com beta-Actina e GAPDH levando a resultados inconclusivos ou não variação entre os grupos que pode sugerir não variabilidade na expressão gênica dos GAGs no período de 28 dias. Os dados fornecidos por esse trabalho mostram que a envelopagem com a membrana bioabsorvível promoveu aceleração dos processos cicatriciais da porção gastrocnêmia do tendão calcâneo de coelhos / This study assessed the effectiveness of a new absorbable membrane, that presents mechanical and chemical features more suitable to tendons, in rabbit tendons. Before the animal model assessments a mechanical study of the membrane was carried out demonstrating that the minimal capability for elastic deformation of the membrane was more than 100%. All rabbits underwent to tenotomy and reconstruction of the right gastrocnius tendons, thereafter they were randomly divided in tendon wrapped by the membrane and control groups. Extraction was performed in the following periods of time: seven, 14 and 28 days. Assessments used macroscopy, histology, objective collagen assessment by using polarized light and Image-J® program in mean of gray values(mgv), sulphated glycosaminoglycans, genetic expression of proteoglycans. In the macroscopic 14 and 21-day assessments the membrane group presented less adherences p=0.02 and p=0.03 respectively. The modified Watkins classification: 14,67±0,42 membrane and 12,67±0,56 without membrane p=0,03 for 14 days; 19,88±0,83 membrane and 17,25±0,62 without membrane p=0,02 for 28 days. The type III collagen were 17,97±1,83 membrane and 12,63±1,07 without membrane p=0,029 for 14 days. For type I collagen were 2,41±0,33 membrane and 1,31±0,18 without membrane p=0,01 for 14 days and 7,30±0,63 memebrane and 2,92±0,32 without membrane p < 0,0001 for 28 days. The glycosaminoglycans were measured in 3 tendon portions, distal, central and proximal, by using ug/mg of dry tissue. In seven days just the distal part presented statistical differences 0,80±0,04 membrane and 0,38±0,04 without membrane, for 14 days no differences were found for Chondroitin-Sulphate. For Dermatan-Sulphate the central part of the tendon 0,42±0,09 and 1,29±0,67 p=0,02, for 14 days no differences were found. There was high variability for beta-actin and GAPDH for the samples in 28 days with inconclusive results that may mean no variability in gene expression of GAGs at this time period. Results as mentioned above demonstrated that the wrapped tendons by the new membrane presented acceleration in the healing processes for gastrocnemius tendons of New Zealand Rabbits

Os eventos celulares e extracelulares que ocorrem durante o processo de osseointegração do titânio (Ti) são bastante influenciados por suas propriedades de superfície, como morfologia, topografia e composição química. A modificação bioquímica da superfície do Ti consiste em imobilizar proteínas ou peptídeos nessa superfície com a finalidade de induzir respostas celulares e teciduais específicas na interface osso-implante que acelerem ou aumentem a osseointegração. O objetivo deste estudo foi avaliar o desenvolvimento do fenótipo osteoblástico em culturas de células crescidas sobre Ti revestido com colágeno tipo I. Para tanto, células osteoblásticas derivadas de fragmentos ósseos do processo alveolar de humanos foram cultivadas sobre discos de Ti usinados revestidos (Ti-col) ou não (Ti-usinado) com colágeno tipo I e foram avaliados os seguintes parâmetros: adesão, morfologia e proliferação celulares, síntese de proteína total, atividade de fosfatase alcalina (ALP), formação de matriz mineralizada, e expressão de genes marcadores do fenótipo osteoblástico por reação em cadeia da polimerase em tempo real (PCR em tempo real). O Ti-col alterou o crescimento e a expressão gênica das culturas e não teve efeito na adesão e morfologia celulares, síntese de proteína total, atividade de ALP e formação de matriz mineralizada comparado ao Ti-usinado. Esses resultados indicam que a superfície Ti-col pode favorecer um maior crescimento da cultura durante a fase proliferativa e um aumento e/ou aceleração da diferenciação, como indicado por alterações na expressão gênica de marcadores do fenótipo osteoblástico. Portanto, essa modificação de superfície pode ter um impacto nos processos de reparo e remodelação do tecido ósseo adjacente a implantes, favorecendo a ocorrência de maior formação óssea. / Cellular and extracellular events that occur during titanium (Ti) osseointegration process are highly influenced by its surface properties, such as morphology, topography and chemical composition. The objective of biochemical modification of Ti is to immobilize proteins or peptides on its surface in order to induce specific cellular and tissue responses at the boneimplant interface in order to accelerate or enhance osseointegration. The aim of this study was to evaluate the osteoblastic phenotype development in cells grown on collagen type I-coated Ti surface. Osteoblastic cells from human alveolar bone fragments were cultured on turned Ti either coated with collagen type I (col-Ti) or not (turned-Ti) and the following parameters were assessed: cell adhesion, morphology, and proliferation, total protein content, alkaline phosphatase (ALP) activity, bone-like formation and gene expression of osteoblastic markers by real-time polymerase chain reaction (real-time PCR). Col-Ti altered culture growth and gene expression of osteoblastic markers without affecting cell adhesion, morphology, protein synthesis, ALP activity, and matrix mineralization. These results demonstrated that col-Ti favours cell growth during the proliferative phase and osteoblastic differentiation, as demonstrated by changes in mRNA expression profile during the matrix mineralization phase, suggesting that this Ti surface modification may affect the processes of bone healing and remodelling.

Osteogenesis imperfecta is an inherited disorder caused mainly by collagen type I genes mutations, COL1A1 and COL1A2. These mutations affect especially connective tissue. Disease is characterized by fragile bones, deformations and increased frequency of fractures. It's worldwide extensive disorder regardless of age, sex, nationality or races. The incidence is 1: 16 - 20 000 births. Currently, we described nine clinically distinct forms of Osteogenesis imperfecta. Only the first four types OI, type I-IV, are caused by collagen type I genes mutations . In these nine types there are distinguished mild and severe forms. Type II and III are lethal forms, death occur offen during prenatal period or in the first days of the life affected individuals. Characteristic clinical features of collagen forms OI are an increased incidence of fractures, deformations of bones, blue sclera, hearing loss, Dentinogenesis imperfecta small or subnormal growth (Marini, 2010). This study alignment is mainly the description of the clinical forms, exploring the molecular basis of disease and determine the relationship between the type and position of the mutation and the resulting phenotype of affected individuals. We have analysed exons 31-40, including associated non-coding regions, of the COL1A1 gene (so-called MLBR =...

No description available.

Yes / Studies have been conducted to highlight the anti-inflammatory and immunosuppressive properties of synthetic cannabinoids as well as their potential for cartilage repair. Various wound healing techniques can be used to investigate the mechanisms of chondrocyte repair in monolayers or three dimensional tissues constructs. In this work the effect of WIN55, 212-2 (WIN-2) on nitric oxide (NO) and matrix metalloproteinase-2 (MMP-2) expressed by wounded chondrocyte monolayers was investigated. Moreover, expression of collagen type-I and type-II, fibronectin and S100 proteins were detected using immunofluorescence and quantitatively verified using ELISA based techniques following treatment with 1 μM and 2 μM of WIN-2. Treating chondrocytes with 1 μM of WIN-2 significantly increased expression of collagen type-II, fibronectin and S100, and significantly reduced collagen type-I expressions as compared to the control groups. On the other hand, both concentrations of WIN-2 significantly reduced the expression of the inflammation markers NO and MMP-2 in a dose dependent manner. These findings highlight the potential use of the synthetic cannabinoids for improving cartilage healing properties as well as acting as an anti-inflammatory agent which could be used to enhance tissue engineering protocols aimed at cartilage repair.

Osteogenesis imperfecta (OI) is a heterogeneous disease of connective tissue, the cardinal symptom being fractures and severity ranging from mild to lethal. Dominant mutations in collagen I, encoded by COL1A1 and COL1A2, cause &gt;90% of cases. To delineate genotype-phenotype correlations and pharmaco-genetic response, collagen I was sequenced in 150 unrelated Swedish families and clinical data were collected in Paper I. Mutation type, gene affected, and N- to C-terminal location correlated with phenotype and severity. Bisphosphonate response assessed by calculated yearly change in lumbar spine bone mineral density (BMD) was inversely related to age and BMD at treatment initiation. Mutations associated with a more severe phenotype exhibited an increased response after 2 years; however, all types of OI responded well. To investigate the effect of naturally occurring variations in collagen I, the only common coding single nucleotide polymorphism (rs42524 in COL1A2) was genotyped in 2004 healthy men in Paper II. Heterozygous genotype was associated with decreased BMD and an increased risk of stroke. An adolescent with repeated fractures despite a markedly high BMD harbored a unique C-terminal procollagen cleavage-site mutation in COL1A1, which motivated extensive investigations in concert with a similar COL1A2 case in Paper III. The probands were found to have impaired procollagen processing, incorporation of collagen with retained C-propeptide in matrix and increased mineral to matrix ratio, which demonstrates that C-propeptide cleavage is crucial to normal bone mineralization and structure. Bisphosphonate therapy has insufficient effect in OI, and as classical OI is a dominant disorder severe cases would benefit from silencing of the mutated allele. In Paper IV and V small interfering RNAs (siRNAs) were used to allele-specifically target primary human bone cells heterozygous for I) a coding polymorphism in COL1A2 and II) insertion/deletions in the 3’UTR of COL1A1 and COL1A2. Results were promising with altered allele ratios and decreased mRNA levels in the predicted fashion. To summarize, this thesis found that collagen I is crucial to bone and connective tissue and that collagen I mutations create markedly diverse phenotypes. Age, BMD and pharmaco-genetic effects influence the response to bisphosphonate therapy in individuals with OI; however, novel approaches are needed. Utilizing allele-specific siRNAs may be a way forward in the treatment of severe OI.

Le but de cette étude était d’évaluer si la bone morphogenetic protein (BMP)-2 pouvait aider à contrôler le phénotype de chondrocytes humains dans des conditions de culture à long terme nécessaires pour la transplantation de chondrocytes autologues (TCA). Nous avons aussi évalué le potentiel de la BMP-2 comme facteur de réparation du cartilage, en combinaison avec un biomatériau à base de collagène, pour étendre la technique aux lésions arthrosiques. Des chondrocytes humains ont été cultivés selon la procédure utilisée pour la TCA. Nous avons évalué la réponse des chondrocytes à la BMP-2 en culture monocouche ou dans les éponges de collagène par des analyses par PCR en temps réel, par Western blotting et Immunohistochimie.L’ajout de BMP-2 améliore le caractère chondrogénique des chondrocytes humains amplifiés en monocouche. L’effet stimulateur de la BMP-2 sur l’expression du collagène de type II a été observé au niveau des gènes mais aussi des protéines, ce qui est une propriété essentielle pour la reconstruction d’une matrice cartilagineuse. Nos résultats ont aussi montré que dans des chondrocytes tout d’abord amplifiés en monocouche puis cultivés en éponges de collagène en présence de BMP-2, la BMP-2 est capable de restaurer l’expression du gène COL2A1 et la synthèse de collagène de type II qui avaient été perdues pendant l’amplification. De manière importante, aucun signe de maturation hypertrophique ou d’induction ostéogénique n’a été détecté. Cette étude est la première à révéler le bénéfice de l’ajout de BMP-2 à des chondrocytes humains comme un agent thérapeutique pour la réparation du cartilage. / The aim of this study was to investigate if bone borphogenetic brotein (BMP)-2 could help to control human chondrocytes phenotype in long-term culture conditions necessary for autologous chondrocyte implantation (ACI). We also evaluated the potential of BMP-2 as a repair factor in combination with collagen-based biomaterials, to extend the technique to osteoarthritic lesions. Human chondrocytes were cultured independently, according to the procedure used for ACI. We evaluated the responsiveness of chondrocytes to BMP-2 when cultured in monolayer or within collagen sponges using Real-time PCR, Western blotting and Immunohistochemistry. Exogenous BMP-2 improved the chondrogenic character of human chondrocytes when amplified in monolayer. The stimulatory effect of BMP-2 on type II collagen expression was observed not only at the mRNA level but also at the protein level, and this is crucial for cartilage matrix reconstruction. Our data with human chondrocytes first amplified in monolayer then cultured in collagen sponges in the presence of BMP-2 have revealed that BMP-2 is able to restore COL2A1 gene expression and type II collagen synthesis that were lost during the amplification step. Importantly, no sign of hypertrophic maturation or osteogenic induction was detected beside the chondrogenic stimulatory effect of BMP-2. This study is the first to reveal the benefit of adding exogenous BMP-2 to human chondrocytes as a therapeutic agent for cartilage repair.

Le syndrome d'Ehlers-Danlos (SEDv) est une maladie artérielle génétique autosomique dominante, affectant le collagène de type III au sein de la matrice extracellulaire de la paroi artérielle notamment. Les patients atteints de SEDv ont une prédisposition aux ruptures artérielles, digestives et utérines qui font toute la sévérité de cette maladie. Les mutations du gène COL3A1 codant pour le collagène de type III sont le plus souvent des mutations hétérozygotes faux-sens, responsables de la substitution d'une glycine par un autre acide aminé, affectant la structure en triple hélice du collagène de type III. Des variants d'un site d'épissage, des insertions-délétions sont également rencontrées, et plus rarement des mutations faux-sens n'affectant pas une glycine, ou des mutations responsables d'haploinsuffisance. Les mutations du COL3A1 sont presque exclusivement privées, et une corrélation entre le phénotype observé et les mutations retrouvées n'a jamais été mise en évidence. Nous avons rapporté l'expérience du centre de référence français du SEDv sur 215 patients, et retrouvé une sévérité de la maladie plus importante chez ceux avec une substitution glycine, ou une insertion/délétion du cadre de lecture dans région de la triple hélice comparativement aux autres génotypes: variants responsables d'haploinsuffisance, variants faux-sens n'affectant pas une glycine, ou les altérations des extrémités N ou C-terminales. Par ailleurs, le phénotype de ces 3 derniers groupes de génotype ne rassemblait pas l'ensemble des symptômes habituellement décrits dans le SEDv et notamment pas de complication digestive. Afin de mieux comprendre l'altération des propriétés biomécaniques de la paroi artérielle des patients atteints de SEDv nous avons utilisé une nouvelle technologie ultrasonore, ultrafastécho, permettant de visualiser et mesurer la vitesse de l'onde de pouls (VOP) localement au niveau carotidien et tout au long du cycle cardiaque. La VOP est un marqueur de rigidité artérielle bien étudié dans l'athérosclérose, et connu pour être un facteur indépendant de mortalité cardiovasculaire. Nous avons établi des valeurs normales des paramètres de l'ultrafastécho chez 102 volontaires sains et analysés 37 patients avec SEDv. Cette étude n'a pas retrouvé de différence de la VOP, donc de rigidité artérielle, en début de systole. En revanche, au cours du cycle cardiaque on a pu observer une moindre rigidification de la paroi artérielle avec l'augmentation de la pression artérielle chez les patients SEDv. Nous avons poursuivi nos explorations par ultrafastécho sur un modèle murin haploinsuffisant pour le collagène de type III (souris Col3a1 hétérozygote) et retrouvé le même profil de réponse. En effet une moindre augmentation de la rigidité artérielle alors que la pression artérielle était augmentée par perfusion de vasopresseur était constatée chez les souris col3a1 hétérozygotes comparativement aux souris sauvages. En conclusion, l'altération du collagène de type III dans le SEDv affecte les propriétés biomécaniques de la paroi artérielle des patients, avec notamment une moindre rigidification lors de l'augmentation de la pression artérielle. Nos travaux ont permis d’affiner la physiopathologie du SEDv, de préciser le phénotype vasculaire par une nouvelle mesure de la VOP et ouvrent des pistes de recherche thérapeutiques d'un traitement augmentant la rigidité artérielle afin de tenter de réduire les risques de ruptures artérielles. / Vascular Elhers-Danlos syndrome (vEDS) is an autosomal dominant genetic vascular disease, affecting the collagen type III, a component in the extracellular matrix of the arterial wall. Patients with vEDS are prone to arterial, intestine or uterine ruptures, which explain the severity of the disease. Mutations in COL3A1, gene encoding for collagen type III are usually heterozygous missense mutations responsible for the substitution of a glycine amino acid for another, which affects the triple helical conformational structure of the collagen type III. Variants of a splice site, deletions/insertions, are also encountered, and more rarely missense mutations not affecting a glycine residue, or alterations responsible for haploinsufficiency. The COL3A1 mutations are almost exclusively private, and a genotype/phenotype correlation has not been clearly studied. We reported the experience of the French reference center for vEDS of 215 patients and found a greater severity of the disease in those with a glycine substitution, or in frame insertion / deletion within the triple helix domain than in other genotypes: responsible variants of haploinsufficiency, missense variants not affecting glycine, or alteration of the N- or C-terminal ends. Furthermore, the phenotype of these last three genotype groups did not combine the complete phenotype described in vEDS especially no gastrointestinal complication. To better understand the alteration of the biomechanical properties of the arterial wall of patients with vEDS we used a new ultrasound technology, ultrafastecho, to visualize and measure the pulse wave velocity (PWV) locally on carotids, over the cardiac cycle. The PWV is a marker of arterial stiffness studied in atherosclerosis, and well known to be an independent risk factor for cardiovascular mortality. We have established normal values ultrafastecho parameters in 102 healthy volunteers and 37 patients with vEDS. This study found no difference in PWV, thus arterial stiffness, in early systole cardiac at diastolic blood pressure. However, in patients with vEDS, weaker stiffening of the arterial wall was observed when blood pressure increases during the cardiac cycle. We continued our explorations by ultrafastecho on a mouse model of vEDS, haploinsufficient for the collagen type III (Col3a1 heterozygous mice). We figured out that Col3a1 heterozygous mice presented the same response profile. Indeed a smaller increase in arterial stiffness while blood pressure was increasing secondary to vasopressor infusion was revealed in the mice compared to the wild mice. In conclusion, alterations of collagen type III in the vEDS affect the biomechanical properties of the arterial wall of the patient, through lower stiffening during the increase of blood pressure over the cardiac cycle. This provides a therapeutic approach for targeting treatment increasing arterial stiffness in vEDS in order to reduce the risk of arterial rupture.

O objetivo deste estudo foi avaliar e comparar a reparação tecidual após incisões com os lasers de CO2 e de diodo, bisturi elétrico e convencional em língua e pele de 30 ratos Wistar. Incisões de 5 mm de comprimento por 2 mm de profundidade na pele, e de 2,5 mm de comprimento por 1 mm de profundidade na língua, foram feitas nestes tecidos, e os animais sacrificados nos intervalos de zero, 24, 48, 72 horas, 7 e 14 dias após as intervenções. Cortes histológicos foram obtidos das incisões e submetidos a 3 tipos de análises: quantificação do dano tecidual, de mastócitos e da densidade de colágeno tipo I. Os dados foram submetidos à análise estatística pelo teste ANOVA de Kruskal-Wallis e pelo teste de comparações múltiplas de Turkey-Kramer, com nível de significância estabelecida para P < 0,05. Os resultados mostraram que o dano tecidual na pele das incisões realizadas com lasers e bisturi elétrico foi significativamente maior do que o do bisturi convencional (P < 0,05). Quanto às incisões na língua, houve diferença significante de menor dano tecidual resultante da incisão do bisturi convencional comparado com o das incisões realizadas com laser de CO2 2 W, laser de diodo 4 W e bisturi elétrico (P < 0,05). A quantificação de mastócitos mostrou diferenças estatísticas entre as incisões realizadas com bisturi convencional em relação às outras incisões (lasers e bisturi elétrico), principalmente nas 48 e 72h, tanto na pele quanto na língua. Quanto à quantificação de colágeno, apenas no 7º dia houve diferença estatisticamente significante, ocorrendo maior quantidade de colágeno tipo I somente na incisão com bisturi convencional comparada com a do bisturi elétrico (P < 0.05). No 14º dia, os dados morfométricos de colágeno foram semelhantes em todas as técnicas utilizadas. Concluímos que no período final analisado do processo reparacional, os dados morfométricos foram semelhantes em todas as técnicas utilizadas, apesar das diferenças ocorridas quanto ao dano tecidual, quantificação de mastócitos e colágeno tipo I no início do processo. Em princípio, dentro de um mesmo padrão de incisão, todos os instrumentos cirúrgicos geraram um processo reparacional semelhante, variações entre eles podem estar associadas às características do tecido, como foi observado entre a pele e mucosa. / The aim of this study was to quantify and compare the healing process after incision with CO2 (2 W e 4 W) and diode lasers (2 W and 4 W), electrosurgery (2 W) and scalpel in the skin and tongue of Wistar rats (30 animals were used). One incision of each technique (6 in total) of 5 mm long and 2 mm deep was made in the dorsal skin and dorsal tongue. The animals were sacrificed at zero, 24, 48, 72 hours, 7 and 14 days after incisions. Histological sections were made from the wound areas and subjected to analyses of area of tissue damage, quantification of mast cells and density of collagen type I. The data were submitted to the ANOVA of Kruskal-Wallis and compared by Turkey-Kramer. The level of significance was set at 5% (P < 0.05). The results showed difference concerning area of tissue damage, occurring significant statistically difference between the incisions with scalpel compared with those of other techniques (lasers and electrosurgery) in skin (P < 0.05). On the tongue, there was statistical difference, with less tissue damage on scalpel incision compared with that of CO2 (2 W) and diode lasers (4 W) and electrosurgery incisions (P < 0.05). The quantification of mast in the incisions showed statistical differences between the incisions, especially in 48 and 72h, both on the skin and tongue. Concerning the collagen quantification, statistical difference was found only in 7 th day, the collagen types I was only more evident on scalpel incision than with the electrosurgery (P < 0.05). In 14 th day, the morphometric data were similar in all types of incisions. Based on these results, it is possible to conclude that at the end of the analyzed period, the morphometric data were similar in all techniques, even though there were differences concerning tissue damage, quantification of masts cell and collagen type I at the beginning of the process. Additionally, the healing process proceeds similarly in all this technique as long as the incisions are made in a similar pattern; variations may occur depending on the type of the tissue, as was shown here between the skin and tongue.

Introdução: A imunização de coelhos saudáveis com colágeno do tipo V (COLV) reproduz as principais manifestações da esclerose sistêmica (ES), incluindo fibrose, vasculopatia e produção de autoanticorpos específicos da doença. Estudos preliminares mostraram que, tanto na derme de animais imunizados com COLV (COLV-IM), como na derme de pacientes com ES, observa-se deposição aumentada de COLV anômalo, mas não se sabe qual a relevância clínica deste achado. O remodelamento da matriz extracelular é precoce nos animais COLV-IM, ocorrendo já no sétimo dia após a imunização, o que sugere que o COLV esteja relacionado com a injúria endotelial, evento primário envolvido na patogênese da ES. Desta forma, os objetivos do presente estudo foram avaliar a expressão de COLV na derme de controles saudáveis e de pacientes com ES e sua correlação com espessamento cutâneo, atividade e duração da doença; assim como pesquisar uma possível associação entre a deposição deste colágeno na derme com a expressão de marcadores de apoptose e de ativação endotelial em pacientes e no modelo animal induzido pela imunização com COLV. Pacientes e Métodos: Biópsias de pele de pacientes com ES (N=18, 6 com doença precoce e 12 com doença tardia) e de controles (N=10) pareados por idade e sexo, assim como biópsias de pele de coelhos imunizados com COLV + adjuvante de Freund (COV-IM, N=6) ou adjuvante de Freund (N=6) foram avaliadas. Nos pacientes com ES, o espessamento cutâneo foi avaliado por meio do escore de Rodnan Modificado (MRSS) e a atividade da doença foi calculada pelo índice de atividade de Valentini. Para realizar a quantificação por histomorfometria, o COLV na derme foi identificado por imunofluorescência. Caspase-3, endotelina-1, CTGF, TGF e VEGF nas células endoteliais dérmicas foram marcados por imunohistoquímica. Nos pacientes e nos controles, o COLV proveniente da cultura de fibroblastos dérmicos foi quantificado por PCR RT em tempo real e caracterizado por eletroforese, imunoblotting e reconstrução tridimensional, por meio da microscopia confocal. Resultados: O depósito de COLV foi maior na derme de pacientes com doença precoce, quando comparados aos controles e aos pacientes com doença tardia. A atividade e a duração da ES estiveram associadas com o depósito de COLV. A expressão de RNA mensageiro das cadeias COLV1 COLV2 foi aumentada em relação aos controles e a reconstrução tridimensional confirmou a presença de fibras anômalas de COLV. Observou-se maior expressão de caspase-3, endotelina-1, CTGF, TGF e VEGF nas células endoteliais dos pacientes com ES, quando comparados aos controles. Houve correlação positiva entre o depósito de COLV e a expressão de caspase-3, endotelina-1 e CTGF. Ao comparar-se os coelhos COLV-IM com os controles, observou-se aumento significativo da expressão de COLV aos 7 dias e de endotelina-1 aos 210 dias após a imunização. Embora de maneira não significativa, verificou-se maior expressão de caspase-3, CTGF e VEGF nos animais COLV-IM e, quando os animais foram comparados ao longo do tempo, percebeu-se maior expressão de COLV no sétimo dia após a imunização na derme dos animais COLV-IM, diminuindo no trigésimo dia e voltando a subir aos 75 dias e aos 210 dias. A caspase-3 e a endotelina-1 comportaram-se de maneira semelhante. Conclusão: Estes resultados sugerem que o COLV possa agir como um possível gatilho envolvido na patogênese da ES, agindo como um indutor de ativação e de apoptose endotelial, que por sua vez poderia resultar em maior expressão de COLV, perpetuando o processo de remodelamento observado na pele dos pacientes com ES / Introduction: The immunization of healthy rabbits with type V collagen (COLV) reproduces the main characteristics of systemic sclerosis (SSc), such as fibrosis, vasculopathy and specific auto-antibodies. Preliminary studies demonstrated that both COLV-immunized rabbits (COLV-IM) and SSc patients exhibit increased expression of abnormal COLV in the dermis, but the clinical relevance of this finding is unknown. The remodeling of the extracellular matrix is an early event in COLV-IM rabbits that can be detected by the seventh day after immunization; this observation suggests that COLV is involved in endothelial injury, one of the first manifestations of the disease. Thus, the objectives of this study were to evaluate COLV expression in the dermis of healthy controls and SSc patients and to determine the correlation of this expression with skin thickness, disease activity and duration and search for a possible association between this collagen with apoptosis and activation of endothelial cells markers in patients and in animal model induced by immunization with COLV. Patients and Methods: Skin biopsies from 18 patients (6 early-stage and 12 late-stage) and 10 healthy controls as well as skin biopsies from rabbits immunized with COLV (COLV-IM) and Freund adjuvant (N=6) or Freund adjuvant alone (N=6) were evaluated. Skin thickening assessment was performed with the Modified Rodnan Skin Score (MRSS), and activity was calculated using the Valentini Disease Activity Index. To perform quantification by histomorphometry, COLV was identified by immunofluorescence, and caspase-3, endothelin-1, CTGF, TGF and VEGF in dermal endothelial cells were labeled by immunohistochemistry. In SSc patients and healthy controls, COLV from dermal fibroblast culture was quantified by real-time RT-PCR and characterized by electrophoresis, immunoblotting and tridimensional reconstruction by confocal microscopy. Results: COLV deposition was increased in the dermis of the patients with early disease compared with the healthy controls and the patients with late disease. SSc activity and disease duration were associated with dermal COLV deposition. COLV1 and COLV2 mRNA expression levels were higher in SSc, and a tridimensional reconstruction of SSc dermal heterotypic fibers confirmed the presence of abnormal COLV. The dermal endothelial cell expression of caspase-3, endothelin-1, CTGF, TGF and VEGF was higher in the SSc patients than in the controls. There was a positive correlation between COLV deposition and caspase-3, endothelin-1 and CTGF expression. When the COLV-IM rabbits were compared with the controls, there was a significant increase in the expression of COLV 7 days after the immunization and a significant increase in the expression of endothelin-1 210 days after the immunization. The expression of caspase-3, CTGF and VEGF was higher in the COLV-IM animals than in the control rabbits, although not significantly, and when the rabbits were compared over time, the expression of COLV was higher in the dermis of the COLV-IM animals 7 days after immunization, decreasing at 30 days and increasing again at 75 and 210 days. Caspase-3 and endothelin-1 exhibited similar behavior. Conclusion: these results suggest that COLV can be a possible trigger involved in the pathogenesis of SSc, acting as an inducer of endothelial apoptosis and activation that could result in higher expression of COLV, perpetuating the remodeling process observed in SSc skin