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Efeito imunomodulatório das lectinas de Synadenium carinatum (ScLL) e Artocarpus heterophylus (Artin M) no controle da toxoplasmose
Full text linkScLL and Artin M are lectins from the Synadenium carinatum latex and Artocarpus heterophyllus seeds that have important role in modulation of immune responses to pathogens. Considering that there are no reports in the literature focusing in the role of these lectins for toxoplasmosis treatment and that this protozoan disease is a serious health public problem caused by Toxoplasma gondii, the aim of this study was to evaluate the immunomodulatory effect of ScLL and Artin M in treatment of toxoplasmosis. First, we performed a cytotoxicity assays in bone marrow-derived macrophages (BMDMs) from C57BL/6 mice with different lectin concentrations. After, we investigated the in vitro cytokine and nitric oxide (NO) production by macrophages derived from BMDM cells, when stimulated with different lectin concentrations. We found that amounts higher than 1.8 μg of ScLL were cytotoxic for host cells, whereas Artin M had no cytotoxic effect. Also, ScLL presented high capacity to induce pro-inflammatory cytokine in macrophages, such IL-12, while Artin M had high potential to induce both pro and anti-inflammatory profile, by IL-10 and IL-12 production. Further, both lectins were able to increase macrophages NO levels. Hence, we evaluated the treatment effect of ScLL and Artin M in C57BL/6 mice infected by ME-49 strain of T. gondii. The animals were infected and treated with ScLL, Artin M, Artin M plus ScLL or sulfadiazine, and analyzed for cytokine production, brain parasite burden and mortality. Our results demonstrated that ScLL and Artin M were able to increase cytokines levels also in in vivo model, presenting stronger immunostimulatory effect. In addition, parasite burden was lower on mice treated with ScLL or Artin M plus ScLL. Also we found a higher survival rate in animals treated with ScLL compared to untreated. Overall, our findings suggests that the immunomodulatory mechanisms mediated by lectins ScLL and Artin M can contribute to the control of T. gondii infection.Mestre em Imunologia e Parasitologia AplicadasAs lectinas ScLL e Artin M extraídas, respectivamente, do látex de Synadenium carinatum e da semente de Artocarpus heterophylus têm um importante papel na modulação da resposta imune contra patógenos. Ainda não relatos na literatura focando no papel destas lectinas no tratamento da toxoplasmose, doença causada pelo Toxoplasma gondii, que representa um sério problema de saúde pública. Portanto, o presente estudo objetiva avaliar o efeito imunomodulatório destas lectinas no controle da infecção pelo T. gondii. Primeiro nós avaliamos a citotoxicidade de diferentes concentrações destas lectinas em macrófagos derivado de medula óssea (BMDMs) de camundongos C57BL/6. Após, investigamos a produção de citocinas e óxido nítrico (NO) em BMDMs com estímulo em diferentes concentrações de lectinas. Nossos resultados demonstram que quantidades maiores do que 1.8 μg de ScLL foram tóxicas para os macrófagos, ao passo que a Artin M, nas concentrações testadas, não apresentaram efeito citotóxico. Além disso, ScLL induziu maiores níveis de IL-12, enquanto Artin M induziu maior produção tanto de IL-12 como de IL-10. Ambas as lectinas foram capazes de induzir o aumento nos níveis de NO. Também avaliamos o efeito da ScLL e Artin M no controle da infecção causada por de T. gondii cepa ME-49 em camundongos C57BL/6. Os animais foram infectados e tratados com as lectinas ScLL e/ou ArtinM ou sulfadiazina, e foram avaliados a produção de citocinas, carga parasitária cerebral e mortalidade. Nosso resultados demonstram que ScLL e Artin M também foram capazes de induzir aumento nos níveis de citocinas in vivo. Além disso, a carga parasitária foi menor nos animais tratados com as lectinas ScLL e/ou Artin M quando comparado aos animais não tratados. Também foi encontrada uma taxa de sobrevivência maior nos animais tratados com ScLL em comparação aos não tratados. Em síntese, os dados do presente estudo sugerem que os mecanismos imunomoduladores mediados pelas lectinas ScLL e Artin M podem contribuir para o controle da infecção pelo T. gondii
Avaliação do efeito da Artin M no processo de repação em mucosa mastigatória
No full textArtin M é uma lectina purificada de sementes de Artocarpus heterophyllus que, recentemente, mostrou-se capaz depromover aceleração da cicatrização de lesões por queimadura de pele ou por abrasão da córnea em ratos e coelhos. O objetivo desta tese foi avaliar os efeitos da Artin M no processo de reparação da mucosa mastigatória bucal, por meio de modelos de estudo in vivo. Primeiro estudo: Três feridas cirúrgicas circulares de 6 mm de diâmetro foram criadas na mucosa palatina de 20 cães, e divididas aleatoriamente em 3 grupos de acordo com os tratamentos: C – controle (não tratados), A - Artin M, V - veículo. Quatro animais de cada grupo foram sacrificados após 2, 4, 7, 14 e 21 dias póstratamento e suas maxilas analisadas clinicamente quanto ao padrão de cicatrização, seguido de análise histológica, imuno-histoquímica para antígeno nuclear de proliferação celular (PCNA) e atividade de mieloperoxidase. Clinicamente, o grupo A demonstrou melhor cicatrização em todos os períodos quando comparada aos outros grupos (p<0,05). A análise histológica mostrou ter havido no grupo A maior estimulação na produção de fibras colágenas, maturação do tecido de granulação e organização do epitélio. A imunolocalização de PCNA mostrou uma maior tendência na proliferação celular em lesões do grupo A principalmente nos dias iniciais (p<0,05). O influxo de neutrófilos mostrou-se estatisticamente aumentado no grupo A quando comparado aos outros grupos nos dias 2 e 4 (p<0,05). Conclui-se que a Artin M promoveu aceleração na reparação das feridas na mucosa mastigatória em cães, via recrutamento de neutrófilos e indução da proliferação celular. É bem conhecido o envolvimento de mediadores biológicos como citocinas...Artin M, lectin from Artocarpus heterophyllus seeds, has been demonstrated to stimulate recruitment and activation of neutrophil and mast cells. Furthermore, it has been shown to accelerate the process of wound healing on burn injuries and corneal epithelial lesions in rats and rabbits, respectively. The aim of this study was to evaluate the effects of Artin M on wound healing in palatal mucosa in two animal models. Study 1: Three wounds of 6 mm full thickness were surgically created in the hard palate mucosa of twenty dogs. The wounds of each animal were randomly divided into three groups according to one of the treatment assigned: C– Control (nontreated), A- Artin M gel, and V– Vehicle (carboxymethylcellulose 3% gel). Four animals per group were sacrificed at 2, 4, 7, 14 and 21 days post-surgery. Before sacrifice, wounded areas were photographed and scored for macroscopic healing evaluation. Afterwards, maxillary tissue were harvested and divided to perform histological analysis, immunohistochemical staining against Proliferating Cell Nuclear Antigen (PCNA) and measurement of myeloperoxidase activity. Clinical analysis showed that wound closure was accelerated in group A in comparison to other groups in all periods. Histological features showed enhanced reepithelization and collagen fiber formation resulting in faster maturation of granular tissue in group A compared to the other groups, by day 14. Artin M treatment significantly induced cells proliferation at day 2 and 4 (p<0.05). Neutrophils infiltration in the group A was significantly higher than in the other groups at days 2 and 4 (p<0.05). The results suggest that Artin M gel may potentially facilitate wound healing on palatal mucosa via the recruitment of neutrophils and promotion of cells proliferation. It is well known that cytokines and growth... (Complete abstract click electronic access below)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
Avaliação do efeito da Artin M no processo de repação em mucosa mastigatória
No full textArtin M é uma lectina purificada de sementes de Artocarpus heterophyllus que, recentemente, mostrou-se capaz depromover aceleração da cicatrização de lesões por queimadura de pele ou por abrasão da córnea em ratos e coelhos. O objetivo desta tese foi avaliar os efeitos da Artin M no processo de reparação da mucosa mastigatória bucal, por meio de modelos de estudo in vivo. Primeiro estudo: Três feridas cirúrgicas circulares de 6 mm de diâmetro foram criadas na mucosa palatina de 20 cães, e divididas aleatoriamente em 3 grupos de acordo com os tratamentos: C – controle (não tratados), A - Artin M, V - veículo. Quatro animais de cada grupo foram sacrificados após 2, 4, 7, 14 e 21 dias póstratamento e suas maxilas analisadas clinicamente quanto ao padrão de cicatrização, seguido de análise histológica, imuno-histoquímica para antígeno nuclear de proliferação celular (PCNA) e atividade de mieloperoxidase. Clinicamente, o grupo A demonstrou melhor cicatrização em todos os períodos quando comparada aos outros grupos (p<0,05). A análise histológica mostrou ter havido no grupo A maior estimulação na produção de fibras colágenas, maturação do tecido de granulação e organização do epitélio. A imunolocalização de PCNA mostrou uma maior tendência na proliferação celular em lesões do grupo A principalmente nos dias iniciais (p<0,05). O influxo de neutrófilos mostrou-se estatisticamente aumentado no grupo A quando comparado aos outros grupos nos dias 2 e 4 (p<0,05). Conclui-se que a Artin M promoveu aceleração na reparação das feridas na mucosa mastigatória em cães, via recrutamento de neutrófilos e indução da proliferação celular. É bem conhecido o envolvimento de mediadores biológicos como citocinas...Artin M, lectin from Artocarpus heterophyllus seeds, has been demonstrated to stimulate recruitment and activation of neutrophil and mast cells. Furthermore, it has been shown to accelerate the process of wound healing on burn injuries and corneal epithelial lesions in rats and rabbits, respectively. The aim of this study was to evaluate the effects of Artin M on wound healing in palatal mucosa in two animal models. Study 1: Three wounds of 6 mm full thickness were surgically created in the hard palate mucosa of twenty dogs. The wounds of each animal were randomly divided into three groups according to one of the treatment assigned: C– Control (nontreated), A- Artin M gel, and V– Vehicle (carboxymethylcellulose 3% gel). Four animals per group were sacrificed at 2, 4, 7, 14 and 21 days post-surgery. Before sacrifice, wounded areas were photographed and scored for macroscopic healing evaluation. Afterwards, maxillary tissue were harvested and divided to perform histological analysis, immunohistochemical staining against Proliferating Cell Nuclear Antigen (PCNA) and measurement of myeloperoxidase activity. Clinical analysis showed that wound closure was accelerated in group A in comparison to other groups in all periods. Histological features showed enhanced reepithelization and collagen fiber formation resulting in faster maturation of granular tissue in group A compared to the other groups, by day 14. Artin M treatment significantly induced cells proliferation at day 2 and 4 (p<0.05). Neutrophils infiltration in the group A was significantly higher than in the other groups at days 2 and 4 (p<0.05). The results suggest that Artin M gel may potentially facilitate wound healing on palatal mucosa via the recruitment of neutrophils and promotion of cells proliferation. It is well known that cytokines and growth... (Complete abstract click electronic access below)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
Topical application of the lectin Artin M accelerates wound healing in rat oral mucosa by enhancing TGF-β and VEGF production
No full textThe lectin Artin M has been shown to accelerate the wound-healing process. The aims of this study were to evaluate the effects of Artin M on wound healing in the palatal mucosa of rats and to investigate the effects of Artin M on transforming growth factor beta (TGF-β) and vascular endothelial growth factor (VEGF) secretion by rat gingival fibroblasts. A surgical wound was created on the palatal mucosa of 72 rats divided into three groups according to treatment: C - Control (nontreated), A - Artin M gel, and V - Vehicle. Eight animals per group were sacrificed at 3, 5, and 7 days postsurgery for histology, immunohistochemistry and determination of the levels of cytokines, and growth factors. Gingival fibroblasts were incubated with 2.5 μg/mL of Artin M for 24, 48, and 72 hours. The expression of VEGF and TGF-β was determined by enzyme-linked immunosorbent assay. Histologically, at day 7, the Artin M group showed earlier reepithelialization, milder inflammatory infiltration, and increased collagen fiber formation, resulting in faster maturation of granular tissue than in the other groups (p < 0.05). Artin M-induced cell proliferation in vivo and promoted a greater expression of TGF-β and VEGF in both experiments (p < 0.05). Artin M was effective in healing oral mucosa wounds in rats and was associated with increased TGF-β and VEGF release, cell proliferation, reepithelialization, and collagen deposition and arrangement of fibers. © 2013 by the Wound Healing Society.Department of Diagnosis and Surgery School of Dentistry UNESP - Univ. Estadual Paulista, Araraquara, Rua Humaita, 1680, São Paulo, SP 14801-903Department of Cellular and Molecular Biology School of Medicine of Ribeirao Preto University of São Paulo, São PauloDepartment of Diagnosis and Surgery School of Dentistry UNESP - Univ. Estadual Paulista, Araraquara, Rua Humaita, 1680, São Paulo, SP 14801-90
Artin M enhances TNF-α production and phagocytosis of Candida albicans mediated by dectin-1 and mannose receptors
No full textAbstractThe activities of dectin-1 and mannose receptors on phagocytosis of Candida albicans and the production of TNF-α by macrophages from mice pretreated for 3days with extract of Artocarpus intergrifolia seeds (jack extract), Artin M or jacalin were studied. Macrophages from these mice were coincubated with C. albicans CR15 (yeast), in the presence of mannose (50mM) plus mannan (100μg) or laminarin (1mg). Phagocytosis was significantly enhanced to 52% in macrophages from mice pretreated intraperitoneally for 3days with jack extract (500μg/250μl PBS). Reduction in phagocytosis from 52% to 34% (P<0.05) occurred in the presence of mannose receptor inhibitors and from 52% to 16% (P<0.01) in the presence of dectin-1 inhibitor laminarin, whereas only 20% of control macrophages phagocytosed blastoconidia. Similar results were verified for pretreatment of mice with Artin M (2.5μg/250μl PBS), but not for jacalin (25μg/250μl PBS). Macrophages from mice pretreated 3days previously with jack extract or Artin M and then coincubated for 2h with C. albicans presented a significant increase in TNF-α production, correlating with significantly less transition of yeast to filamentous forms compared to pretreatment with jacalin. These results suggest that Artin M, but not jacalin present in jack extract significantly increased TNF-α production and the activity of mannose and dectin-1 receptors
Protective effect of Artin M from extract of Artocarpus integrifolia seeds by Th1 and Th17 immune response on the course of infection by Candida albicans
No full textAbstractThe immunoregulatory effect of Artin M and jacalin from extract of Artocarpus integrifolia seeds (jack extract) against infection with Candida albicans was investigated. Swiss mice received jack extract containing 500μg protein/ml PBS intraperitoneally (i.p.) or PBS alone and after 72h were infected i.p. with C. albicans CR15 (107) and sacrificed after 30min, 2, 6, 24, and 72h. ELISA analysis revealed that in jack extract-treated mice IFN-γ was predominantly produced versus IL-10 in control mice. These results suggest that jack extract induced a protective immune response, since C. albicans clearance was complete at 72h postinfection. Jack extract presents two lectins (Artin M and jacalin) with distinct biological properties. Artin M was able to induce IL-12 production by macrophages. Also, Artin M in different concentrations, associated with jacalin or in jack extract induced both IFN-γ and IL-17 production. As a consequence, phagocytic and candidacidal activity increased significantly. Alanine aminotransferase activity (ALT) was used as parameter for damage of the liver. The activity of ALT correlated with inoculum size that increased significantly in control group, however, mice pretreated with jack extract 3days before infection presented normal ALT. Mice pretreated with jack extract that received a lethal inoculum of Candida presented 90% survival versus 20% among controls or mice pretreated with jacalin. Thus, the results suggest that Artin M by itself, associated with jacalin or present in jack extract is able to induce protective Th1 and Th17 immune responses against Candida albicans infection
Estudo da equivalência entre a lectina artin M obtida a partir da semente da jaca e a sua forma recombinante na afinidade por glicanas
No full textNo presente trabalho foi avaliada a equivalência entre as formas nativa e recombinante da lectina Artin M utilizando como ligante a peroxidase de raiz forte (HRP) por meio da técnica de microbalança a cristal de quartzo. Para tal foi preparado um biossensor por meio da imobilização da lectina, tanto nativa como recombinante, na superfície do cristal de quartzo piezelétrico. A imobilização das lectinas foi realizada por meio da construção de uma monocamada auto organizada utilizando dois alcanotióis, ácido 11-mercaptoundecanóico e o 2-mercaptoetanol. Para o acoplamento das proteínas foram utilizados N-etil-N- (dimetilaminopropil) carbodiimida (EDC) e N-hidoxisuccinimida (NHS) que formam com os grupamentos carboxílicos um intermediário reativo. Após a preparação do biossensor foi utilizado um sistema de injeção em fluxo acoplado à microbalança de cristal a quartzo para o estudo da interação lectina-glicoconjugado. Desta forma, as interações da Artin M nativa e recombinante com a glicoproteína peroxidase de raiz forte foram estudadas por meio da determinação das suas constantes de afinidade aparente e de associação cinética, sendo que foram encontrados os valores de constante de afinidade aparente (4,6 ± 0,9) x 103 e (2,6 ± 0,5) x 103 L mol -1 para as interações jArtinM-HRP e rArtinM-HRP, e os valores de constante cinética (7 ± 3) x 103 e (7 ± 2) x 103 L mol -1 para as interações jArtinM-HRP e rArtinM-HRP. Os valores das constantes de interação obtidos evidenciaram a equivalência entre ambas as formas da lectina Artin M. Neste trabalho também foi determinada a constante de associação cinética da interação entre a lectina Artin M recombinante e linhagens celulares de leucemia mielóide aguda humana (NB4, K562 e U937), no intuito de melhor entender a diferença na citotoxicidade observada da Artin M sobre estas células...In the present work was evaluated the equivalence between the native and recombinant forms of Artin M using horseradish peroxidase as ligand by means the quartz crystal microbalance technique. In this way, a biosensor was prepared immobilizing the lectin, native and recombinant forms, on piezoelectric quartz crystal surface. Lectins immobilization was realized constructing self assembled monolayers using the alkanethiols 11-mercaptoundecanoic acid and 2-mercaptoethanol. To the binding of proteins was used N-ethyl-N-(dimethylaminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS), which form with carboxylic groups a reactive intermediary. After biosensor preparation was utilized a flow injection system coupled to quartz crystal microbalance to study the lectin-glycoconjugated interaction. Thus the native Artin M and recombinant Artin M interaction with horseradish peroxidase glycoprotein were studied by determining its apparent affinity constant and association kinetic constants. The values obtained to apparent affinity constant were (4,6 ± 0,9) x 103 e (2,6 ± 0,5) x 103 L mol -1 to jArtinM-HRP e rArtinM-HRP interactions, and the values obtained to association kinetic constant were (7 ± 3) x 103 e (7 ± 2) x 103 L mol -1 to jArtinM-HRP e rArtinM-HRP interactions. These constant values evidence the equivalence between native and recombinant forms of Artin M lectin. During this work were also determined the association kinetic constant of the interaction between recombinant Artin M and leukemic lineages from human acute myeloid leukemia (NB4, K562 and U937), with the purpose of a better understanding in the different cytotoxic effect of Artin M on these cells. In this way the values of association kinetic constant obtained was (0,3 ± 0,1) x 10-7 , (0,9 ± 0,1) x 10-7 e (2,7 ± 0,3) x 10-7 mL cel -1 to the interactions between Artin M and NB4, K562 and U937, respectivelyConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
Estudo da equivalência entre a lectina artin M obtida a partir da semente da jaca e a sua forma recombinante na afinidade por glicanas
No full textNo presente trabalho foi avaliada a equivalência entre as formas nativa e recombinante da lectina Artin M utilizando como ligante a peroxidase de raiz forte (HRP) por meio da técnica de microbalança a cristal de quartzo. Para tal foi preparado um biossensor por meio da imobilização da lectina, tanto nativa como recombinante, na superfície do cristal de quartzo piezelétrico. A imobilização das lectinas foi realizada por meio da construção de uma monocamada auto organizada utilizando dois alcanotióis, ácido 11-mercaptoundecanóico e o 2-mercaptoetanol. Para o acoplamento das proteínas foram utilizados N-etil-N- (dimetilaminopropil) carbodiimida (EDC) e N-hidoxisuccinimida (NHS) que formam com os grupamentos carboxílicos um intermediário reativo. Após a preparação do biossensor foi utilizado um sistema de injeção em fluxo acoplado à microbalança de cristal a quartzo para o estudo da interação lectina-glicoconjugado. Desta forma, as interações da Artin M nativa e recombinante com a glicoproteína peroxidase de raiz forte foram estudadas por meio da determinação das suas constantes de afinidade aparente e de associação cinética, sendo que foram encontrados os valores de constante de afinidade aparente (4,6 ± 0,9) x 103 e (2,6 ± 0,5) x 103 L mol -1 para as interações jArtinM-HRP e rArtinM-HRP, e os valores de constante cinética (7 ± 3) x 103 e (7 ± 2) x 103 L mol -1 para as interações jArtinM-HRP e rArtinM-HRP. Os valores das constantes de interação obtidos evidenciaram a equivalência entre ambas as formas da lectina Artin M. Neste trabalho também foi determinada a constante de associação cinética da interação entre a lectina Artin M recombinante e linhagens celulares de leucemia mielóide aguda humana (NB4, K562 e U937), no intuito de melhor entender a diferença na citotoxicidade observada da Artin M sobre estas células...In the present work was evaluated the equivalence between the native and recombinant forms of Artin M using horseradish peroxidase as ligand by means the quartz crystal microbalance technique. In this way, a biosensor was prepared immobilizing the lectin, native and recombinant forms, on piezoelectric quartz crystal surface. Lectins immobilization was realized constructing self assembled monolayers using the alkanethiols 11-mercaptoundecanoic acid and 2-mercaptoethanol. To the binding of proteins was used N-ethyl-N-(dimethylaminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS), which form with carboxylic groups a reactive intermediary. After biosensor preparation was utilized a flow injection system coupled to quartz crystal microbalance to study the lectin-glycoconjugated interaction. Thus the native Artin M and recombinant Artin M interaction with horseradish peroxidase glycoprotein were studied by determining its apparent affinity constant and association kinetic constants. The values obtained to apparent affinity constant were (4,6 ± 0,9) x 103 e (2,6 ± 0,5) x 103 L mol -1 to jArtinM-HRP e rArtinM-HRP interactions, and the values obtained to association kinetic constant were (7 ± 3) x 103 e (7 ± 2) x 103 L mol -1 to jArtinM-HRP e rArtinM-HRP interactions. These constant values evidence the equivalence between native and recombinant forms of Artin M lectin. During this work were also determined the association kinetic constant of the interaction between recombinant Artin M and leukemic lineages from human acute myeloid leukemia (NB4, K562 and U937), with the purpose of a better understanding in the different cytotoxic effect of Artin M on these cells. In this way the values of association kinetic constant obtained was (0,3 ± 0,1) x 10-7 , (0,9 ± 0,1) x 10-7 e (2,7 ± 0,3) x 10-7 mL cel -1 to the interactions between Artin M and NB4, K562 and U937, respectivelyConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
Estudo da equivalência entre a lectina artin M obtida a partir da semente da jaca e a sua forma recombinante na afinidade por glicanas
No full textNo presente trabalho foi avaliada a equivalência entre as formas nativa e recombinante da lectina Artin M utilizando como ligante a peroxidase de raiz forte (HRP) por meio da técnica de microbalança a cristal de quartzo. Para tal foi preparado um biossensor por meio da imobilização da lectina, tanto nativa como recombinante, na superfície do cristal de quartzo piezelétrico. A imobilização das lectinas foi realizada por meio da construção de uma monocamada auto organizada utilizando dois alcanotióis, ácido 11-mercaptoundecanóico e o 2-mercaptoetanol. Para o acoplamento das proteínas foram utilizados N-etil-N- (dimetilaminopropil) carbodiimida (EDC) e N-hidoxisuccinimida (NHS) que formam com os grupamentos carboxílicos um intermediário reativo. Após a preparação do biossensor foi utilizado um sistema de injeção em fluxo acoplado à microbalança de cristal a quartzo para o estudo da interação lectina-glicoconjugado. Desta forma, as interações da Artin M nativa e recombinante com a glicoproteína peroxidase de raiz forte foram estudadas por meio da determinação das suas constantes de afinidade aparente e de associação cinética, sendo que foram encontrados os valores de constante de afinidade aparente (4,6 ± 0,9) x 103 e (2,6 ± 0,5) x 103 L mol -1 para as interações jArtinM-HRP e rArtinM-HRP, e os valores de constante cinética (7 ± 3) x 103 e (7 ± 2) x 103 L mol -1 para as interações jArtinM-HRP e rArtinM-HRP. Os valores das constantes de interação obtidos evidenciaram a equivalência entre ambas as formas da lectina Artin M. Neste trabalho também foi determinada a constante de associação cinética da interação entre a lectina Artin M recombinante e linhagens celulares de leucemia mielóide aguda humana (NB4, K562 e U937), no intuito de melhor entender a diferença na citotoxicidade observada da Artin M sobre estas células...In the present work was evaluated the equivalence between the native and recombinant forms of Artin M using horseradish peroxidase as ligand by means the quartz crystal microbalance technique. In this way, a biosensor was prepared immobilizing the lectin, native and recombinant forms, on piezoelectric quartz crystal surface. Lectins immobilization was realized constructing self assembled monolayers using the alkanethiols 11-mercaptoundecanoic acid and 2-mercaptoethanol. To the binding of proteins was used N-ethyl-N-(dimethylaminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS), which form with carboxylic groups a reactive intermediary. After biosensor preparation was utilized a flow injection system coupled to quartz crystal microbalance to study the lectin-glycoconjugated interaction. Thus the native Artin M and recombinant Artin M interaction with horseradish peroxidase glycoprotein were studied by determining its apparent affinity constant and association kinetic constants. The values obtained to apparent affinity constant were (4,6 ± 0,9) x 103 e (2,6 ± 0,5) x 103 L mol -1 to jArtinM-HRP e rArtinM-HRP interactions, and the values obtained to association kinetic constant were (7 ± 3) x 103 e (7 ± 2) x 103 L mol -1 to jArtinM-HRP e rArtinM-HRP interactions. These constant values evidence the equivalence between native and recombinant forms of Artin M lectin. During this work were also determined the association kinetic constant of the interaction between recombinant Artin M and leukemic lineages from human acute myeloid leukemia (NB4, K562 and U937), with the purpose of a better understanding in the different cytotoxic effect of Artin M on these cells. In this way the values of association kinetic constant obtained was (0,3 ± 0,1) x 10-7 , (0,9 ± 0,1) x 10-7 e (2,7 ± 0,3) x 10-7 mL cel -1 to the interactions between Artin M and NB4, K562 and U937, respectivelyConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
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