A New Method for Rapidly Generating Gene-Targeting Vectors by Engineering BACs Through Homologous Recombination in Bacteria

Generating knockout mice is still an expensive and highly time-consuming process. Target construct generation, the first labor-intensive step in this process, requires the manipulation of large fragments of DNA and numerous, and often cumbersome, cloning steps. Here we show the development of a rapid approach for generating targeting constructs that capitalizes on efficient homologous recombination between linear DNA fragments and circular plasmids in Escherichia coli (“recombineering”), the availability of bacterial artificial chromosomes (BACs), and the accessibility of the sequence of the mouse genome. Employing recombineering, we demonstrate with only 1–2 template plasmids, short homologies (40–50bp) between donor and target DNA, and one subcloning step that we can efficiently manipulate BACs in situ to generate a complicated targeting vector. This procedure avoids the need to construct or screen genomic libraries and permits the generation of most standard, conditional, or knock-in targeting vectors, often within two weeks

Laminin-Mediated interactions in Thymocyte Migration and Development

Submitted by sandra infurna ([email protected]) on 2016-04-14T16:08:30Z No. of bitstreams: 1 wilson3_savino_etl_IOC_2015.pdf: 889837 bytes, checksum: 4fa4cdafd4c3d852c3f398c218aa99d2 (MD5)Approved for entry into archive by sandra infurna ([email protected]) on 2016-04-14T16:20:34Z (GMT) No. of bitstreams: 1 wilson3_savino_etl_IOC_2015.pdf: 889837 bytes, checksum: 4fa4cdafd4c3d852c3f398c218aa99d2 (MD5)Made available in DSpace on 2016-04-14T16:20:34Z (GMT). No. of bitstreams: 1 wilson3_savino_etl_IOC_2015.pdf: 889837 bytes, checksum: 4fa4cdafd4c3d852c3f398c218aa99d2 (MD5) Previous issue date: 2015Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ, Brasil.Intrathymic T-cell differentiation is a key process for the development and maintenance of cell-mediated immunity, and occurs concomitantly to highly regulated migratory events. We have proposed a multivectorial model for describing intrathymic thymocyte migration. One of the individual vectors comprises interactions mediated by laminins (LMs), a heterotrimeric protein family of the extracellular matrix. Several LMs are expressed in the thymus, being produced by microenvironmental cells, particularly thymic epithelial cells (TECs). Also, thymocytes and epithelial cells express integrin-type LM receptors. Functionally, it has been reported that the dy/dy mutant mouse (lacking the LM isoform 211) exhibits defective thymocyte differentiation. Several data show haptotactic effects of LMs upon thymocytes, as well as their adhesion on TECs; both effects being prevented by anti-LM or anti-LM receptor antibodies. Interestingly, LM synergizes with chemokines to enhance thymocyte migration, whereas classe-3 semaphorins and B ephrins, which exhibit chemorepulsive effects in the thymus, downregulate LM-mediated migratory responses of thymocytes. More recently, we showed that knocking down the ITGA6 gene (which encodes the α6 integrin chain of LM receptors) in human TECs modulates a large number of cell migration-related genes and results in changes of adhesion pattern of thymocytes onto the thymic epithelium. Overall, LM-mediated interactions can be placed at the cross-road of the multivectorial process of thymocyte migration, with a direct influence per se, as well as by modulating other molecular interactions associated with the intrathymic-trafficking events

Neuroendocrine Control of Macrophage Development and Function

Submitted by Sandra Infurna ([email protected]) on 2019-02-10T19:28:55Z No. of bitstreams: 1 arnondias_juberg_etal_IOC_2018.pdf: 2042436 bytes, checksum: e62a73d671b9925b43cab1a45f36a80a (MD5)Approved for entry into archive by Sandra Infurna ([email protected]) on 2019-02-10T19:40:25Z (GMT) No. of bitstreams: 1 arnondias_juberg_etal_IOC_2018.pdf: 2042436 bytes, checksum: e62a73d671b9925b43cab1a45f36a80a (MD5)Made available in DSpace on 2019-02-10T19:40:25Z (GMT). No. of bitstreams: 1 arnondias_juberg_etal_IOC_2018.pdf: 2042436 bytes, checksum: e62a73d671b9925b43cab1a45f36a80a (MD5) Previous issue date: 2018Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ, Brasil / Instituto Nacional de Ciência e Tecnologia em Neuroimunomodulação. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ, Brasil / Instituto Nacional de Ciência e Tecnologia em Neuroimunomodulação. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ, Brasil / Instituto Nacional de Ciência e Tecnologia em Neuroimunomodulação. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ, Brasil / Instituto Nacional de Ciência e Tecnologia em Neuroimunomodulação. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ, Brasil / Instituto Nacional de Ciência e Tecnologia em Neuroimunomodulação. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ, Brasil / Instituto Nacional de Ciência e Tecnologia em Neuroimunomodulação. Rio de Janeiro, RJ, Brasil.Macrophages carry out numerous physiological activities that are essential for both systemic and local homeostasis, as well as innate and adaptive immune responses. Their biology is intricately regulated by hormones, neuropeptides, and neurotransmitters, establishing distinct neuroendocrine axes. The control is pleiotropic, including maturation of bone marrow-derived myeloid precursors, cell differentiation into functional subpopulations, cytotoxic activity, phagocytosis, production of inflammatory mediators, antigen presentation, and activation of effector lymphocytes. Additionally, neuroendocrine components modulate macrophage ability to influence tumor growth and to prevent the spreading of infective agents. Interestingly, macrophage-derived factors enhance glucocorticoid production through the stimulation of the hypothalamic–pituitary–adrenal axis. These bidirectional effects highlight a tightly controlled balance between neuroendocrine stimuli and macrophage function in the development of innate and adaptive immune responses. Herein, we discuss how components of neuroendocrine axes impact on macrophage development and function and may ultimately influence inflammation, tissue repair, infection, or cancer progression. The knowledge of the crosstalk between macrophages and endocrine or brain-derived components may contribute to improve and create new approaches with clinical relevance in homeostatic or pathological conditions

Fibronectin modulates thymocyte-thymic epithelial cell interactions following Trypanosoma cruzi infection

Developing thymocytes interact with thymic epithelial cells (TECs) through cell-cell interactions, TEC-derived secretory moieties and extracellular matrix (ECM)-mediated interactions. These physiological interactions are crucial for normal thymocyte differentiation, but can be disrupted in pathological situations. Indeed, there is severe thymic atrophy in animals acutely infected with Trypanosoma cruzi due to CD4+CD8+ thymocyte depletion secondary to caspase-mediated apoptosis, together with changes in ECM deposition and thymocyte migration. We studied an in vitro model of TEC infection by T. cruzi and found that infected TEC cultures show a reduced number of cells, which was likely associated with decreased proliferative capacity, but not with increased cell death, as demonstrated by bromodeoxyuridine and annexin-V labelling. The infected TEC cultures exhibited increased expression of fibronectin (FN), laminin (LM) and type IV collagen. Importantly, treatment with FN increased the relative number of infected cells, whereas treatment with anti-FN or anti-LM antibodies resulted in lower infection rates. Consistent with these data, we observed increased thymocyte adhesion to infected TEC cultures. Overall, these results suggest that ECM molecules, particularly FN, facilitate infection of the thymic epithelium and that the consequent enhancement of ECM expression might be associated with changes in TEC-thymocyte interactions

Comparison of the editing patterns and editing efficiencies of TALEN and CRISPR-Cas9 when targeting the human CCR5 gene

<div><p>Abstract The human C-C chemokine receptor type-5 (CCR5) is the major transmembrane co-receptor that mediates HIV-1 entry into target CD4+ cells. Gene therapy to knock-out the CCR5 gene has shown encouraging results in providing a functional cure for HIV-1 infection. In gene therapy strategies, the initial region of the CCR5 gene is a hotspot for producing functional gene knock-out. Such target gene editing can be done using programmable endonucleases such as transcription activator-like effector nucleases (TALEN) or clustered regularly interspaced short palindromic repeats (CRISPR-Cas9). These two gene editing approaches are the most modern and effective tools for precise gene modification. However, little is known of potential differences in the efficiencies of TALEN and CRISPR-Cas9 for editing the beginning of the CCR5 gene. To examine which of these two methods is best for gene therapy, we compared the patterns and amount of editing at the beginning of the CCR5 gene using TALEN and CRISPR-Cas9 followed by DNA sequencing. This comparison revealed that CRISPR-Cas9 mediated the sorting of cells that contained 4.8 times more gene editing than TALEN+ transfected cells.</p></div

Comparison of the editing patterns and editing efficiencies of TALEN and CRISPR-Cas9 when targeting the human CCR5 gene

<div><p>Abstract The human C-C chemokine receptor type-5 (CCR5) is the major transmembrane co-receptor that mediates HIV-1 entry into target CD4+ cells. Gene therapy to knock-out the CCR5 gene has shown encouraging results in providing a functional cure for HIV-1 infection. In gene therapy strategies, the initial region of the CCR5 gene is a hotspot for producing functional gene knock-out. Such target gene editing can be done using programmable endonucleases such as transcription activator-like effector nucleases (TALEN) or clustered regularly interspaced short palindromic repeats (CRISPR-Cas9). These two gene editing approaches are the most modern and effective tools for precise gene modification. However, little is known of potential differences in the efficiencies of TALEN and CRISPR-Cas9 for editing the beginning of the CCR5 gene. To examine which of these two methods is best for gene therapy, we compared the patterns and amount of editing at the beginning of the CCR5 gene using TALEN and CRISPR-Cas9 followed by DNA sequencing. This comparison revealed that CRISPR-Cas9 mediated the sorting of cells that contained 4.8 times more gene editing than TALEN+ transfected cells.</p></div

New strategies for acute liver failure: focus on xenotransplantation therapy

Submitted by Janaína Nascimento ([email protected]) on 2019-03-13T14:42:11Z No. of bitstreams: 1 ve_Alves_Luiz_etal_INI_2010.pdf: 6199860 bytes, checksum: 4d883283eb60e10f14086d3f8957930f (MD5)Approved for entry into archive by Janaína Nascimento ([email protected]) on 2019-03-18T13:03:06Z (GMT) No. of bitstreams: 1 ve_Alves_Luiz_etal_INI_2010.pdf: 6199860 bytes, checksum: 4d883283eb60e10f14086d3f8957930f (MD5)Made available in DSpace on 2019-03-18T13:03:06Z (GMT). No. of bitstreams: 1 ve_Alves_Luiz_etal_INI_2010.pdf: 6199860 bytes, checksum: 4d883283eb60e10f14086d3f8957930f (MD5) Previous issue date: 2010Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Comunicação Celular. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Comunicação Celular. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Comunicação Celular. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Comunicação Celular. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Comunicação Celular. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Inovações em Terapias, Ensino e Bioprodutos. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto de Pesquisa Evandro Chagas. Rio de Janeiro, RJ, Brasil.Acute liver failure (ALF) has a poor prognosis and, despite intensive care support, reported average survival is only 10-40%. The most common causes responsible for ALF are viral hepatitis (mainly hepatitis A and B) and acetaminophen poisoning. Hepatic transplantation is the only appropriate treatment for patients with unlikely survival with supportive care alone. Survival rates after transplantation can be as high as 80-90% at the end of the first year. However, there is a shortage of donors and is not uncommon that no appropriate donor matches with the patient in time to avoid death. Therefore, new technologies are in constant development, including blood purification therapies as plasmapheresis, hemodiafiltration, and bioartificial liver support. However, they are still of limited efficacy or at an experimental level, and new strategies are welcome. Accordingly, cell transplantation has been developed to serve as a possible bridge to spontaneous recovery or liver transplantation. Xenotransplant of adult hepatocytes offers an interesting alternative. Moreover, the development of transgenic pigs with less immunogenic cells associated with new immunosuppressor strategies has allowed the development of this area. This article reviews some of the newly developed techniques, with focus on xenotransplant of adult hepatocytes, which might have clinical benefits as future treatment for ALF

Image_1_Neuroendocrine Control of Macrophage Development and Function.TIF

<p>Macrophages carry out numerous physiological activities that are essential for both systemic and local homeostasis, as well as innate and adaptive immune responses. Their biology is intricately regulated by hormones, neuropeptides, and neurotransmitters, establishing distinct neuroendocrine axes. The control is pleiotropic, including maturation of bone marrow-derived myeloid precursors, cell differentiation into functional subpopulations, cytotoxic activity, phagocytosis, production of inflammatory mediators, antigen presentation, and activation of effector lymphocytes. Additionally, neuroendocrine components modulate macrophage ability to influence tumor growth and to prevent the spreading of infective agents. Interestingly, macrophage-derived factors enhance glucocorticoid production through the stimulation of the hypothalamic–pituitary–adrenal axis. These bidirectional effects highlight a tightly controlled balance between neuroendocrine stimuli and macrophage function in the development of innate and adaptive immune responses. Herein, we discuss how components of neuroendocrine axes impact on macrophage development and function and may ultimately influence inflammation, tissue repair, infection, or cancer progression. The knowledge of the crosstalk between macrophages and endocrine or brain-derived components may contribute to improve and create new approaches with clinical relevance in homeostatic or pathological conditions.</p

Lack of Galectin-3 Disrupts Thymus Homeostasis in Association to Increase of Local and Systemic Glucocorticoid Levels and Steroidogenic Machinery

Submitted by Sandra Infurna ([email protected]) on 2018-10-09T13:15:20Z No. of bitstreams: 1 edneaO_abreu_etal_IOC_2018.pdf: 4005349 bytes, checksum: 6bab5839acd772e48032b95e4145e894 (MD5)Approved for entry into archive by Sandra Infurna ([email protected]) on 2018-10-09T13:26:40Z (GMT) No. of bitstreams: 1 edneaO_abreu_etal_IOC_2018.pdf: 4005349 bytes, checksum: 6bab5839acd772e48032b95e4145e894 (MD5)Made available in DSpace on 2018-10-09T13:26:40Z (GMT). No. of bitstreams: 1 edneaO_abreu_etal_IOC_2018.pdf: 4005349 bytes, checksum: 6bab5839acd772e48032b95e4145e894 (MD5) Previous issue date: 2018Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ. Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ. Brasil / Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Inflamação. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Inflamação. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ. Brasil / Instituto Nacional de Ciência e Tecnologia em Neuroimunomodulação. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Inflamação. Rio de Janeiro, RJ, Brasil / Instituto Nacional de Ciência e Tecnologia em Neuroimunomodulação. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Pesquisa sobre o Timo. Rio de Janeiro, RJ. Brasil / Instituto Nacional de Ciência e Tecnologia em Neuroimunomodulação. Rio de Janeiro, RJ, Brasil.Maintenance of thymus homeostasis is a delicate interplay involving hormones, neurotransmitters and local microenvironmental proteins, as well as saccharides, acting on both thymocytes and stromal cells. Disturbances in these interactions may lead to alterations on thymocyte development. We previously showed that galectin-3, a β-galactoside-binding protein, is constitutively expressed in the thymus, interacting with extracellular matrix glycoproteins and acting as a de-adhesion molecule, thus modulating thymocyte-stromal cell interactions. In this work, we aimed to investigate the participation of galectin-3 in the maintenance of thymus homeostasis, including hormonal-mediated circuits. For that, we used genetically engineered galectin-3-deficient mice. We observed that the thymus of galectin-3-deficient mice was reduced in mass and cellularity compared to wild-type controls; however, the proportions of different thymocyte subpopulations defined by CD4/CD8 expression were not changed. Considering the CD4-CD8- double-negative (DN) subpopulation, an accumulation of the most immature (DN1) stage was observed. Additionally, the proliferative capacity of thymocytes was decreased in all thymocyte subsets, whereas the percentage of apoptosis was increased, especially in the CD4+CD8+ double-positive thymocytes. As glucocorticoid hormones are known to be involved in thymus homeostasis, we evaluated serum and intrathymic corticosterone levels by radioimmunoassay, and the expression of steroidogenic machinery using real-time PCR. We detected a significant increase in corticosterone levels in both serum and thymus samples of galectin-3-deficient mice, as compared to age-matched controls. This was paralleled by an increase of gene transcription of the steroidogenic enzymes, steroidogenic acute regulatory protein (Star) and Cyp11b1 in thymus, 11β-Hydroxysteroid Dehydrogenase (Hsd11b1) in the adrenal, and Cyp11a1 in both glands. In conclusion, our findings show that the absence of galectin-3 subverts mouse thymus homeostasis by a mechanism likely associated to intrathymic and systemic stress-related endocrine circuitries, affecting thymocyte number, proliferation and apoptosis