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1.
Opt Express ; 30(17): 30135-30148, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36242123

RESUMO

We introduce a broadband coherent anti-Stokes Raman scattering (CARS) microscope based on a 2-MHz repetition rate ytterbium laser generating 1035-nm high-energy (≈µJ level) femtosecond pulses. These features of the driving laser allow producing broadband red-shifted Stokes pulses, covering the whole fingerprint region (400-1800 cm-1), employing supercontinuum generation in a bulk crystal. Our system reaches state-of-the-art acquisition speed (<1 ms/pixel) and unprecedented sensitivity of ≈14.1 mmol/L when detecting dimethyl sulfoxide in water. To further improve the performance of the system and to enhance the signal-to-noise ratio of the CARS spectra, we designed a convolutional neural network for spectral denoising, coupled with a post-processing pipeline to distinguish different chemical species of biological tissues.


Assuntos
Aprendizado Profundo , Análise Espectral Raman , Dimetil Sulfóxido , Água , Itérbio
2.
Hepatology ; 67(5): 1970-1985, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29105104

RESUMO

Hepatocellular carcinoma (HCC) is a frequent neoplasia and a leading cause of inflammation-related cancer mortality. Despite that most HCCs arise from persistent inflammatory conditions, pathways linking chronic inflammation to cancer development are still incompletely elucidated. We dissected the role of adaptive immunity in the Mdr2 knockout (Mdr2-/- ) mouse, a model of inflammation-associated cancer, in which ablation of adaptive immunity has been induced genetically (Rag2-/- Mdr2-/- and µMt-Mdr2-/- mice) or with in vivo treatments using lymphocyte-specific depleting antibodies (anti-CD20 or anti-CD4/CD8). We found that activated B and T lymphocytes, secreting fibrogenic tumor necrosis factor alpha (TNFα) and other proinflammatory cytokines, infiltrated liver of the Mdr2-/- mice during chronic fibrosing cholangitis. Lymphocyte ablation, in the Rag2-/- Mdr2-/- and µMt-Mdr2-/- mice, strongly suppressed hepatic stellate cell (HSC) activation and extracellular matrix deposition, enhancing HSC transition to cellular senescence. Moreover, lack of lymphocytes changed the intrahepatic metabolic/oxidative state, resulting in skewed macrophage polarization toward an anti-inflammatory M2 phenotype. Remarkably, hepatocarcinogenesis was significantly suppressed in the Rag2-/- Mdr2-/- mice, correlating with reduced TNFα/NF-κB (nuclear factor kappa B) pathway activation. Ablation of CD20+ B cells, but not of CD4+ /CD8+ T cells, in Mdr2-/- mice, promoted senescence-mediated fibrosis resolution and inhibited the protumorigenic TNFα/NF-κB pathway. Interestingly, presence of infiltrating B cells correlated with increased tumor aggressiveness and reduced disease-free survival in human HCC. CONCLUSION: Adaptive immunity sustains liver fibrosis (LF) and favors HCC growth in chronic injury, by modulating innate components of inflammation and limiting the extent of HSC senescence. Therapies designed for B-cell targeting may be an effective strategy in LF. (Hepatology 2018;67:1970-1985).


Assuntos
Linfócitos B/imunologia , Carcinogênese/imunologia , Carcinoma Hepatocelular/imunologia , Cirrose Hepática/imunologia , Neoplasias Hepáticas/imunologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Imunidade Adaptativa/imunologia , Animais , Carcinogênese/patologia , Técnicas de Cultura de Células , Senescência Celular/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Humanos , Imuno-Histoquímica , Fígado/imunologia , Fígado/patologia , Cirrose Hepática/patologia , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Membro 4 da Subfamília B de Transportadores de Cassetes de Ligação de ATP
3.
J Allergy Clin Immunol ; 142(4): 1272-1284, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29421274

RESUMO

BACKGROUND: Wiskott-Aldrich syndrome (WAS) is an X-linked immunodeficiency characterized by eczema, infections, and susceptibility to autoimmunity and malignancies. Thrombocytopenia is a constant finding, but its pathogenesis remains elusive. OBJECTIVE: To dissect the basis of the WAS platelet defect, we used a novel conditional mouse model (CoWas) lacking Wiskott-Aldrich syndrome protein (WASp) only in the megakaryocytic lineage in the presence of a normal immunologic environment, and in parallel we analyzed samples obtained from patients with WAS. METHODS: Phenotypic and functional characterization of megakaryocytes and platelets in mutant CoWas mice and patients with WAS with and without autoantibodies was performed. Platelet antigen expression was examined through a protein expression profile and cluster proteomic interaction network. Platelet immunogenicity was tested by using ELISAs and B-cell and platelet cocultures. RESULTS: CoWas mice showed increased megakaryocyte numbers and normal thrombopoiesis in vitro, but WASp-deficient platelets had short lifespan and high expression of activation markers. Proteomic analysis identified signatures compatible with defects in cytoskeletal reorganization and metabolism yet surprisingly increased antigen-processing capabilities. In addition, WASp-deficient platelets expressed high levels of surface and soluble CD40 ligand and were capable of inducing B-cell activation in vitro. WASp-deficient platelets were highly immunostimulatory in mice and triggered the generation of antibodies specific for WASp-deficient platelets, even in the context of a normal immune system. Patients with WAS also showed platelet hyperactivation and increased plasma soluble CD40 ligand levels correlating with the presence of autoantibodies. CONCLUSION: Overall, these findings suggest that intrinsic defects in WASp-deficient platelets decrease their lifespan and dysregulate immune responses, corroborating the role of platelets as modulators of inflammation and immunity.


Assuntos
Plaquetas/imunologia , Síndrome de Wiskott-Aldrich/imunologia , Adolescente , Adulto , Animais , Autoimunidade , Ligante de CD40/imunologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Inflamação/sangue , Inflamação/imunologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Contagem de Plaquetas , Síndrome de Wiskott-Aldrich/sangue , Proteína da Síndrome de Wiskott-Aldrich/genética , Proteína da Síndrome de Wiskott-Aldrich/imunologia , Adulto Jovem
4.
Hum Mol Genet ; 25(4): 740-54, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26685160

RESUMO

The congenital malformation split hand/foot (SHFM) is characterized by missing central fingers and dysmorphology or fusion of the remaining ones. Type-1 SHFM is linked to deletions/rearrangements of the DLX5-DLX6 locus and point mutations in the DLX5 gene. The ectrodactyly phenotype is reproduced in mice by the double knockout (DKO) of Dlx5 and Dlx6. During limb development, the apical ectodermal ridge (AER) is a key-signaling center responsible for early proximal-distal growth and patterning. In Dlx5;6 DKO hindlimbs, the central wedge of the AER loses multilayered organization and shows down-regulation of FGF8 and Dlx2. In search for the mechanism, we examined the non-canonical Wnt signaling, considering that Dwnt-5 is a target of distalless in Drosophila and the knockout of Wnt5, Ryk, Ror2 and Vangl2 in the mouse causes severe limb malformations. We found that in Dlx5;6 DKO limbs, the AER expresses lower levels of Wnt5a, shows scattered ß-catenin responsive cells and altered basolateral and planar cell polarity (PCP). The addition of Wnt5a to cultured embryonic limbs restored the expression of AER markers and its stratification. Conversely, the inhibition of the PCP molecule c-jun N-terminal kinase caused a loss of AER marker expression. In vitro, the addition of Wnt5a on mixed primary cultures of embryonic ectoderm and mesenchyme was able to confer re-polarization. We conclude that the Dlx-related ectrodactyly defect is associated with the loss of basoapical and PCP, due to reduced Wnt5a expression and that the restoration of the Wnt5a level is sufficient to partially reverts AER misorganization and dysmorphology.


Assuntos
Proteínas de Homeodomínio/genética , Deformidades Congênitas dos Membros/genética , Deformidades Congênitas dos Membros/patologia , Proteína Wnt-5a/farmacologia , Animais , Polaridade Celular/efeitos dos fármacos , Polaridade Celular/fisiologia , Modelos Animais de Doenças , Regulação para Baixo , Ectoderma/metabolismo , Ectoderma/patologia , Proteínas de Homeodomínio/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Deformidades Congênitas dos Membros/tratamento farmacológico , Deformidades Congênitas dos Membros/metabolismo , Mesoderma/metabolismo , Camundongos , Camundongos Knockout , Transativadores/genética , Via de Sinalização Wnt , Proteína Wnt-5a/biossíntese , Proteína Wnt-5a/deficiência , Proteína Wnt-5a/genética , beta Catenina/metabolismo
5.
J Immunol ; 186(9): 5425-34, 2011 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21441447

RESUMO

Chronic lung infections by Pseudomonas aeruginosa strains are a major cause of morbidity and mortality in cystic fibrosis (CF) patients. Although there is no clear evidence for a primary defect in the immune system of CF patients, the host is generally unable to clear P. aeruginosa from the airways. PTX3 is a soluble pattern recognition receptor that plays nonredundant roles in the innate immune response to fungi, bacteria, and viruses. In particular, PTX3 deficiency is associated with increased susceptibility to P. aeruginosa lung infection. To address the potential therapeutic effect of PTX3 in P. aeruginosa lung infection, we established persistent and progressive infections in mice with the RP73 clinical strain RP73 isolated from a CF patient and treated them with recombinant human PTX3. The results indicated that PTX3 has a potential therapeutic effect in P. aeruginosa chronic lung infection by reducing lung colonization, proinflammatory cytokine levels (CXCL1, CXCL2, CCL2, and IL-1ß), and leukocyte recruitment in the airways. In models of acute infections and in in vitro assays, the prophagocytic effect of PTX3 was maintained in C1q-deficient mice and was lost in C3- and Fc common γ-chain-deficient mice, suggesting that facilitated recognition and phagocytosis of pathogens through the interplay between complement and FcγRs are involved in the therapeutic effect mediated by PTX3. These data suggested that PTX3 is a potential therapeutic tool in chronic P. aeruginosa lung infections, such as those seen in CF patients.


Assuntos
Proteína C-Reativa/uso terapêutico , Fatores Imunológicos/uso terapêutico , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/imunologia , Infecções Respiratórias/tratamento farmacológico , Componente Amiloide P Sérico/uso terapêutico , Animais , Doença Crônica , Imunofluorescência , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Infecções por Pseudomonas/imunologia , Infecções Respiratórias/imunologia
6.
Infect Immun ; 80(1): 100-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22025515

RESUMO

Toll interleukin-1 receptor (IL-1R) 8 (TIR8), also known as single Ig IL-1 receptor (IL-R)-related molecule, or SIGIRR, is a member of the IL-1R-like family, primarily expressed by epithelial cells. Current evidence suggests that TIR8 plays a nonredundant role as a negative regulator in vivo under different inflammatory conditions that are dependent on IL-R and Toll-like receptor (TLR) activation. In the present study, we examined the role of TIR8 in innate resistance to acute lung infections caused by Pseudomonas aeruginosa, a Gram-negative pathogen responsible for life-threatening infections in immunocompromised individuals and cystic fibrosis patients. We show that Tir8 deficiency in mice was associated with increased susceptibility to acute P. aeruginosa infection, in terms of mortality and bacterial load, and to exacerbated local and systemic production of proinflammatory cytokines (gamma interferon [IFN-γ], tumor necrosis factor alpha [TNF-α], IL-1ß, and IL-6) and chemokines (CXCL1, CXCL2, and CCL2). It has been reported that host defense against P. aeruginosa acute lung infection can be improved by blocking IL-1 since exaggerated IL-1ß production may be harmful for the host in this infection. In agreement with these data, IL-1RI deficiency rescues the phenotype observed in Tir8-deficient mice: in Tir8-/- IL-1RI-/- double knockout mice we observed higher survival rates, enhanced bacterial clearance, and reduced levels of local and systemic cytokine and chemokine levels than in Tir8-deficient mice. These results suggest that TIR8 has a nonredundant effect in modulating the inflammation caused by P. aeruginosa, in particular, by negatively regulating IL-1RI signaling, which plays a major role in the pathogenesis of this infectious disease.


Assuntos
Pneumonia Bacteriana/imunologia , Infecções por Pseudomonas/imunologia , Pseudomonas aeruginosa/imunologia , Receptores de Interleucina-1/metabolismo , Animais , Carga Bacteriana , Citocinas/metabolismo , Histocitoquímica , Pulmão/microbiologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pneumonia Bacteriana/mortalidade , Infecções por Pseudomonas/mortalidade , Transdução de Sinais , Análise de Sobrevida
7.
J Hepatol ; 57(4): 813-20, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22727731

RESUMO

BACKGROUNDS & AIMS: Cholangiocarcinoma (CCA) is highly fatal because of early invasion, widespread metastasis, and lack of an effective therapy. Migration, invasion, and metastasis of CCA cells are modulated by signals received from stromal cells. The SDF-1-CXCR4 axis emerges as a pivotal regulator of migration and survival of different tumor cells. The aim of the present study was to characterize the interaction between CCA cells and human hepatic stellate cells (hHSC) focusing on the role of SDF-1. METHODS: The intrahepatic CCA cell line HuCCT-1 and primary hHSC were used for this study. RNA expression was examined by RTQ-PCR and protein expression by Western blotting. Immunofluorescence microscopy and immunohistochemistry were also employed. Migration of CCA cells was assessed using modified Boyden chambers. RESULTS: CXCR4 was clearly expressed in CCA cells of human CCA liver specimens. SDF-1 and hHSC conditioned medium (CM) promoted HuCCT-1 cell migration, which was abrogated by pre-incubation with AMD3100, a non-peptide antagonist of the CXCR4 receptor. In addition, HuCCT-1 cells silenced for CXCR4 did not migrate in presence of SDF-1. Both P-ERK and p-AKT were implicated in HuCCT-1 migration and showed a biphasic trend under stimulation of SDF-1. Finally, SDF-1 induced apoptotic rescue of HuCCT-1 cells by binding to CXCR4. CONCLUSIONS: Our study demonstrates that CCA cells migration and survival are modulated by the crosstalk between SDF-1, released by hHSC, and HuCCT-1 cells bearing CXCR4.


Assuntos
Neoplasias dos Ductos Biliares/metabolismo , Ductos Biliares Intra-Hepáticos , Comunicação Celular , Quimiocina CXCL12/metabolismo , Colangiocarcinoma/metabolismo , Células Estreladas do Fígado/metabolismo , Receptores CXCR4/metabolismo , Adulto , Idoso , Apoptose/efeitos dos fármacos , Benzilaminas , Linhagem Celular Tumoral , Quimiocina CXCL12/farmacologia , Quimiotaxia/efeitos dos fármacos , Quimiotaxia/genética , Ciclamos , Feminino , Inativação Gênica , Compostos Heterocíclicos/farmacologia , Humanos , Fígado/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fatores Inibidores da Migração de Macrófagos/farmacologia , Masculino , Pessoa de Meia-Idade , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Cultura Primária de Células , RNA/metabolismo , Receptores CXCR4/antagonistas & inibidores , Receptores CXCR4/genética
8.
Front Bioeng Biotechnol ; 10: 1042680, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36483771

RESUMO

Bone tissue features a complex microarchitecture and biomolecular composition, which determine biomechanical properties. In addition to state-of-the-art technologies, innovative optical approaches allowing the characterization of the bone in native, label-free conditions can provide new, multi-level insight into this inherently challenging tissue. Here, we exploited multimodal nonlinear optical (NLO) microscopy, including co-registered stimulated Raman scattering, two-photon excited fluorescence, and second-harmonic generation, to image entire vertebrae of murine spine sections. The quantitative nature of these nonlinear interactions allowed us to extract accurate biochemical, morphological, and topological information on the bone tissue and to highlight differences between normal and pathologic samples. Indeed, in a murine model showing bone loss, we observed increased collagen and lipid content as compared to the wild type, along with a decreased craniocaudal alignment of bone collagen fibres. We propose that NLO microscopy can be implemented in standard histopathological analysis of bone in preclinical studies, with the ambitious future perspective to introduce this technique in the clinical practice for the analysis of larger tissue sections.

9.
Commun Biol ; 5(1): 1276, 2022 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-36414721

RESUMO

We examined effects of exposing female and male mice for 33 weeks to 45% or 60% high fat diet (HFD). Males fed with either diet were more vulnerable than females, displaying higher and faster increase in body weight and more elevated cholesterol and liver enzymes levels. Higher glucose metabolism was revealed by PET in the olfactory bulbs of both sexes. However, males also displayed altered anterior cortex and cerebellum metabolism, accompanied by a more prominent brain inflammation relative to females. Although both sexes displayed reduced transcripts of neuronal and synaptic genes in anterior cortex, only males had decreased protein levels of AMPA and NMDA receptors. Oppositely, to anterior cortex, cerebellum of HFD-exposed mice displayed hypometabolism and transcriptional up-regulation of neuronal and synaptic genes. These results indicate that male brain is more susceptible to metabolic changes induced by HFD and that the anterior cortex versus cerebellum display inverse susceptibility to HFD.


Assuntos
Dieta Hiperlipídica , Obesidade , Animais , Camundongos , Masculino , Feminino , Dieta Hiperlipídica/efeitos adversos , Obesidade/metabolismo , Encéfalo/metabolismo , Peso Corporal , Neurônios/metabolismo
10.
Genesis ; 48(6): 262-373, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20333701

RESUMO

The morphogenesis of the vertebrate skull results from highly dynamic integrated processes involving the exchange of signals between the ectoderm, the endoderm, and cephalic neural crest cells (CNCCs). Before migration CNCCs are not committed to form any specific skull element, molecular signals exchanged in restricted regions of tissue interaction are crucial in providing positional identity to the CNCCs mesenchyme and activate the specific morphogenetic process of different skeletal components of the head. In particular, the endothelin-1 (Edn1)-dependent activation of Dlx5 and Dlx6 in CNCCs that colonize the first pharyngeal arch (PA1) is necessary and sufficient to specify maxillo-mandibular identity. Here, to better analyze the spatio-temporal dynamics of this process, we associate quantitative gene expression analysis with detailed examination of skeletal phenotypes resulting from combined allelic reduction of Edn1, Dlx5, and Dlx6. We show that Edn1-dependent and -independent regulatory pathways act at different developmental times in distinct regions of PA1. The Edn1-->Dlx5/6-->Hand2 pathway is already active at E9.5 during early stages of CNCCs colonization. At later stages (E10.5) the scenario is more complex: we propose a model in which PA1 is subdivided into four adjacent territories in which distinct regulations are taking place. This new developmental model may provide a conceptual framework to interpret the craniofacial malformations present in several mouse mutants and in human first arch syndromes. More in general, our findings emphasize the importance of quantitative gene expression in the fine control of morphogenetic events.


Assuntos
Endotelina-1/genética , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Proteínas de Homeodomínio/genética , Arcada Osseodentária/embriologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Humanos , Hibridização In Situ , Mandíbula/metabolismo , Camundongos , Camundongos Knockout , Fenótipo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais
11.
Mol Ther Methods Clin Dev ; 17: 369-377, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32099849

RESUMO

Many human genetic diseases are associated with gross mutations such as aneuploidies, deletions, duplications, or inversions. For these "structural" disorders, conventional gene therapy, based on viral vectors and/or on programmable nuclease-mediated homologous recombination, is still unsatisfactory. To correct such disorders, chromosome transplantation (CT), defined as the perfect substitution of an endogenous defective chromosome with an exogenous normal one, could be applied. CT re-establishes a normal diploid cell, leaving no marker of the procedure, as we have recently shown in mouse pluripotent stem cells. To prove the feasibility of the CT approach in human cells, we used human induced pluripotent stem cells (hiPSCs) reprogrammed from Lesch-Nyhan (LN) disease patients, taking advantage of their mutation in the X-linked HPRT gene, making the LN cells selectable and distinguishable from the resistant corrected normal cells. In this study, we demonstrate, for the first time, that CT is feasible in hiPSCs: the normal exogenous X chromosome was first transferred using an improved chromosome transfer system, and the extra sex chromosome was spontaneously lost. These CT cells were functionally corrected and maintained their pluripotency and differentiation capability. By inactivation of the autologous HPRT gene, CT paves the way to the correction of hiPSCs from several X-linked disorders.

12.
Bone Rep ; 12: 100242, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31938717

RESUMO

BACKGROUND: Autosomal recessive osteopetrosis is a rare skeletal disorder with increased bone density due to a failure in osteoclast bone resorption. In most cases, the defect is cell-autonomous, and >50% of patients bear mutations in the TCIRG1 gene, encoding for a subunit of the vacuolar proton pump essential for osteoclast resorptive activity. The only cure is hematopoietic stem cell transplantation, which corrects the bone pathology by allowing the formation of donor-derived functional osteoclasts. Therapeutic approaches using patient-derived cells corrected ex vivo through viral transduction or gene editing can be considered, but to date functional rescue cannot be demonstrated in vivo because a relevant animal model for xenotransplant is missing. METHODS: We generated a new mouse model, which we named NSG oc/oc, presenting severe autosomal recessive osteopetrosis owing to the Tcirg1 oc mutation, and profound immunodeficiency caused by the NSG background. We performed neonatal murine bone marrow transplantation and xenotransplantation with human CD34+ cells. RESULTS: We demonstrated that neonatal murine bone marrow transplantation rescued NSG oc/oc mice, in line with previous findings in the oc/oc parental strain and with evidence from clinical practice in humans. Importantly, we also demonstrated human cell chimerism in the bone marrow of NSG oc/oc mice transplanted with human CD34+ cells. The severity and rapid progression of the disease in the mouse model prevented amelioration of the bone pathology; nevertheless, we cannot completely exclude that minor early modifications of the bone tissue might have occurred. CONCLUSION: Our work paves the way to generating an improved xenograft model for in vivo evaluation of functional rescue of patient-derived corrected cells. Further refinement of the newly generated mouse model will allow capitalizing on it for an optimized exploitation in the path to novel cell therapies.

13.
Stem Cells Transl Med ; 8(1): 22-34, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30184340

RESUMO

Biomimetic scaffolds are extremely versatile in terms of chemical composition and physical properties, which can be defined to accomplish specific applications. One property that can be added is the production/release of bioactive soluble factors, either directly from the biomaterial, or from cells embedded within the biomaterial. We reasoned that pursuing this strategy would be appropriate to setup a cell-based therapy for RANKL-deficient autosomal recessive osteopetrosis, a very rare skeletal genetic disease in which lack of the essential osteoclastogenic factor RANKL impedes osteoclast formation. The exogenously administered RANKL cytokine is effective in achieving osteoclast formation and function in vitro and in vivo, thus, we produced murine Rankl-/- mesenchymal stromal cells (MSCs) overexpressing human soluble RANKL (hsRL) following lentiviral transduction (LVhsRL). Here, we described a three-dimensional (3D) culture system based on a magnesium-doped hydroxyapatite/collagen I (MgHA/Col) biocompatible scaffold closely reproducing bone physicochemical properties. MgHA/Col-seeded murine MSCs showed improved properties, as compared to two-dimensional (2D) culture, in terms of proliferation and hsRL production, with respect to LVhsRL-transduced cells. When implanted subcutaneously in Rankl-/- mice, these cell constructs were well tolerated, colonized by host cells, and intensely vascularized. Of note, in the bone of Rankl-/- mice that carried scaffolds with either WT or LVhsRL-transduced Rankl-/- MSCs, we specifically observed formation of TRAP+ cells, likely due to sRL released from the scaffolds into circulation. Thus, our strategy proved to have the potential to elicit an effect on the bone; further work is required to maximize these benefits and achieve improvements of the skeletal pathology in the treated Rankl-/- mice. Stem Cells Translational Medicine 2019;8:22-34.


Assuntos
Células-Tronco Mesenquimais/citologia , Osteopetrose/metabolismo , Osteopetrose/terapia , Ligante RANK/metabolismo , Biomimética/métodos , Terapia Baseada em Transplante de Células e Tecidos/métodos , Humanos , Células-Tronco Mesenquimais/fisiologia , Osteopetrose/genética , Ligante RANK/genética , Engenharia Tecidual/métodos
14.
J Bone Miner Res ; 34(11): 2133-2148, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31295380

RESUMO

Controlling oxidative stress through the activation of antioxidant pathways is crucial in bone homeostasis, and impairments of the cellular defense systems involved contribute to the pathogenesis of common skeletal diseases. In this work we focused on the dipeptidyl peptidase 3 (DPP3), a poorly investigated ubiquitous zinc-dependent exopeptidase activating the Keap1-Nrf2 antioxidant pathway. We showed Dpp3 expression in bone and, to understand its role in this compartment, we generated a Dpp3 knockout (KO) mouse model and specifically investigated the skeletal phenotype. Adult Dpp3 KO mice showed a mild growth defect, a significant increase in bone marrow cellularity, and bone loss mainly caused by increased osteoclast activity. Overall, in the mouse model, lack of DPP3 resulted in sustained oxidative stress and in alterations of bone microenvironment favoring the osteoclast compared to the osteoblast lineage. Accordingly, in vitro studies revealed that Dpp3 KO osteoclasts had an inherent increased resorptive activity and ROS production, which on the other hand made them prone to apoptosis. Moreover, absence of DPP3 augmented bone loss after estrogen withdrawal in female mice, further supporting its relevance in the framework of bone pathophysiology. Overall, we show a nonredundant role for DPP3 in the maintenance of bone homeostasis and propose that DPP3 might represent a possible new osteoimmunological player and a marker of human bone loss pathology. © 2019 American Society for Bone and Mineral Research.


Assuntos
Reabsorção Óssea , Microambiente Celular , Dipeptidil Peptidases e Tripeptidil Peptidases/deficiência , Osteoclastos , Estresse Oxidativo , Transdução de Sinais , Animais , Reabsorção Óssea/genética , Reabsorção Óssea/metabolismo , Reabsorção Óssea/patologia , Dipeptidil Peptidases e Tripeptidil Peptidases/metabolismo , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Camundongos , Camundongos Knockout , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Osteoclastos/metabolismo , Osteoclastos/patologia
15.
J Neurosci ; 27(36): 9757-68, 2007 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-17804636

RESUMO

A variety of signals governing early extension, guidance, and connectivity of olfactory receptor neuron (ORN) axons has been identified; however, little is known about axon-mesoderm and forebrain (FB)-mesoderm signals. Using Wnt-beta catenin reporter mice, we identify a novel Wnt-responsive resident cell population, located in a Frizzled7 expression domain at the surface of the embryonic FB, along the trajectory of incoming ORN axons. Organotypic slice cultures that recapitulate olfactory-associated Wnt-beta catenin activation show that the beta catenin response depends on a placode-derived signal(s). Likewise, in Dlx5-/- embryos, in which the primary connections fail to form, Wnt-beta catenin response on the surface of the FB is strongly reduced. The olfactory placode expresses a number of beta catenin-activating Wnt genes, and the Frizzled7 receptor transduces the "canonical" Wnt signal; using Wnt expression plasmids we show that Wnt5a and Wnt7b are sufficient to rescue beta catenin activation in the absence of incoming axons. Finally, blocking the canonical Wnt pathway with the exogenous application of the antagonists Dikkopf-1 or secreted-Frizzled-receptor protein-2 prevents ORN axon contact to the FB. These data reveal a novel function for Wnt signaling in the establishment of periphery-CNS olfactory connections and highlight a complex interplay between cells of different embryonic origin for ORN axon connectivity.


Assuntos
Axônios/fisiologia , Neurônios Receptores Olfatórios/fisiologia , Prosencéfalo/citologia , Prosencéfalo/fisiologia , Proteínas Wnt/fisiologia , beta Catenina/fisiologia , Animais , Embrião de Mamíferos , Receptores Frizzled/genética , Receptores Frizzled/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Genes Reporter , Mesoderma/citologia , Mesoderma/fisiologia , Camundongos , Camundongos Transgênicos , Bulbo Olfatório/citologia , Bulbo Olfatório/embriologia , Neurônios Receptores Olfatórios/ultraestrutura , Técnicas de Cultura de Órgãos , Prosencéfalo/embriologia , Transdução de Sinais/fisiologia , Proteínas Wnt/genética
16.
J Clin Invest ; 128(6): 2473-2486, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29558369

RESUMO

Adult vascular smooth muscle cells (VSMCs) dedifferentiate in response to extracellular cues such as vascular damage and inflammation. Dedifferentiated VSMCs are proliferative, migratory, less contractile, and can contribute to vascular repair as well as to cardiovascular pathologies such as intimal hyperplasia/restenosis in coronary artery and arterial aneurysm. We here demonstrate the role of ubiquitin-like containing PHD and RING finger domains 1 (UHRF1) as an epigenetic master regulator of VSMC plasticity. UHRF1 expression correlated with the development of vascular pathologies associated with modulation of noncoding RNAs, such as microRNAs. miR-145 - pivotal in regulating VSMC plasticity, which is reduced in vascular diseases - was found to control Uhrf1 mRNA translation. In turn, UHRF1 triggered VSMC proliferation, directly repressing promoters of cell-cycle inhibitor genes (including p21 and p27) and key prodifferentiation genes via the methylation of DNA and histones. Local vascular viral delivery of Uhrf1 shRNAs or Uhrf1 VSMC-specific deletion prevented intimal hyperplasia in mouse carotid artery and decreased vessel damage in a mouse model of aortic aneurysm. Our study demonstrates the fundamental role of Uhrf1 in regulating VSMC phenotype by promoting proliferation and dedifferentiation. UHRF1 targeting may hold therapeutic potential in vascular pathologies.


Assuntos
Aneurisma Aórtico/metabolismo , Artérias Carótidas/metabolismo , Epigênese Genética , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Proteínas Nucleares/metabolismo , Animais , Aneurisma Aórtico/genética , Aneurisma Aórtico/patologia , Proteínas Estimuladoras de Ligação a CCAAT , Artérias Carótidas/patologia , Diferenciação Celular/genética , Linhagem Celular , Proliferação de Células/genética , Modelos Animais de Doenças , Camundongos , Camundongos Knockout , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/patologia , Proteínas Nucleares/genética , Ubiquitina-Proteína Ligases
17.
Bone ; 114: 125-136, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29929043

RESUMO

Acrofrontofacionasal Dysostosis type 1 (AFFND1) is an extremely rare, autosomal recessive syndrome, comprising facial and skeletal abnormalities, short stature and intellectual disability. We analyzed an Indian family with two affected siblings by exome sequencing and identified a novel homozygous truncating mutation in the Neuroblastoma-Amplified Sequence (NBAS) gene in the patients' genome. Mutations in the NBAS gene have recently been associated with different phenotypes mainly involving skeletal formation, liver and cognitive development. The NBAS protein has been implicated in two key cellular processes, namely the non-sense mediated decay and the Golgi-to-Endoplasmic Reticulum retrograde traffic. Both functions were impaired in HEK293T cells overexpressing the truncated NBAS protein, as assessed by Real-Time PCR, Western blot analysis, co-immunoprecipitation, and immunofluorescence analysis. We examined the expression of NBAS protein in mouse embryos at various developmental stages by immunohistochemistry, and detected expression in developing chondrogenic and osteogenic structures of the skeleton as well as in the cortex, hippocampus and cerebellum, which is compatible with a role in bone and brain development. Functional genetics in the zebrafish model showed that depletion of endogenous z-nbas in fish embryos results in defective morphogenesis of chondrogenic cranial skeletal elements. Overall, our data point to a conserved function of NBAS in skeletal morphogenesis during development, support the hypothesis of a causative role of the mutated NBAS gene in the pathogenesis of AFFND1 and extend the spectrum of phenotypes associated with defects in this gene.


Assuntos
Disostose Mandibulofacial/diagnóstico por imagem , Disostose Mandibulofacial/genética , Mutação/genética , Proteínas de Neoplasias/genética , Irmãos , Animais , Animais Geneticamente Modificados , Feminino , Células HEK293 , Humanos , Lactente , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Peixe-Zebra
18.
Mech Dev ; 123(1): 3-16, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16330189

RESUMO

Msx and Dlx homeoproteins control the morphogenesis and organization of craniofacial skeletal structures, specifically those derived from the pharyngeal arches. In vitro Msx and Dlx proteins have opposing transcriptional properties and form heterodimeric complexes via their homeodomain with reciprocal functional repression. In this report we examine the skeletal phenotype of Msx1; Dlx5 double knock-out (DKO) mice in relationship with their expression territories during craniofacial development. Co-expression of Dlx5 and Msx1 is only observed in embryonic tissues in which these genes have independent functions, and thus direct protein interactions are unlikely to control morphogenesis of the cranium. The DKO craniofacial phenotypes indicate a complex interplay between these genes, acting independently (mandible and middle ear), synergistically (deposition of bone tissue) or converging on the same morphogenetic process (palate growth and closure). In the latter case, the absence of Dlx5 rescues in part the Msx1-dependent defects in palate growth and elevation. At the basis of this effect, our data implicate the Bmp (Bmp7, Bmp4)/Bmp antagonist (Follistatin) signal: in the Dlx5(-/-) palate changes in the expression level of Bmp7 and Follistatin counteract the reduced Bmp4 expression. These results highlight the importance of precise spatial and temporal regulation of the Bmp/Bmp antagonist system during palate closure.


Assuntos
Proteínas Morfogenéticas Ósseas/fisiologia , Ossos Faciais/embriologia , Proteínas de Homeodomínio/fisiologia , Fator de Transcrição MSX1/fisiologia , Palato/embriologia , Crânio/embriologia , Animais , Sequência de Bases , Proteína Morfogenética Óssea 7 , Proteínas Morfogenéticas Ósseas/antagonistas & inibidores , Proteínas Morfogenéticas Ósseas/genética , Anormalidades Craniofaciais/etiologia , Anormalidades Craniofaciais/genética , DNA Complementar/genética , Orelha Média/anormalidades , Orelha Média/embriologia , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/genética , Fator de Transcrição MSX1/deficiência , Fator de Transcrição MSX1/genética , Mandíbula/anormalidades , Mandíbula/embriologia , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Palato/anormalidades , Fenótipo , Transdução de Sinais , Fator de Crescimento Transformador beta/antagonistas & inibidores , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/fisiologia
19.
J Mol Histol ; 38(4): 347-58, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17588208

RESUMO

Development of the olfactory pathway requires interaction between cells and signals of different origin. Olfactory receptor neurons (ORN) in the olfactory placodes (OP) extend axons towards the forebrain (FB); with innervation taking place at a later time following degradation of the basement membrane. Cells from the OP migrate along ORN axons and differentiate into various elements, including ensheathing and Gonadotropin Releasing Hormone (GnRH)+ cells. The importance of the olfactory connection and migration is highlighted by the severe endocrine phenotype in Kallmann's patients who lack this migratory pathway. Little is known about the genetic control of intrinsic ORN properties. Inactivation of the distalless-related Dlx5 prevents connections between ORNs and FB. Using a grafting approach we show that misguidance and lack of connectivity is due to intrinsic defects in ORN neurites and migratory cells (MgC), and not to environmental factors. These data point to a cell-autonomous function of Dlx5 in providing ORN axons with their connectivity properties. Dlx5 also marks a population of early MgC that partly overlaps with the GnRH+ population. In the absence of Dlx5 MgCs of the Dlx5+ lineage migrate, associated with PSA-NCAM+ axons, but fail to reach the FB as a consequence of the lack of axonal connection and not an inability to migrate. These data suggests that Dlx5 is not required to initiate migration and differentiation of MgCs.


Assuntos
Genes Homeobox , Proteínas de Homeodomínio/genética , Condutos Olfatórios/embriologia , Animais , Axônios/metabolismo , Membrana Basal/metabolismo , Diferenciação Celular , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Proteínas de Homeodomínio/metabolismo , Camundongos , Mutação/genética , Mucosa Olfatória/citologia , Mucosa Olfatória/embriologia , Mucosa Olfatória/metabolismo , Condutos Olfatórios/citologia , Neurônios Receptores Olfatórios/metabolismo , Prosencéfalo/citologia , Prosencéfalo/metabolismo
20.
Forensic Sci Int ; 260: e1-e6, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26786144

RESUMO

Desmoid tumor is a fibroproliferative neoplasm with an intermediate malignancy and it can be localized in every bodily district: some locations are considered exceptional, like the urogenital localization. The Author point out a rare case of giant idiopathic scrotal fibromatosis that was found during an autopsy. A widower, that lived alone in poor hygienic conditions, was found dead in his house. The Judicial Authority ordered the autopsy, that was performed two days later at the Medico-Legal Section of Milan University. External examinations revealed only the considerable dimension of the scrotum (cm 24 × 41). The cause of death was fixed in a cardiac tamponade due to a natural heart laceration localized in correspondence of a transmural infarction. The toxicological exam resulted negative, while the histopathological and immunohistochemical analysis qualify the scrotal mass as a desmoids tumor. Due to the absence of predisposing conditions and of fibroproliferative infiltration in bladder and retroperitoneal space, the neoplasm was configured as an idiopathic desmoid tumor. The presented case gives the reason for the discussion concerning medico-legal aspects that are typical of rare neoplasms.


Assuntos
Fibromatose Agressiva/patologia , Neoplasias dos Genitais Masculinos/patologia , Escroto/patologia , Idoso , Patologia Legal , Humanos , Achados Incidentais , Masculino , Invasividade Neoplásica , Espaço Retroperitoneal/patologia , Bexiga Urinária/patologia
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