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1.
Arch Environ Contam Toxicol ; 85(1): 73-91, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37452195

RESUMO

At-risk resident killer whale (Orcinus orca) populations of the northeastern Pacific, Canada, and their main prey, Chinook Salmon (Oncorhynchus tshawytscha), are exposed to a variety of contaminants including chemical elements from both natural and anthropogenic sources, which may be constraining their recovery. Concentrations of 36 chemical elements in subtidal surface sediments (1-435 m depth) collected from 98 sites along the British Columbia coast were used to characterize coast-wide patterns, and a subset of metals (mercury (Hg), cadmium (Cd), arsenic (As), nickel (Ni), copper (Cu), and lead (Pb)) were selected to assess Chinook Salmon and resident killer whale marine habitat quality. Principal component analysis (PCA) showed a dominance of Hg, antimony (Sb), Pb, Cu, and zinc (Zn) for Prince Rupert Harbour, Victoria Harbour, and Burrard Inlet, suggesting local sources. Based on the PCA, geochemical properties such as total organic carbon (TOC), acid volatile sulfide (AVS), and pH explained the spatial distribution of all elements in sediment (p < 0.001). Mercury, Cd, As, Ni, Cu, and Pb hotspots were identified along the coast of Vancouver Island, the central and north coast, in the Strait of Georgia, and Haida Gwaii. Bischof Island of Haida Gwaii and Ardmillan Bay on the central coast were most contaminated and enriched by Cd, determined by geoaccumulation index (Igeo) and enrichment factor (EF), respectively. Marine habitat quality was assessed by comparing metal concentrations to Canadian Sediment Quality Guidelines (SQGs). Chinook Salmon populations may be indirectly affected by metal toxicity (As > Cd and Cu > Ni > Hg > Pb) to lower trophic level prey species. Toxicity related impacts to benthic organisms as a result of exposure to elevated Cd and As concentrations in Northern Resident Killer Whale critical habitat and to Hg, Cd, As, Ni, Cu, and Pb concentrations in Southern Resident Killer Whale critical habitat may indirectly pose a threat to resident killer whale populations, highlighting a need for management actions to reduce risks associated with these metals.


Assuntos
Arsênio , Mercúrio , Metais Pesados , Poluentes Químicos da Água , Orca , Animais , Colúmbia Britânica , Cádmio/análise , Salmão , Chumbo/análise , Mercúrio/análise , Arsênio/análise , Níquel , Ecossistema , Metais Pesados/análise , Sedimentos Geológicos/análise , Monitoramento Ambiental , Poluentes Químicos da Água/análise
2.
Microbiol Resour Announc ; 11(11): e0092322, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36197292

RESUMO

Phages GlobiWarming and TaylorSipht are siphoviruses isolated on Arthrobacter globiformis B-2979. GlobiWarming has a 42,691 bp long genome that encodes 74 genes, whereas TaylorSipht has a 39,051 bp genome that encodes 65 genes. Both phages encode functions typical of temperate phages, with each including an immunity repressor, integrase, and excise.

3.
Environ Toxicol Chem ; 41(9): 2139-2151, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35698926

RESUMO

The northeastern Pacific northern and southern resident killer whale (Orcinus orca) populations are listed as threatened and endangered in Canada, respectively, with persistent, bioaccumulative contaminants, such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), posing threats to their recovery. Concentrations of PCBs and PBDEs in subtidal surface sediments collected from 97 sites along the British Columbia (BC) coast were used to identify their distribution and profiles, and to assess killer whale habitat quality. Victoria Harbour (VH3(site ID: 1) ) sediments exhibited the highest PCB and PBDE concentrations. For PCBs, PCB-138 was found at the highest concentration, followed by PCB-153, PCB-110, PCB-149, PCB-101, and PCB-118. For PBDEs, individual congeners were ranked as follows: BDE-209 > BDE-207 > BDE-206 > BDE-208 > BDE-47 > BDE-99. Principal component analyses (PCA) illustrated the variations in contaminant profiles, with PC1 for PCBs and PBDEs correlated with the octanol-water partition coefficient (log KOW , p < 0.003). Based on the PCA, sediment particle size, total organic carbon (TOC), and water depth at collection were other factors associated with the distribution of PBDEs, while PCB profiles were associated with TOC. Total PCB and PBDE concentrations at 100% and 34% of the sites, respectively, exceeded the recently adopted British Columbia's Ministry of Environment and Climate Change Strategy Working Sediment Quality Guidelines (PCBs 3.7 pg/g dry wt and PBDEs 1000 pg/g dry wt), considered protective of killer whales. Our findings suggest that the legacy of banned PCBs and PBDEs has the potential to constrain the recovery of killer whales as a result of their mobilization from sediments and consequent uptake by marine food webs. Environ Toxicol Chem 2022;41:2139-2151. © 2022 SETAC.


Assuntos
Bifenil Polibromatos , Bifenilos Policlorados , Poluentes Químicos da Água , Orca , Animais , Colúmbia Britânica , Ecossistema , Monitoramento Ambiental , Sedimentos Geológicos/análise , Éteres Difenil Halogenados/análise , Bifenil Polibromatos/análise , Bifenilos Policlorados/análise , Água/metabolismo , Poluentes Químicos da Água/análise , Orca/metabolismo
4.
Hosp Pediatr ; 12(6): e219-e222, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35641474

Assuntos
Hemocultura , Humanos
5.
Ann Neurol ; 91(6): 782-795, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35289960

RESUMO

OBJECTIVE: The objective of this study was to determine the impact of multiple sclerosis (MS) disease-modifying therapies (DMTs) on the development of cellular and humoral immunity to severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) infection. METHODS: Patients with MS aged 18 to 60 years were evaluated for anti-nucleocapsid and anti-Spike receptor-binding domain (RBD) antibody with electro-chemiluminescence immunoassay; antibody responses to Spike protein, RBD, N-terminal domain with multiepitope bead-based immunoassays (MBI); live virus immunofluorescence-based microneutralization assay; T-cell responses to SARS-CoV-2 Spike using TruCulture enzyme-linked immunosorbent assay (ELISA); and IL-2 and IFNγ ELISpot assays. Assay results were compared by DMT class. Spearman correlation and multivariate analyses were performed to examine associations between immunologic responses and infection severity. RESULTS: Between January 6, 2021, and July 21, 2021, 389 patients with MS were recruited (mean age 40.3 years; 74% women; 62% non-White). Most common DMTs were ocrelizumab (OCR)-40%; natalizumab -17%, Sphingosine 1-phosphate receptor (S1P) modulators -12%; and 15% untreated. One hundred seventy-seven patients (46%) had laboratory evidence of SARS-CoV-2 infection; 130 had symptomatic infection, and 47 were asymptomatic. Antibody responses were markedly attenuated in OCR compared with other groups (p ≤0.0001). T-cell responses (IFNγ) were decreased in S1P (p = 0.03), increased in natalizumab (p <0.001), and similar in other DMTs, including OCR. Cellular and humoral responses were moderately correlated in both OCR (r = 0.45, p = 0.0002) and non-OCR (r = 0.64, p <0.0001). Immune responses did not differ by race/ethnicity. Coronavirus disease 2019 (COVID-19) clinical course was mostly non-severe and similar across DMTs; 7% (9/130) were hospitalized. INTERPRETATION: DMTs had differential effects on humoral and cellular immune responses to SARS-CoV-2 infection. Immune responses did not correlate with COVID-19 clinical severity in this relatively young and nondisabled group of patients with MS. ANN NEUROL 2022;91:782-795.


Assuntos
COVID-19 , Esclerose Múltipla , Adulto , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Antivirais , Etnicidade , Feminino , Humanos , Imunidade Celular , Imunidade Humoral , Masculino , Natalizumab/uso terapêutico , SARS-CoV-2
6.
J Immunother Cancer ; 9(7)2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34230114

RESUMO

BACKGROUND: Human telomerase reverse transcriptase (hTERT) is frequently classified as a 'universal' tumor associated antigen due to its expression in a vast number of cancers. We evaluated plasmid DNA-encoded hTERT as an immunotherapy across nine cancer types. METHODS: A phase 1 clinical trial was conducted in adult patients with no evidence of disease following definitive surgery and standard therapy, who were at high risk of relapse. Plasmid DNA encoding one of two hTERT variants (INO-1400 or INO-1401) with or without plasmid DNA encoding interleukin 12 (IL-12) (INO-9012) was delivered intramuscularly concurrent with the application of the CELLECTRA constant-current electroporation device 4 times across 12 weeks. Safety assessments and immune monitoring against native (germline, non-mutated, non-plasmid matched) hTERT antigen were performed. The largest cohort of patients enrolled had pancreatic cancer, allowing for additional targeted assessments for this tumor type. RESULTS: Of the 93 enrolled patients who received at least one dose, 88 had at least one adverse event; the majority were grade 1 or 2, related to injection site. At 18 months, 54.8% (51/93) patients were disease-free, with median disease-free survival (DFS) not reached by end of study. For patients with pancreatic cancer, the median DFS was 9 months, with 41.4% of these patients remaining disease-free at 18 months. hTERT immunotherapy induced a de novo cellular immune response or enhanced pre-existing cellular responses to native hTERT in 96% (88/92) of patients with various cancer types. Treatment with INO-1400/INO-1401±INO-9012 drove hTERT-specific IFN-γ production, generated hTERT-specific CD4+ and CD8+ T cells expressing the activation marker CD38, and induced hTERT-specific activated CD8 +CTLs as defined by cells expressing perforin and granzymes. The addition of plasmid IL-12 adjuvant elicited higher magnitudes of cellular responses including IFN-γ production, activated CD4+ and CD8+ T cells, and activated CD8+CTLs. In a subset analysis of pancreatic cancer patients, the presence of immunotherapy-induced activated CD8+ T cells expressing PD-1, granzymes and perforin correlated with survival. CONCLUSIONS: Plasmid DNA-encoded hTERT/IL-12 DNA immunotherapy was well-tolerated, immune responses were noted across all tumor types, and a specific CD8+ phenotype increased by the immunotherapy was significantly correlated with survival in patients with pancreatic cancer.


Assuntos
DNA/genética , Imunoterapia/métodos , Interleucina-12/metabolismo , Neoplasias/genética , Plasmídeos/metabolismo , Telomerase/genética , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Hum Vaccin Immunother ; 16(9): 2156-2164, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32463327

RESUMO

Hepatitis B virus (HBV) causes a potentially life-threatening liver infection that frequently results in life-long chronic infection. HBV is responsible for 887,000 deaths each year, most resulting from chronic liver diseases and hepatocellular carcinoma. Presently, there are 250 million chronic HBV carriers worldwide who are at a high risk for developing cirrhosis and hepatocellular carcinoma (HCC). HCC is the most common type of liver cancer with a strong association with HBV infection. HBV transmission through blood transfusions and perinatal transfer from infected mother to child have been common routes of infection. In the present study, we describe the development of a synthetic DNA plasmid encoding an anti-HBV human monoclonal antibody specific for the common "a determinant region" of HBsAg of hepatitis B virus and demonstrate the ability of this platform at directing in vivo antibody expression. In vivo delivery of this DNA encoded monoclonal antibody (DMAb) plasmid in mice resulted in expression of human IgG over a period of one month following a single injection. Serum antibody was found to recognize the relevant conformational epitope from plasma purified native HBsAg as well as bound HBV in HepG2.2.15 cells. The serum DMAb efficiently neutralized HBV and prevented infection of HepaRG cells in vitro. Additional study of these HBV-DMAb as a possible therapy or immunoprophylaxis for HBV infection is warranted.


Assuntos
Carcinoma Hepatocelular , Hepatite B , Neoplasias Hepáticas , Animais , Anticorpos Monoclonais , DNA Viral/genética , Feminino , Hepatite B/prevenção & controle , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B/genética , Transmissão Vertical de Doenças Infecciosas , Camundongos
9.
Exp Neurol ; 309: 32-43, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30055160

RESUMO

Recovery from injury to the central nervous system (CNS) is limited in the mammalian adult. Nonetheless, some degree of spontaneous recovery occurs after partial CNS injury. Compensatory axonal growth from uninjured neurons, termed sprouting, contributes to this naturally occurring recovery process and can be modulated by molecular intervention. Extensive studies have depicted a long-held hypothesis that oligodendrocyte-derived Nogo restricts axonal sprouting and functional recovery after CNS injury. However, cell type-specific function of Nogo in compensatory sprouting, spinal axon repair or functional recovery after CNS injury has not been reported. Here we present data showing that inducible, cell type-specific deletion of Nogo from oligodendrocytes led to a ~50% increase in the compensatory sprouting of corticospinal tract (CST) axons in the cervical spinal cord after unilateral pyramidotomy in mice. In contrast to a previously proposed growth-promoting role of neuronal Nogo in the optic nerve, deleting neuronal Nogo did not significantly affect CST axon sprouting in the spinal cord. Sprouting axons were associated with the expression of synaptic marker VGLUT1 in both the oligodendrocytic Nogo deletion and control mice. However, we did not detect any functional improvement in fine motor control associated with the increased sprouting in oligodendrocytic Nogo deletion mice. These data show for the first time with genetic evidence that Nogo specifically expressed by oligodendrocytes restricts compensatory sprouting after CNS injury, supporting a longstanding but heretofore untested hypothesis. While implicating a focus on sprouting as a repair mechanism in the translational potential of targeting the myelin inhibitory pathway, our study illustrates the challenge to harness enhanced structural plasticity for functional improvement.


Assuntos
Doenças do Sistema Nervoso Central/patologia , Neurônios/metabolismo , Proteínas Nogo/metabolismo , Oligodendroglia/metabolismo , Tratos Piramidais/patologia , Fatores Etários , Animais , Axônios , Biotina/análogos & derivados , Biotina/metabolismo , Dextranos/metabolismo , Modelos Animais de Doenças , Privação de Alimentos , Lateralidade Funcional , Substância Cinzenta/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurogênese , Neurônios/patologia , Proteínas Nogo/genética , Recuperação de Função Fisiológica , Transdução Genética , Proteína Vesicular 1 de Transporte de Glutamato/metabolismo
10.
Curr Protoc Stem Cell Biol ; 46(1): e54, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29927102

RESUMO

This unit describes a protocol for acquiring and analyzing high-content super-resolution images of human stem cell nuclei for the characterization and classification of the cell differentiation paths based on distinct patterns of epigenetic mark organization. Here, we describe the cell culture, immunocytochemical labeling, super-resolution imaging parameters, and MATLAB-based quantitative image analysis approaches for monitoring human mesenchymal stem cells (hMSCs) and human induced pluripotent stem cells (hiPSCs) as the cells differentiate towards various lineages. Although this protocol uses specific cell types as examples, this approach could be easily extended to a variety of cell types and nuclear epigenetic and mechanosensitive biomarkers that are relevant to specific cell developmental scenarios. © 2018 by John Wiley & Sons, Inc.


Assuntos
Biomarcadores/metabolismo , Linhagem da Célula/genética , Epigênese Genética , Processamento de Imagem Assistida por Computador/métodos , Células-Tronco/citologia , Fosfatase Alcalina/metabolismo , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Mesenquimais/citologia , Análise de Componente Principal , Triglicerídeos/metabolismo
11.
World J Gastrointest Endosc ; 9(9): 448-455, 2017 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-28979709

RESUMO

Gastrointestinal stromal tumors (GISTs) are rare tumors of the GI tract. Surgical resection remains the mainstay of non-metastatic disease. However, the ability to provide an adequate oncologic resection using laparoscopic surgery is still an area of debate. This is a thorough review of the current literature, looking particularly at the use of laparoscopic surgery for larger GISTs and the long-term oncologic outcomes compared to the results of open surgery. Laparoscopic resections provide an adequate oncologic result for GISTs of all sizes, including those greater than 5 cm in size.

12.
Cell Mol Bioeng ; 10(5): 417-432, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28936269

RESUMO

INTRODUCTION: Human induced pluripotent stem cells (iPSCs) are a promising source of endothelial cells (iPSC-ECs) for engineering three-dimensional (3D) vascularized cardiac tissues. To mimic cardiac microvasculature, in which capillaries are oriented in parallel, we hypothesized that endothelial differentiation of iPSCs within topographically aligned 3D scaffolds would be a facile one-step approach to generate iPSC-ECs as well as induce aligned vascular organization. METHODS: Human iPSCs underwent endothelial differentiation within electrospun 3D polycaprolactone (PCL) scaffolds having either randomly oriented or parallel-aligned microfibers. Using transcriptional, protein, and endothelial functional assays, endothelial differentiation was compared between conventional two-dimensional (2D) films and 3D scaffolds having either randomly oriented or aligned microfibers. Furthermore, the role of parallel-aligned microfiber patterning on the organization of vessel-like networks was assessed. RESULTS: The cells in both the randomly oriented and aligned 3D scaffolds demonstrated an 11-fold upregulation in gene expression of the endothelial phenotypic marker, CD31, compared to cells on 2D films. This upregulation corresponded to >3-fold increase in CD31 protein expression in 3D scaffolds, compared to 2D films. Concomitantly, other endothelial phenotypic markers including CD144 and endothelial nitric oxide synthase also showed significant transcriptional upregulation in 3D scaffolds by >7-fold, compared to 2D films. Nitric oxide production, which is characteristic of endothelial function, was produced 4-fold more abundantly in 3D scaffolds, compared to on 2D PCL films. Within aligned scaffolds, the iPSC-ECs displayed parallel-aligned vascular-like networks with 70% longer branch length, compared to cells in randomly oriented scaffolds, suggesting that fiber topography modulates vascular network-like formation and patterning. CONCLUSION: Together, these results demonstrate that 3D scaffold structure promotes endothelial differentiation, compared to 2D substrates, and that aligned topographical patterning induces anisotropic vascular network organization.

13.
Sci Rep ; 7(1): 6551, 2017 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-28747756

RESUMO

Endothelial cells derived from human pluripotent stem cells are a promising cell type for enhancing angiogenesis in ischemic cardiovascular tissues. However, our understanding of microenvironmental factors that modulate the process of endothelial differentiation is limited. We examined the role of combinatorial extracellular matrix (ECM) proteins on endothelial differentiation systematically using an arrayed microscale platform. Human pluripotent stem cells were differentiated on the arrayed ECM microenvironments for 5 days. Combinatorial ECMs composed of collagen IV + heparan sulfate + laminin (CHL) or collagen IV + gelatin + heparan sulfate (CGH) demonstrated significantly higher expression of CD31, compared to single-factor ECMs. These results were corroborated by fluorescence activated cell sorting showing a 48% yield of CD31+/VE-cadherin+ cells on CHL, compared to 27% on matrigel. To elucidate the signaling mechanism, a gene expression time course revealed that VE-cadherin and FLK1 were upregulated in a dynamically similar manner as integrin subunit ß3 (>50 fold). To demonstrate the functional importance of integrin ß3 in promoting endothelial differentiation, the addition of neutralization antibody inhibited endothelial differentiation on CHL-modified dishes by >50%. These data suggest that optimal combinatorial ECMs enhance endothelial differentiation, compared to many single-factor ECMs, in part through an integrin ß3-mediated pathway.


Assuntos
Diferenciação Celular , Células Endoteliais/fisiologia , Proteínas da Matriz Extracelular/metabolismo , Células-Tronco Pluripotentes/fisiologia , Antígenos CD/análise , Caderinas/análise , Células Cultivadas , Células Endoteliais/química , Perfilação da Expressão Gênica , Humanos , Integrina beta3/biossíntese , Molécula-1 de Adesão Celular Endotelial a Plaquetas/análise , Células-Tronco Pluripotentes/química
14.
Biomater Sci ; 5(8): 1567-1578, 2017 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-28715029

RESUMO

Engineering of myocardial tissue constructs is a promising approach for treatment of coronary heart disease. To engineer myocardial tissues that better mimic the highly ordered physiological arrangement and function of native cardiomyocytes, we generated electrospun microfibrous polycaprolactone scaffolds with either randomly oriented (14 µm fiber diameter) or parallel-aligned (7 µm fiber diameter) microfiber arrangement and co-seeded the scaffolds with human induced pluripotent stem cell-derived cardiomyocytes (iCMs) and endothelial cells (iECs) for up to 12 days after iCM seeding. Here we demonstrated that aligned microfibrous scaffolds induced iCM alignment along the direction of the aligned microfibers after 2 days of iCM seeding, as well as promoted greater iCM maturation by increasing the sarcomeric length and gene expression of myosin heavy chain adult isoform (MYH7), in comparison to randomly oriented scaffolds. Furthermore, the benefit of scaffold anisotropy was evident in the significantly higher maximum contraction velocity of iCMs on the aligned scaffolds, compared to randomly oriented scaffolds, at 12 days of culture. Co-seeding of iCMs with iECs led to reduced contractility, compared to when iCMs were seeded alone. These findings demonstrate a dominant role of scaffold anisotropy in engineering cardiovascular tissues that maintain iCM organization and contractile function.


Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Células-Tronco Pluripotentes Induzidas/citologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Alicerces Teciduais/química , Anisotropia , Humanos , Porosidade , Engenharia Tecidual
15.
Sci Rep ; 7: 39406, 2017 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-28051095

RESUMO

While distinct stem cell phenotypes follow global changes in chromatin marks, single-cell chromatin technologies are unable to resolve or predict stem cell fates. We propose the first such use of optical high content nanoscopy of histone epigenetic marks (epi-marks) in stem cells to classify emergent cell states. By combining nanoscopy with epi-mark textural image informatics, we developed a novel approach, termed EDICTS (Epi-mark Descriptor Imaging of Cell Transitional States), to discern chromatin organizational changes, demarcate lineage gradations across a range of stem cell types and robustly track lineage restriction kinetics. We demonstrate the utility of EDICTS by predicting the lineage progression of stem cells cultured on biomaterial substrates with graded nanotopographies and mechanical stiffness, thus parsing the role of specific biophysical cues as sensitive epigenetic drivers. We also demonstrate the unique power of EDICTS to resolve cellular states based on epi-marks that cannot be detected via mass spectrometry based methods for quantifying the abundance of histone post-translational modifications. Overall, EDICTS represents a powerful new methodology to predict single cell lineage decisions by integrating high content super-resolution nanoscopy and imaging informatics of the nuclear organization of epi-marks.


Assuntos
Variação Biológica da População , Técnicas Citológicas/métodos , Epigênese Genética , Processamento de Imagem Assistida por Computador/métodos , Células-Tronco Mesenquimais/classificação , Células-Tronco Mesenquimais/citologia , Imagem Óptica/métodos , Núcleo Celular/química , Cromatina/química , Humanos
16.
Acta Biomater ; 41: 17-26, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27262741

RESUMO

UNLABELLED: Engineering of three-dimensional (3D) tissues is a promising approach for restoring diseased or dysfunctional myocardium with a functional replacement. However, a major bottleneck in this field is the lack of efficient vascularization strategies, because tissue constructs produced in vitro require a constant flow of oxygen and nutrients to maintain viability and functionality. Compared to angiogenic cell therapy and growth factor treatment, bioengineering approaches such as spatial micropatterning, integration of sacrificial materials, tissue decellularization, and 3D bioprinting enable the generation of more precisely controllable neovessel formation. In this review, we summarize the state-of-the-art approaches to develop 3D tissue engineered constructs with vasculature, and demonstrate how some of these techniques have been applied towards regenerative medicine for treatment of heart failure. STATEMENT OF SIGNIFICANCE: Tissue engineering is a promising approach to replace or restore dysfunctional tissues/organs, but a major bottleneck in realizing its potential is the challenge of creating scalable 3D tissues. Since most 3D engineered tissues require a constant supply of nutrients, it is necessary to integrate functional vasculature within the tissues in order to facilitate the transport of nutrients. To address these needs, researchers are employing biomaterial engineering and design strategies to foster vessel formation within 3D tissues. This review highlights the state-of-the-art bioengineering tools and technologies to create vascularized 3D tissues for clinical applications in regenerative medicine, highlighting the application of these technologies to engineer vascularized cardiac patches for treatment of heart failure.


Assuntos
Neovascularização Fisiológica , Medicina Regenerativa/métodos , Engenharia Tecidual/métodos , Animais , Materiais Biocompatíveis/farmacologia , Humanos , Impressão Tridimensional
17.
Am J Physiol Heart Circ Physiol ; 310(4): H455-65, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26683902

RESUMO

Stem cell therapy is a promising approach for the treatment of tissue ischemia associated with myocardial infarction and peripheral arterial disease. Stem and progenitor cells derived from bone marrow or from pluripotent stem cells have shown therapeutic benefit in boosting angiogenesis as well as restoring tissue function. Notably, adult stem and progenitor cells including mononuclear cells, endothelial progenitor cells, and mesenchymal stem cells have progressed into clinical trials and have shown positive benefits. In this review, we overview the major classes of stem and progenitor cells, including pluripotent stem cells, and summarize the state of the art in applying these cell types for treating myocardial infarction and peripheral arterial disease.


Assuntos
Isquemia/terapia , Isquemia Miocárdica/terapia , Neovascularização Fisiológica , Transplante de Células-Tronco/métodos , Animais , Humanos
18.
Immunology ; 142(4): 594-602, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24527796

RESUMO

VGX-1027 [(S,R)-3-phenyl-4,5-dihydro-5-isoxasole acetic acid] is a small molecule compound with immunomodulatory properties, which favourably influences the development of immuno-inflammatory and autoimmune diseases in different animal models such as type 1 diabetes mellitus, pleurisy, rheumatoid arthritis and inflammatory bowel disease. However, the precise mechanism of action of VGX-1027 remains to be ascertained. With this aim, we have studied the immunomodulatory effects of VGX-1027 in vitro, using a genome-wide oligonucleotide microarray approach, and in vivo, using the NZB/NZW F1 model of systemic lupus erythematosus. Microarray data revealed that the administration of VGX-1027 profoundly affected the immune response to exogenous antigens, by modulating the expression of genes that are primarily involved in antigen processing and presentation as well as genes that regulate immune activation. When administered in vivo VGX-1027 ameliorated the course of the disease in the NZB/NZW F1 mice, which correlated with higher per cent survival and improved clinical and histopathological signs. The data presented herein support the theory that VGX-1027 modulates immunity, probably by inhibiting inflammatory antigen presentation and so limiting immune cell expansion.


Assuntos
Acetatos/farmacologia , Fatores Imunológicos/farmacologia , Lipopolissacarídeos/toxicidade , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Oxazóis/farmacologia , Receptor 4 Toll-Like/imunologia , Animais , Modelos Animais de Doenças , Feminino , Humanos , Lúpus Eritematoso Sistêmico/induzido quimicamente , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/patologia , Masculino , Camundongos
19.
Vaccines (Basel) ; 2(2): 196-215, 2014 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-26344618

RESUMO

DNA vaccine-induced immunity can be enhanced by the co-delivery of synthetic gene-encoding molecular adjuvants. Many of these adjuvants have included cytokines, chemokines or co-stimulatory molecules that have been demonstrated to enhance vaccine-induced immunity by increasing the magnitude or type of immune responses and/or protective efficacy. In this way, through the use of adjuvants, immune responses can be highly customizable and functionally tailored for optimal efficacy against pathogen specific (i.e., infectious agent) or non-pathogen (i.e., cancer) antigens. In the novel study presented here, we examined the use of cellular transcription factors as molecular adjuvants. Specifically the co-delivery of (a) RelA, a subunit of the NF-κB transcription complex or (b) T-bet, a Th1-specific T box transcription factor, along with a prototypical DNA vaccine expressing HIV-1 proteins was evaluated. As well, all of the vaccines and adjuvants were administered to mice using in vivo electroporation (EP), a technology demonstrated to dramatically increase plasmid DNA transfection and subsequent transgene expression with concomitant enhancement of vaccine induced immune responses. As such, this study demonstrated that co-delivery of either adjuvant resulted in enhanced T and B cell responses, specifically characterized by increased T cell numbers, IFN-γ production, as well as enhanced antibody responses. This study demonstrates the use of cellular transcription factors as adjuvants for enhancing DNA vaccine-induced immunity.

20.
Methods Mol Biol ; 1052: 41-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23737097

RESUMO

Current methods to characterize cell-biomaterial interactions are population-based and rely on imaging or biochemical analysis of end-point biological markers. The analysis of stem cells in cultures is further challenged by the heterogeneous nature and divergent fates of stem cells, especially in complex, engineered microenvironments. Here, we describe a high content imaging-based platform capable of identifying cell subpopulations based on cell phenotype-specific morphological descriptors. This method can be utilized to identify microenvironment-responsive morphological descriptors, which can be used to parse cells from a heterogeneous cell population based on emergent phenotypes at the single-cell level and has been successfully deployed to forecast long-term cell lineage fates and screen regenerative phenotype-prescriptive biomaterials.


Assuntos
Células-Tronco Mesenquimais/citologia , Imagem Óptica/métodos , Células-Tronco Pluripotentes/citologia , Materiais Biocompatíveis/química , Biomarcadores , Células da Medula Óssea , Técnicas de Cultura de Células , Diferenciação Celular , Células Cultivadas , Humanos
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