Expression of transforming growth factor-beta 1, -beta 2, and -beta 3 in human developing teeth: immunolocalization according to the odontogenesis phases.

Transforming growth factor-beta (TGF-beta) is a multifunctional growth factor that has several biological effects in vivo, including control of cell growth and differentiation, cell migration, lineage determination, motility, adhesion, apoptosis, and synthesis and degradation of extracellular matrix, and TGF-beta plays an important role in regulating tissue repair and regeneration. Our study analyzed the participation of TGF-beta 1, -beta 2, and -beta 3 in the different stages of morphogenesis and differentiation of human developing dental organ using immunohistochemistry. The maxillae and mandibles of 10 human embryos ranging from 8 to 23 weeks of gestation were employed, according to the approval of the ethical committee. Our study revealed that the TGF-beta subunits-beta 1, beta 2, and beta 3-were present in the various stages of tooth development, but the expression varied according to the differentiation stage, tissue, and TGF-beta subunit. Our results indicated that TGF-beta 1 is closely related to differentiation of enamel organ and initiation of matrix secretion, TGF-beta 2 to cellular differentiation, and TGF-beta 3 to mineral maturation matrix.

Developing human minor salivary glands: morphological parallel relation between the expression of TGF-beta isoforms and cytoskeletal markers of glandular maturation.

Morphogenesis of salivary glands involves complex coordinated events. Synchronisation between cell proliferation, polarisation and differentiation, which are dependent on epithelial-mesenchymal interactions and on the microenvironment, is a requirement. Growth factors mediate many of these orchestrated biological processes and transforming growth factor-beta (TGF-beta) appear to be relevant. Using immunohistochemistry and immunofluorescence, we have mapped the distribution of TGF-beta 1, 2 and 3 and compared it with the expression of maturation markers in human salivary glands obtained from foetuses ranging from weeks 4 to 24 of gestation. TGF-beta 1 first appeared during canalisation stage in the surrounding mesenchyme and, in the more differentiated stages, was expressed in the cytoplasm of acinar cells throughout the adult gland. TGF-beta 2 was detected since the bud stage of the salivary gland. Its expression was observed in ductal cells and increased along gland differentiation, TGF-beta 3 was detected from the canalisation stage of the salivary gland, being weakly expressed on ductal cells, and it was the only factor detected on myoepithelial cells. The data suggest that TGF-beta have a role to play in salivary gland development and differentiation.

Expression of beta-1 integrin in human developing salivary glands and its parallel relation with maturation markers: in situ hybridisation and immunofluorescence study.

BACKGROUND AND OBJECTIVE: Salivary gland development entails co-ordinated processes involving complex molecular interactions in which integrins have a fundamental role. The integrins are a family of heterodimeric transmembrane receptors comprising alpha and beta subunits that mediate intercellular and extracellular signals involved in the organisation of cells in tissues and organs during development. The beta-1 integrin in particular have been implicated in proliferation and differentiation of cells involved in the development of epithelial tissues. To understand the role of beta-1 integrin in salivary gland development we have studied its expression in human foetal tissues. DESIGN: In situ hybridisation was used to compare the expression and localisation of integrin beta-1 with differentiation markers in developing human salivary glands obtained from foetuses of 8-24 weeks gestation. RESULTS: Integrin beta-1 first appeared during bud stage in a few cells and its distribution increased as salivary gland morphogenesis progressed. This increased pattern of beta-1 integrin expression was coincident with the appearance of the differentiation markers CK14, CK low MW and smooth-muscle actin. CONCLUSIONS: The developmentally regulated expression of integrin beta-1 in association with the establishment of a mature phenotype indicated by salivary gland tissue differentiation markers is suggestive of its role in salivary gland morphogenesis.

Pleomorphic adenoma and adenoid cystic carcinoma: in vitro study of the impact of TGFbeta1 on the expression of integrins and cytoskeleton markers of cell differentiation.

Pleomorphic adenoma (PA) and adenoid cystic carcinoma (ACC) are the commonest benign and malignant salivary gland tumours respectively. Interactions between cells and extracellular matrix of PA and ACC, partially mediated by integrins, are important in their biology. The expression of integrins is regulated by numerous factors, amongst them, transforming growth factor beta1 (TGFbeta1). Our study investigated the effects of TGFbeta1 on the expression of integrin beta subunits in vitro and on the expression of cytoskeletal proteins of cells derived from PA and ACC. The expression of cytoskeletal differentiation markers and integrins was assessed using immunofluorescence. ELISA assays were employed to quantitate the expression integrins and MTT assays evaluated the mitochondrial activity of cells stimulated with TGFbeta1. PA cells showed increased expression of integrins and de novo expression of differentiation markers upon TGFbeta1 stimulation. ACC cells were less responsive to such stimulation. This may reflect important differences in the biological behaviour of benign and malignant cells.

Efficacy of an enzyme-linked immunosorbent assay as a diagnostic tool for schistosomiasis mansoni in individuals with low worm burden.

IgM-ELISA is an immunoenzymatic method useful for detection of IgM antibodies against a fraction of Schistosoma mansoni adult worm antigen (AWA) that is soluble in trichloroacetic acid (AWA-TCA). This method was applied to three groups of individuals with different clinical and epidemiological characteristics, and the results compared with those obtained by other diagnostic methods: immunofluorescence test for detection of IgM antibodies (IgM-IFT) or IgG antibodies (IgG-IFT), ELISA for detection of IgG antibodies (IgG-ELISA), and two parasitological methods, Kato-Katz and miracidium hatching. The IgM-ELISA presented a sensitivity of 98%, when the parasitologic fecal examination was defined as reference diagnostic method, and a specificity of 98 and 97.3%, respectively for the group of clinically healthy individuals and other helminth carriers. A comparative analysis between the results of IgM-ELISA and those obtained by other serologic tests showed a good degree of agreement, with Kappa indices ranging from 0.95 to 0.98. The diagnostic efficacy of 97.8%, as determined with schistosomiasis patients with low parasitic burden, suggests the excellent performance of the IgM-ELISA and its usefulness for the diagnosis of schistosomiasis when applied in low endemic areas.

Efficacy of an enzyme-linked immunosorbent assay as a diagnostic tool for schistosomiasis mansoni in individuals with low worm burden

IgM-ELISA is an immunoenzymatic method useful for detection of IgM antibodies against a fraction of Schistosoma mansoni adult worm antigen (AWA) that is soluble in trichloroacetic acid (AWA-TCA). This method was applied to three groups of individuals with different clinical and epidemiological characteristics, and the results compared with those obtained by other diagnostic methods: immunofluorescence test for detection of IgM antibodies (IgM-IFT) or IgG antibodies (IgG-IFT), ELISA for detection of IgG antibodies (IgG-ELISA), and two parasitological methods, Kato-Katz and miracidium hatching. The IgM-ELISA presented a sensitivity of 98 percent, when the parasitologic fecal examination was defined as reference diagnostic method, and a specificity of 98 and 97.3 percent, respectively for the group of clinically healthy individuals and other helminth carriers. A comparative analysis between the results of IgM-ELISA and those obtained by other serologic tests showed a good degree of agreement, with Kappa indices ranging from 0.95 to 0.98. The diagnostic efficacy of 97.8 percent, as determined with schistosomiasis patients with low parasitic burden, suggests the excellent performance of the IgM-ELISA and its usefulness for the diagnosis of schistosomiasis when applied in low endemic areas.

[IgM-ELISA for diagnosis of schistosomiasis mansoni in low endemic areas]. / ELISA-IgM para diagnóstico da esquistossomose mansoni em área de baixa endemicidade.

An immunoenzymatic method for the detection of IgM antibodies (IgM-ELISA) against a fraction of Schistosoma mansoni adult worm antigen, soluble in trichloroacetic acid (TCA-soluble fraction), was evaluated for epidemiological purposes in low endemic areas for schistosomiasis. Blood samples on filter paper were collected from a population living in the municipality of Pedro de Toledo, São Paulo State, and submitted to IgM-ELISA. The results were compared to those obtained by the IgM-immunofluorescence test (IgM-IFT) and the Kato-Katz parasitological method. Positive rates of 36.8%, 33.5%, and 1.6% were obtained respectively by the IgM-ELISA, IgM-IFT, and Kato-Katz methods. The geometric mean obtained by the parasitological method was 40.9 eggs per gram of feces (epg). The nearly perfect agreement observed between the two serological tests (Kappa index of 0,89) indicates good diagnostic performance by the evaluated test. IgM-ELISA is a potentially useful method for diagnosis of schistosomiasis in individuals with low worm burden.

ELISA-IgM para diagnóstico da esquistossomose mansoni em área de baixa endemicidade / IgM-ELISA for diagnosis of schistosomiasis mansoni in low endemic areas

Um método imunoenzimático para detecçäo de anticorpos IgM (ELISA-IgM) contra uma fraçäo do extrato total de vermes de Schistosoma mansoni, solúvel em ácido tricloro acético (fraçäo TCA-solúvel) foi avaliado para fins epidemiológicos, em área de baixa endemicidade para esquistossomose. Amostras de sangue em papel de filtro, coletadas de uma populaçäo residente no município de Pedro de Toledo, Estado de São Paulo, foram submetidas ao ELISA-IgM e os resultados, analisados comparativamente aos obtidos pela RIFI-IgM e pelo exame parasitológico de fezes Kato-Katz. Obteve-se 36,8 por cento de positividade pelo ELISA-IgM, 33,5 por cento pela RIFI-IgM e 1,6 por cento pelo Kato-Katz, que indicou uma média geométrica de 40,9 ovos por grama de fezes (opg). A concordância de resultados, quase perfeita (índice Kappa de 0,89), observada entre os dois métodos sorológicos, indica um bom desempenho diagnóstico do teste em avaliaçäo. O ELISA-IgM constitui-se em um método potencialmente útil para fins diagnósticos da esquistossomose, em indivíduos com baixa carga parasitária

Artrite reativa por esquistossomose / Reactive arthritis due to schistosomiasis

A esquistossomose é uma doença parasitária endêmica em algumas regiões do Brasil, onde na maioria as pessoas infestadas apresentam-se pouco sintomáticas e apenas uma minoria evolui com doença significativa. São muitas as síndromes clínicas relacionadas, tais como toxemia aguda, hipertensão portal, glomerulonefrite e hipertensão pulmonar, entre outras. Porém, o relato de artrite associada à mesma é raro, embora existam muitas publicações descrevendo a existência de complexos imunes relacionados à doença. Relata-se um caso em que uma paciente com diagnóstico prévio de hipertensão pulmonar secundária à esquistossomose evolui com quadro súbito de poliartrite

Decay of antibody isotypes against early developmental stages of Schistosoma mansoni after treatment of schistosomiasis patients

Em pacientes com esquistossomose, säo encontrados anticorpos contra grande número de antigenos parasitários, e aqueles contra formas evolutivas jovens do parasita demonstraram que eram eficientes marcadores imunológicos para o diagnóstico da esquistossomose. Padröes de queda de anticorpos IgM e IgG contra cercaria e esquistossomulo foram aqui estudados, comparativamente aos dos anticorpos contra verme e ovo, em pacientes esquistossomoticos após quimioterapia, abordando aspectos soroepidemiologicos. Dados obtidos no estudo de 359 amostras de soros, pertencentes a pacientes infectados por Schistosoma mansoni, individuos näo infectados e pacientes acompanhados pos-tratamento por um periodo de 12 a 15 meses...

Imunodiagnóstico da esquistossomose mansônica com baixa carga parasitária / Immunodiagnosis of schistosomiasis mansonsi with light worm burden

Presently, the schistosomiasis mansoni with low worm burden is frequent, thus immunologic assays of interest for the field diagnosis of Schistosoma mansoni light infections were evaluated here. Assays not assessed before (group I) and those requiring better validation (group II) for the screening of light infections were included in this study. In the group I, the immunofluorescence assays for the detection of IgM antibodies to worm antigens (IgM IFAw) and IgG antibodies to egg antigens (IgG IFAe) gave high levels of sensitivity, specificity, efficiency and predictive value of positive. However, the immunoenzymatic assays for the detection of IgM antibodies to worm antigens (IgM ELISAw) and to egg antigens (IgM ELISAe) had lower levels than the former assays. The assays from the group II designed mostly for the detection of IgG antibodies to same parasite antigens showed good diagnostic performance. The data obtained here contributed to evidenciate at least three category of immunoassays, and we concluded that those from the category I are suitable for seroepidemiologic purposes by keeping their diagnostic features unchanged even varying significantly the intensity of S. mansoni infection.

Evaluation of the enzyme-linked-immuno-electro-diffusion-assay (ELIEDA) for the diagnosis of Shistosoma mansoni infection with low worm burden

A tecnica de imunoprecipitacao ELIEDA (enzyme-linked-immuno-electro-difusion-assay)foi avaliada para fins diagnosticos de esquistossomose mansoni em pacientes com baixa carga parasitaria. Amostras de soros de 50 pacientes com exames de fezes positivo para S. mansoni (carga parasitaria < 600 por grama de fezes = opg) e 50 nao esquistossomoticos (30 com outras afeccoes e 20 normais) foram estudadas. Em pacientes com carga parasitaria acima de 200 opg, a sensibilidade da tecnica de ELIEDA, tanto para anticorpos com IgG como IgM , respectivamente 1,000 e 0,293, nao diferiu da observada para outras reacoes sorologicas, como a de hemoglutinacao...

Estudo sobre eventual soroconversäo motivada por reaçäo intradérmica, em esquistossomose mansônica / Eventual serologic conversion after skin testing in schistosomiasis mansoni

Em virtude de hipotética soroconversäo motivada por reaçäo intradérmica, no que concerne à esquistossomose mansônica, realizaram os autores avaliaçäo envolvendo pessoas näo infectadas. Verificaram que teste cutâneo näo promoveu positivaçäo de reaçäo sorológica de imunofluorescência indireta e, dessa, forma, consubstanciaram informe dotado de interesse prático em tarefas diagnósticas e inquéritos epidemiológicos

Pesquisa do antígeno polissacarídico do Schistosoma mansoni em soros de hamsters pela técnica de imunoeletroforese cruzada / Detection of circulating polysaccharide antigen of Schistosoma mansoni in sera of hamsters by crossed immunoelectrophoresis

A imunoeletroforese cruzada (IEC) foi utilizada para a detecçäo do antígeno polissacarídico circulante anódico (AgCA) do Schistosoma mansoni, livre e complexado, em soro de hamsters infectados. O AgCA foi também pesquisado em soros humanos de 7 pacientes na fase aguda e de 23 na fase crónica da infecçäo. Foram estabelecidas as condiçöes para isolamento e determinaçäo do AgCA complexado. A sensibilidade da técnica foi aumentada pela incorporaçäo de polietilenoglicol a 2% à agarose e realizaçäo da corrida eletroforética a 4-C. O AgCA livre foi detectado em 12 e o complexado em 30 dos 37 soros de hamsters analisados. Foi observada correlaçäo entre AgCA (livre e complexado) e carga parasitária. O AgCA näo foi detectado, nas condiçöes experimentais utilizadas, nas amostras de soro humano de 7 pacientes na fase aguda e de 23 na fase crônica da infecçäo

Treatment of patients with Schistosomiasis mansoni: a double blind clinical trial comparing praziquantel with oxamniquine

Com objetivo de se compararem a tolerabilidade e eficácia do praziquantel e oxamniquine, procedeu-se a um estudo prospectivo duplo-cego envolvendo 120 pacientes com esquistossomose intestinal ou hepatintestinal. Os pacientes foram randomizados em dois grupos. Um foi tratado com praziquantel, na dose de 55 mg/kg de peso, o outro com oxamniquine, 15 mg/kg de peso, sempre administrados em dose única por via oral. O diagnóstico e seguimento parasitológicos basearam-se no exame de fezes pelo método de Kato-Katz. Em 73 de 77 casos negativos após tratamento, executaram-se biopsias retais. Efeitos colaterais, principalmente tontura, sonolência, dores abdominais, cefaléia, náuseas e diarréia foram observados em 87% dos casos. Sua incidência, intensidade e duraçäo foram semelhantes em ambos os grupos, mas a dor abdominal foi significativamente mais freqüente após praziquantel, havendo maior tendência para tontura intensa após oxamniquine. Observou-se aumento significante de alamina-aminotransferase e gama-glutamiltransferase após oxamniquine e de bilirrubina total após praziquantel. Um total de 48 pacientes tratados com praziquantel e 46 com oxamniquine completaram os exames de controle até o sexto mês. As percentages de cura foram de 79,2% e de 84,8% respectivamente, diferença näo significativa. Os pacientes näo curados mostraram reduçäo média do número de ovos de 93,5% e de 84,1%, diferença näo significativa. Cinco pacientes retratados com praziquantel curaram-se, mas somente um de três retratados com oxamniquine. Estes resultados mostram que ambas as drogas-apesar de diferentes propriedades farmacológicas - provocam reaçöes colaterais semelhantes e apresentam eficácia terapêutica comparável