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1.
J Clin Invest ; 131(14)2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34138753

RESUMO

Glioblastoma multiforme (GBM), the most aggressive brain cancer, recurs because glioblastoma stem cells (GSCs) are resistant to all standard therapies. We showed that GSCs, but not normal astrocytes, are sensitive to lysis by healthy allogeneic natural killer (NK) cells in vitro. Mass cytometry and single-cell RNA sequencing of primary tumor samples revealed that GBM tumor-infiltrating NK cells acquired an altered phenotype associated with impaired lytic function relative to matched peripheral blood NK cells from patients with GBM or healthy donors. We attributed this immune evasion tactic to direct cell-to-cell contact between GSCs and NK cells via αv integrin-mediated TGF-ß activation. Treatment of GSC-engrafted mice with allogeneic NK cells in combination with inhibitors of integrin or TGF-ß signaling or with TGFBR2 gene-edited allogeneic NK cells prevented GSC-induced NK cell dysfunction and tumor growth. These findings reveal an important mechanism of NK cell immune evasion by GSCs and suggest the αv integrin/TGF-ß axis as a potentially useful therapeutic target in GBM.


Assuntos
Glioblastoma/imunologia , Integrinas/imunologia , Células Matadoras Naturais/imunologia , Proteínas de Neoplasias/imunologia , Células-Tronco Neoplásicas/imunologia , Fator de Crescimento Transformador beta/imunologia , Animais , Feminino , Glioblastoma/genética , Glioblastoma/patologia , Glioblastoma/terapia , Xenoenxertos , Humanos , Integrinas/genética , Células Matadoras Naturais/patologia , Masculino , Camundongos , Proteínas de Neoplasias/genética , Transplante de Neoplasias , Células-Tronco Neoplásicas/patologia , Receptor do Fator de Crescimento Transformador beta Tipo II/genética , Receptor do Fator de Crescimento Transformador beta Tipo II/imunologia , Fator de Crescimento Transformador beta/genética
2.
Biomed Microdevices ; 20(2): 49, 2018 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-29916059

RESUMO

With nearly 40% of U.S. adults obese, and childhood and adolescent rates rising, obesity and associated comorbidities are serious public health concerns with massive societal costs. Often, lifestyle interventions do not offer sufficient weight loss to improve health, requiring surgery and medications as adjunct management strategies. Here, we present a 4-month case study in which the sustained, low-dose, and constant administration of the thyroid receptor ß selective agonist GC-1 (sobetirome) from a novel nanochannel membrane implant was assessed in an obese, pre-diabetic rhesus macaque. Dramatic loss of white adipose tissue in the abdomen from 36 to 18% was observed via magnetic resonance imaging in conjunction with normalized serum insulin and glycemia, with no signs of cardiotoxicity shown. The non-human primate study highlights sustained low-dose delivery of GC-1 from our minimally invasive subcutaneous implant as a valuable approach to induce weight loss and manage obesity and comorbidities, including type 2 diabetes.


Assuntos
Acetatos/metabolismo , Sistemas de Liberação de Medicamentos/instrumentação , Nanotecnologia/instrumentação , Obesidade/metabolismo , Fenóis/metabolismo , Animais , Macaca mulatta
3.
Nanomedicine ; 13(5): 1739-1744, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28259802

RESUMO

This study demonstrated a nanochannel membrane device (NMD) for controlled and sustained release of GC-1 in rats, in the context of the treatment of metabolic syndrome. Release profiles were established in vitro both with and without 5% labrasol for over 2 months. In vivo pharmacokinetic evaluation showed effective GC-1 plasma concentrations, which resulted in significant reductions in body weight after just one week of treatment when compared to the NMD releasing vehicle only (PBS). We also provided evidence that rats treated with NMD-GC-1 present sub-active thyroids and clear differences in the morphology of the epithelium and follicles as compared to the controls, while the heart showed changes in weight. Moreover, body temperatures remained stable throughout treatment, and glucose, pancreatic islet size, and liver histology appeared similar between the treated and control groups. Prolonged constant administration of GC-1 from the NMD proved to be a valid strategy to facilitate weight loss.


Assuntos
Acetatos/farmacocinética , Nanotecnologia , Fenóis/farmacocinética , Acetatos/administração & dosagem , Animais , Peso Corporal , Fígado , Fenóis/administração & dosagem , Ratos , Ratos Endogâmicos F344
4.
Am J Physiol Heart Circ Physiol ; 294(2): H1002-9, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18083892

RESUMO

Multiple imaging modalities are employed independent of one another while managing complex cardiac arrhythmias. To combine electrical, anatomical, and functional imaging in a single catheter system, we developed a balloon catheter that carried 64 electrodes on its surface and an intracardiac echocardiography (ICE) catheter through a central lumen. The catheter system was inserted, and the balloon was inflated inside the left ventricle (LV) of eight dogs with 6-wk-old infarction, created by occlusion in the left anterior descending coronary artery. Anatomy was constructed by ICE imaging (9 MHz) through the balloon. Single-beat noncontact mapping (NCM) was performed via the multielectrode array to reconstruct unipolar endocardial electrograms during sinus rhythm. Standard contact mapping (CM) of the endocardium was also carried out for reference. Myocardial infarction in anterior LV extending from the middle to apical regions was localized both by ICE and NCM and validated by CM and pathology. The overall difference in the activation times between NCM and CM was 3 +/- 1 ms. Unipolar voltage in infarcted middle anterior LV was smaller than the voltage in normal middle inferior LV both by NCM (11 +/- 4 vs. 16 +/- 3 mV; P = 0.002) and CM (11 +/- 3 vs. 20 +/- 4 mV; P < 0.001). Unipolar voltage was also inversely related to infarct transmurality, both by NCM (r = -0.87; P = 0.005) and CM (r = -0.94; P < 0.001). The infarct area by ICE (7.7 +/- 2.9 cm(2)) was in agreement with CM (bipolar voltage, <1 mV; and area, 7.6 +/- 3.3 cm(2); r = 0.80; P = 0.016). Meanwhile, the voltage threshold that depicted the infarct area by NCM was directly related to the smallest unipolar voltage reconstructed within the infarct (r = 0.96; P < 0.001). In conclusion, combining NCM and ICE imaging in a single catheter system is feasible. The preclinical development of such an integrated system and its evaluation in experimental myocardial infarction demonstrate capabilities for single-beat mapping at multiple sites as well as the online assessment of anatomy and myocardial function.


Assuntos
Cateterismo Cardíaco/instrumentação , Coração/anatomia & histologia , Coração/fisiologia , Animais , Interpretação Estatística de Dados , Cães , Ecocardiografia , Eletrocardiografia , Eletrofisiologia , Endocárdio/anatomia & histologia , Endocárdio/diagnóstico por imagem , Endocárdio/fisiologia , Testes de Função Cardíaca , Ventrículos do Coração , Infarto do Miocárdio/fisiopatologia , Taquicardia Ventricular/fisiopatologia , Função Ventricular Esquerda/fisiologia
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