Barx1-Mediated Inhibition of Wnt Signaling in the Mouse Thoracic Foregut Controls Tracheo-Esophageal Septation and Epithelial Differentiation

Mesenchymal cells underlying the definitive endoderm in vertebrate animals play a vital role in digestive and respiratory organogenesis. Although several signaling pathways are implicated in foregut patterning and morphogenesis, and despite the clinical importance of congenital tracheal and esophageal malformations in humans, understanding of molecular mechanisms that allow a single tube to separate correctly into the trachea and esophagus is incomplete. The homoebox gene Barx1 is highly expressed in prospective stomach mesenchyme and required to specify this organ. We observed lower Barx1 expression extending contiguously from the proximal stomach domain, along the dorsal anterior foregut mesenchyme and in mesenchymal cells between the nascent esophagus and trachea. This expression pattern exactly mirrors the decline in Wnt signaling activity in late development of the adjacent dorsal foregut endoderm and medial mainstem bronchi. The hypopharynx in Barx1−/− mouse embryos is abnormally elongated and the point of esophago-tracheal separation shows marked caudal displacement, resulting in a common foregut tube that is similar to human congenital tracheo-esophageal fistula and explains neonatal lethality. Moreover, the Barx1−/− esophagus displays molecular and cytologic features of respiratory endoderm, phenocopying abnormalities observed in mouse embryos with activated ß-catenin. The zone of canonical Wnt signaling is abnormally prolonged and expanded in the proximal Barx1−/− foregut. Thus, as in the developing stomach, but distinct from the spleen, Barx1 control of thoracic foregut specification and tracheo-esophageal septation is tightly associated with down-regulation of adjacent Wnt pathway activity

Paracrine interactions between primary human macrophages and human fibroblasts enhance murine mammary gland humanization in vivo

Abstract Introduction Macrophages comprise an essential component of the mammary microenvironment necessary for normal gland development. However, there is no viable in vivo model to study their role in normal human breast function. We hypothesized that adding primary human macrophages to the murine mammary gland would enhance and provide a novel approach to examine immune-stromal cell interactions during the humanization process. Methods Primary human macrophages, in the presence or absence of ectopic estrogen stimulation, were used to humanize mouse mammary glands. Mechanisms of enhanced humanization were identified by cytokine/chemokine ELISAs, zymography, western analysis, invasion and proliferation assays; results were confirmed with immunohistological analysis. Results The combined treatment of macrophages and estrogen stimulation significantly enhanced the percentage of the total gland humanized and the engraftment/outgrowth success rate. Timecourse analysis revealed the disappearance of the human macrophages by two weeks post-injection, suggesting that the improved overall growth and invasiveness of the fibroblasts provided a larger stromal bed for epithelial cell proliferation and structure formation. Confirming their promotion of fibroblasts humanization, estrogen-stimulated macrophages significantly enhanced fibroblast proliferation and invasion in vitro, as well as significantly increased proliferating cell nuclear antigen (PCNA) positive cells in humanized glands. Cytokine/chemokine ELISAs, zymography and western analyses identified TNFα and MMP9 as potential mechanisms by which estrogen-stimulated macrophages enhanced humanization. Specific inhibitors to TNFα and MMP9 validated the effects of these molecules on fibroblast behavior in vitro, as well as by immunohistochemical analysis of humanized glands for human-specific MMP9 expression. Lastly, glands humanized with macrophages had enhanced engraftment and tumor growth compared to glands humanized with fibroblasts alone. Conclusions Herein, we demonstrate intricate immune and stromal cell paracrine interactions in a humanized in vivo model system. We confirmed our in vivo results with in vitro analyses, highlighting the value of this model to interchangeably substantiate in vitro and in vivo results. It is critical to understand the signaling networks that drive paracrine cell interactions, for tumor cells exploit these signaling mechanisms to support their growth and invasive properties. This report presents a dynamic in vivo model to study primary human immune/fibroblast/epithelial interactions and to advance our knowledge of the stromal-derived signals that promote tumorigenesis

Construção do Sistema Brasileiro de Vigilância Sanitária: argumentos para debate Construction of the Brazilian Sanitary Surveillance System: arguments to debate

Este artigo analisa a construção do Sistema Nacional de Vigilância Sanitária, um arranjo voltado à regulação e redução dos riscos sanitários decorrentes do consumo de produtos, da prestação de serviços de saúde e do ambiente no Brasil. Consideraram-se aspectos históricos, políticos, fiscais e a conjuntura atual para cotejar seu desenvolvimento com o do Sistema Nacional de Vigilância em Saúde, que tem recebido intensa cooperação internacional. O cotejamento se baseou na trajetória de seus sistemas nacionais e respectivos serviços federais, bem como nos critérios para descentralização. A análise teve como categoria central a coordenação federativa e se baseou no referencial do federalismo e das relações intergovernamentais. O contexto institucional da saúde e da vigilância sanitária apresenta forte competição política, instabilidade no projeto e provável redução da capacidade de coordenação federativa após o Pacto pela Saúde. O Sistema Nacional de Vigilância Sanitária, em razão da sua natureza de bem público e da alta externalidade de seu campo de ação, requer coordenação federativa para incremento da cooperação regional e local e também pela heterogeneidade estrutural dos municípios brasileiros.<br>This paper analyzes the Brazilian Sanitary Surveillance System as an arrangement aimed at regulating and reducing health risks associated with consumption of products, use of health services and the environment. Historical, political and tax aspects were considered and their development compared with the National Health Surveillance System, which has received strong international cooperation. The comparison was based on the trajectory of their national systems and related federal agencies, as well as on criteria adopted for decentralization. The central category of analysis is federative coordination and was based on the framework of federalism and intergovernmental relations. The institutional context of health and sanitary surveillance presents strong political competition, instability in the project and probable reduction of the ability of federal coordination after the Pact for Health. The National Sanitary Surveillance System due to its nature of public good and high externality in its field of action requires federal coordination for increasing the regional and local cooperation, also because of the structural heterogeneity of Brazilian municipalities

Integralidade, uma diretriz do SUS para a vigilância sanitária Integral care, a SUS (Brazilian Unified Health System) guideline for the sanitary surveillance

A vigilância sanitária atua através de práticas e objetos diversos e suas ações são orientadas pelos mesmos princípios e diretrizes do Sistema Único de Saúde (SUS). Propusemos uma reflexão crítica sobre as condições de interação da prática de vigilância sanitária com uma proposição constitucional do SUS, a integralidade. Realizou-se uma análise baseada na Teoria da Estruturação, de Giddens, que considera a mobilização de recursos estruturais como uma dimensão de interação social que justifica a legitimação exercida pela sanção de normas. Foram ordenadas como categorias de análise: Visa e sua inserção no SUS; o princípio da integralidade e a Visa; e entraves políticos. A vigilância sanitária vem-se organizando a partir da Anvisa e atualmente assume novas responsabilidades sanitárias, entre elas a comunicação com a sociedade e ações de promoção da saúde. A discussão na literatura para a integralidade baseia-se no aspecto assistencial. A organização dos serviços nos diferentes entes federativos é o sentido de integralidade mais incorporado pela Visa. Os entraves políticos estão na renovação institucional, na arena de conflitos de interesses, na distância entre políticas formuladas e instituídas, e nas lacunas referentes à gestão do trabalho e à insuficiência do financiamento.<br>The sanitary surveillance (Visa) performs several practices, on different objects and its actions are guided by principles and guidelines of the SUS. It was done a critical reflection on the interaction conditions of practice in Visa, with a constitutional proposition of the SUS: integral care. The analysis was based on the theory of structuration (Giddens) that considers mobilization of structural resources as dimensions of social interaction, which would justify the legitimacy exercised since the standards. Have been analyzed the following categories: Visa and its insertion within the SUS; the integral care and the Visa; and political impediments. The Visa has been organized by National Health Surveillance Agency. Nowadays it has as sanitary responsibilities, communication with society and health promotion. The proposal of the literature concerning integral care is based on the assistance issue. The organization of the services in the different federative entities is the sense of integral care most adopted by Visa. Political impediments focus on the institutional renewal, on the conflicts of interest arena, on the distance between formulated policies and established practices and gaps concerning work management and the insufficiency of financial support

Meta-analysis of the clinical and immunopathological characteristics and treatment outcomes in epidermolysis bullosa acquisita patients

Background: Epidermolysis bullosa acquisita (EBA) is an orphan autoimmune disease. Several clinical phenotypes have been described, but subepidermal blistering is characteristic of all variants. Limited data on clinical and immunopathological characteristics and treatment outcomes in EBA are available. To fill this gap, we collected this information from EBA cases, meeting current diagnostic criteria, published between 1971 and 2016. Results: We identified 1159 EBA cases. This number must be, however, interpreted with caution, as it is not possible to check for multiple reporting. The analysis of all cases indicated that EBA affects all age groups (median: 50 years, range: 1 to 94 years) at an equal gender distribution. Non-mechanobullous (non-MB) forms of EBA were observed in 55% of patients, whereas the mechanobullous variant (MB-EBA) or a combination of both variants was described in 38 or 7% of patients, respectively. Type VII collagen (COL7)-specific autoantibodies were primarily of the IgG isotype, but anti-COL7 IgA, IgM and IgE were also documented. Comparison of the 2 clinical EBA types showed a higher frequency of IgA deposits in non-MB EBA as opposed to MB EBA. Mucous membrane involvement was observed in 23% of patients, and 4.4% of cases were associated with other chronic inflammatory diseases. Of note, IgA deposits were more frequently observed in cases with mucous membrane involvement. Our analysis indicated that EBA is difficult to treat and that the choice of treatment varies widely. Chi square was applied to identify medications associated with complete remission (CR). Considering all EBA cases, intravenous immunoglobulin (IVIG, p = 0.0047) and rituximab (p = 0.0114) were associated with CR. Subgroup analysis demonstrated that no treatment was associated with CR for non-MB EBA, while IVIG (p = 0.003) was associated with CR in MB EBA. Conclusions: Within the limitations of the study, we here document the clinical and immunopathological characteristics and treatment outcomes in a large cohort of EBA patients. The observed associations of single drugs with treatment outcome may serve as a guide to develop clinical trials