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1.
Nature ; 618(7966): 842-848, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37258671

RESUMO

Nonsense mutations are the underlying cause of approximately 11% of all inherited genetic diseases1. Nonsense mutations convert a sense codon that is decoded by tRNA into a premature termination codon (PTC), resulting in an abrupt termination of translation. One strategy to suppress nonsense mutations is to use natural tRNAs with altered anticodons to base-pair to the newly emerged PTC and promote translation2-7. However, tRNA-based gene therapy has not yielded an optimal combination of clinical efficacy and safety and there is presently no treatment for individuals with nonsense mutations. Here we introduce a strategy based on altering native tRNAs into  efficient suppressor tRNAs (sup-tRNAs) by individually fine-tuning their sequence to the physico-chemical properties of the amino acid that they carry. Intravenous and intratracheal lipid nanoparticle (LNP) administration of sup-tRNA in mice restored the production of functional proteins with nonsense mutations. LNP-sup-tRNA formulations caused no discernible readthrough at endogenous native stop codons, as determined by ribosome profiling. At clinically important PTCs in the cystic fibrosis transmembrane conductance regulator gene (CFTR), the sup-tRNAs re-established expression and function in cell systems and patient-derived nasal epithelia and restored airway volume homeostasis. These results provide a framework for the development of tRNA-based therapies with a high molecular safety profile and high efficacy in targeted PTC suppression.


Assuntos
Códon sem Sentido , Regulador de Condutância Transmembrana em Fibrose Cística , RNA de Transferência , Animais , Camundongos , Aminoácidos/genética , Códon sem Sentido/genética , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , RNA de Transferência/administração & dosagem , RNA de Transferência/genética , RNA de Transferência/uso terapêutico , Pareamento de Bases , Anticódon/genética , Biossíntese de Proteínas , Mucosa Nasal/metabolismo , Perfil de Ribossomos
2.
Mol Ther ; 29(6): 1970-1983, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-33823303

RESUMO

A self-transcribing and replicating RNA (STARR)-based vaccine (LUNAR-COV19) has been developed to prevent SARS-CoV-2 infection. The vaccine encodes an alphavirus-based replicon and the SARS-CoV-2 full-length spike glycoprotein. Translation of the replicon produces a replicase complex that amplifies and prolongs SARS-CoV-2 spike glycoprotein expression. A single prime vaccination in mice led to robust antibody responses, with neutralizing antibody titers increasing up to day 60. Activation of cell-mediated immunity produced a strong viral antigen-specific CD8+ T lymphocyte response. Assaying for intracellular cytokine staining for interferon (IFN)γ and interleukin-4 (IL-4)-positive CD4+ T helper (Th) lymphocytes as well as anti-spike glycoprotein immunoglobulin G (IgG)2a/IgG1 ratios supported a strong Th1-dominant immune response. Finally, single LUNAR-COV19 vaccination at both 2 µg and 10 µg doses completely protected human ACE2 transgenic mice from both mortality and even measurable infection following wild-type SARS-CoV-2 challenge. Our findings collectively suggest the potential of LUNAR-COV19 as a single-dose vaccine.


Assuntos
Anticorpos Neutralizantes/biossíntese , Anticorpos Antivirais/biossíntese , Vacinas contra COVID-19/administração & dosagem , COVID-19/prevenção & controle , SARS-CoV-2/efeitos dos fármacos , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Sintéticas/administração & dosagem , Alphavirus/genética , Alphavirus/imunologia , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/imunologia , Animais , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , COVID-19/imunologia , COVID-19/patologia , COVID-19/virologia , Vacinas contra COVID-19/biossíntese , Vacinas contra COVID-19/genética , Vacinas contra COVID-19/imunologia , Feminino , Expressão Gênica , Humanos , Imunidade Celular/efeitos dos fármacos , Imunidade Humoral/efeitos dos fármacos , Interferon gama/genética , Interferon gama/imunologia , Interleucina-4/genética , Interleucina-4/imunologia , Camundongos , Camundongos Transgênicos , Replicon/imunologia , SARS-CoV-2/imunologia , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th1/virologia , Transgenes , Resultado do Tratamento , Vacinação/métodos , Vacinas Sintéticas/biossíntese , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Vacinas de mRNA
3.
Front Oncol ; 6: 234, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27878106

RESUMO

Circulating tumor cells (CTCs) are routinely identified as cytokeratin (CK)-positive, epithelial cell adhesion molecule (EpCAM)-positive, and CD45-negative and are enriched based on EpCAM. However, there are a number of methodological challenges regarding both isolation and characterization of these rare CTCs including downregulation or absence of EpCAM in a variety of solid tumors leading to the omission of subpopulations of CTCs, difficulties in analyzing RNA and protein targets in CTCs due to the rarity of these cells, and low levels of targets and technological limitations of visualizing the targets of interest on each individual cell. Building on our previous CTC research on CD45-based negative magnetic separation and four-color fluorescent immunocytochemical (ICC) staining, RNA in situ hybridization (ISH) was applied to fluorescently target mRNA sequences corresponding to tumor-related genes at the single CTC level. Multiple categories of markers are targeted including CK, human epidermal growth factor receptor family markers, Hedgehog pathway markers, human papillomavirus markers, and protein arginine methyltransferase 5. In addition, an integrated method of RNA ISH and fluorescent ICC staining was developed to visualize CTCs on both mRNA and protein levels. The robustness of the integrated co-ICC and RNA ISH staining was demonstrated by a series of tests on representative tumor markers of different categories. The integrated staining can incorporate the advantages of both RNA ISH and fluorescent ICC staining and provide more intense signals and more specific bindings. With this integrated staining methodology, distinct staining patterns were applied in this report to facilitate the searching and characterization of rare subgroups of CTCs. These results support the existence of diverse groups of CTCs at both protein and mRNA transcript levels and provide an analytical tool for the research on CTCs of rare subgroups.

4.
Oncotarget ; 6(25): 20902-20, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26041877

RESUMO

Oral squamous cell carcinoma (OSCC) is the most common tumor of the oral cavity and has been associated with poor prognosis. Scarce prognostic markers are available for guiding treatment and/or sub-classifying patients. This study aims to identify biomarkers by searching for genes whose expression is increased or decreased during tumor progression (through T1 to T4 stages). Thirty-six samples from all tumor size stages (from T1 to T4) were analyzed using cDNA microarrays. Selected targets were analyzed by immunohistochemistry and in circulating tumor cells by immunofluorescence and Nanostring. Correlation was shown between PD-L1 and tumor size and lymph node metastasis, HOXB9 and tumor size, BLNK and perineural invasion, and between ZNF813 and perineural invasion. PD-L1 positivity was an independent prognostic factor in this cohort (p = 0.044, HH = 0.426). In CTCs from patients with locally advanced OSCC, we found a strong cytoplasmatic expression of PD-L1. PD-L1 is a ligand of PD-1 and is believed to limit T cell activity in inflammatory responses and limit autoimmune diseases. We demonstrated an important role for PD-L1 in primary tumors according to tumor size, and in disease specific survival. Therefore, we could further determine individuals with PD-L1+ CTCs, and possibly follow treatment using CTCs.


Assuntos
Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Carcinoma de Células Escamosas/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Bucais/genética , Células Neoplásicas Circulantes/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Autoimunes/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/sangue , Carcinoma de Células Escamosas/mortalidade , Estudos de Coortes , Citoplasma/metabolismo , Proteínas de Ligação a DNA/metabolismo , Feminino , Perfilação da Expressão Gênica , Proteínas de Homeodomínio/metabolismo , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/sangue , Neoplasias Bucais/mortalidade , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , Modelos de Riscos Proporcionais , Bancos de Tecidos , Resultado do Tratamento
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