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1.
Opt Express ; 32(6): 8506-8519, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571108

RESUMO

In this paper, a 1 × 2 photonic switch is designed based on a silicon-on-insulator (SOI) platform combined with the phase change material (PCM), Sb2S3, assisted by the direct binary search (DBS) algorithm. The designed photonic switch exhibits an impressive operating bandwidth ranging from 1450 to 1650 nm. The device has an insertion loss (IL) from 0.44 dB to 0.70 dB (of less than 0.7 dB) and cross talk (CT) from -26 dB to -20 dB (of less than -20 dB) over an operating bandwidth of 200 nm, especially an IL of 0.52 dB and CT of -24 dB at 1550 nm. Notably, the device is highly compact, with footprints of merely 3 × 4 µm2. Furthermore, we have extended the device's functionality for multifunctional operation in the C-band that can serve as both a 1 × 2 photonic switch and a 3 dB photonic power splitter. In the photonic switch mode, the device demonstrates an IL of 0.7 dB and a CT of -13.5 dB. In addition, when operating as a 3 dB photonic power splitter, the IL is less than 0.5 dB.

2.
Pathol Res Pract ; 255: 155220, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38432050

RESUMO

BACKGROUND: This study investigates the role of IGFBP3-mediated m6A modification in regulating the miR-23a-3p/SMAD5 axis and its impact on fracture healing, aiming to provide insights into potential therapeutic targets. METHODS: Utilizing fracture-related datasets, we identified m6A modification-related mRNA and predicted miR-23a-3p as a regulator of SMAD5. We established a mouse fracture healing model and conducted experiments, including Micro-CT, RT-qPCR, Alizarin Red staining, and Alkaline phosphatase (ALP) staining, to assess gene expression and osteogenic differentiation. RESULTS: IGFBP3 emerged as a crucial player in fracture healing, stabilizing miR-23a-3p through m6A modification, leading to SMAD5 downregulation. This, in turn, inhibited osteogenic differentiation and delayed fracture healing. Inhibition of IGFBP3 partially reversed through SMAD5 inhibition, restoring osteogenic differentiation and fracture healing in vivo. CONCLUSION: The IGFBP3/miR-23a-3p/SMAD5 axis plays a pivotal role in fracture healing, highlighting the relevance of m6A modification. IGFBP3's role in stabilizing miR-23a-3p expression through m6A modification offers a potential therapeutic target for enhancing fracture healing outcomes.


Assuntos
Adenina , Consolidação da Fratura , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina , Animais , Camundongos , Adenina/análogos & derivados , Diferenciação Celular , Modelos Animais de Doenças , Regulação para Baixo , MicroRNAs/genética , MicroRNAs/metabolismo , Osteogênese/fisiologia , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo
3.
Nanomaterials (Basel) ; 13(18)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37764544

RESUMO

The on-chip nano-integration of large-scale optical phased arrays (OPAs) is a development trend. However, the current scale of integrated OPAs is not large because of the limitations imposed by the lateral dimensions of beam-splitting structures. Here, we propose an ultra-compact and broadband OPA beam-splitting scheme with a nano-inverse design. We employed a staged design to obtain a T-branch with a wavelength bandwidth of 500 nm (1300-1800 nm) and an insertion loss of -0.2 dB. Owing to the high scalability and width-preserving characteristics, the cascaded T-branch configuration can significantly reduce the lateral dimensions of an OPA, offering a potential solution for the on-chip integration of a large-scale OPA. Based on three-dimensional finite-difference time-domain (3D FDTD) simulations, we demonstrated a 1 × 16 OPA beam-splitter structure composed entirely of inverse-designed elements with a lateral dimension of only 27.3 µm. Additionally, based on the constructed grating couplers, we simulated the range of the diffraction angle θ for the OPA, which varied by 0.6°-41.6° within the wavelength range of 1370-1600 nm.

4.
Mol Ther Nucleic Acids ; 17: 615-625, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31394430

RESUMO

Currently, the most effective and durable therapeutic option for HIV-1 infection is combination antiretroviral therapy (cART). Although cART is powerful and can delay viral evolution of drug resistance for decades, it is associated with limitations, including an inability to eradicate the virus and a potential for adverse effects. Therefore, it is imperative to discover new HIV therapeutic modalities. In this study, we designed, characterized, and evaluated the in vitro potency of 2'-deoxy-2'-fluoroarabinonucleotide (FANA) modified antisense oligonucleotides (ASOs) targeting highly conserved regions in the HIV-1 genome. Carrier-free cellular internalization of FANA ASOs resulted in strong suppression of HIV-1 replication in HIV-1-infected human primary cells. In vitro mechanistic studies suggested that the inhibitory effect of FANA ASOs can be attributed to RNase H1 activation and steric hindrance of dimerization. Using 5'-RACE PCR and sequencing analysis, we confirmed the presence of human RNase H1-mediated target RNA cleavage products in cells treated with FANA ASOs. We observed no overt cytotoxicity or immune responses upon FANA ASO treatment. Together, our results strongly suggest that FANA ASOs hold great promise for antiretroviral therapy. The dual ability of FANA ASOs to target RNA by recruiting RNase H1 and/or sterically blocking RNA dimerization further enhances their therapeutic potential.

5.
J Vis Exp ; (148)2019 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-31305524

RESUMO

The HIV-1 infectious cycle requires viral protein interactions with host factors to facilitate viral replication, packaging, and release. The infectious cycle further requires the formation of viral/host protein complexes with HIV-1 RNA to regulate the splicing and enable nucleocytoplasmic transport. The HIV-1 Rev protein accomplishes the nuclear export of HIV-1 mRNAs through multimerization with intronic cis-acting targets - the Rev response element (RRE). A nucleolar localization signal (NoLS) exists within the COOH-terminus of the Rev arginine-rich motif (ARM), allowing the accumulation of Rev/RRE complexes in the nucleolus. Nucleolar factors are speculated to support the HIV-1 infectious cycle through various other functions in addition to mediating mRNA-independent nuclear export and splicing. We describe an immunoprecipitation method of wild-type (WT) Rev in comparison to Rev nucleolar mutations (deletion and single-point Rev-NoLS mutations) in the presence of HIV-1 replication for mass spectrometry. Nucleolar factors implicated in the nucleocytoplasmic transport (nucleophosmin B23 and nucleolin C23), as well as cellular splicing factors, lose interaction with Rev in the presence of Rev-NoLS mutations. Various other nucleolar factors, such as snoRNA C/D box 58, are identified to lose interaction with Rev mutations, yet their function in the HIV-1 replication cycle remain unknown. The results presented here demonstrate the use of this approach for the identification of viral/host nucleolar factors that maintain the HIV-1 infectious cycle. The concepts used in this approach are applicable to other viral and disease models requiring the characterization of understudied pathways.


Assuntos
Nucléolo Celular/metabolismo , HIV-1/fisiologia , Imunoprecipitação , Espectrometria de Massas , Replicação Viral/fisiologia , Produtos do Gene rev do Vírus da Imunodeficiência Humana/metabolismo , HIV-1/genética , Células HeLa , Humanos , Mutação/genética , Sinais Direcionadores de Proteínas/genética , RNA Viral/genética
6.
Mol Ther ; 27(5): 999-1016, 2019 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-30852139

RESUMO

Excessive or inappropriate inflammatory responses can cause serious and even fatal diseases. The CCAAT/enhancer-binding protein alpha (CEBPA) gene encodes C/EBPα, a transcription factor that plays a fundamental role in controlling maturation of the myeloid lineage and is also expressed during the late phase of inflammatory responses when signs of inflammation are decreasing. MTL-CEBPA, a small activating RNA targeting for upregulation of C/EBPα, is currently being evaluated in a phase 1b trial for treatment of hepatocellular carcinoma. After dosing, subjects had reduced levels of pro-inflammatory cytokines, and we therefore hypothesized that MTL-CEBPA has anti-inflammatory potential. The current study was conducted to determine the effects of C/EBPα saRNA - CEBPA-51 - on inflammation in vitro and in vivo after endotoxin challenge. CEBPA-51 led to increased expression of the C/EBPα gene and inhibition of pro-inflammatory cytokines in THP-1 monocytes previously stimulated by E. coli-derived lipopolysaccharide (LPS). Treatment with MTL-CEBPA in an LPS-challenged humanized mouse model upregulated C/EBPα mRNA, increased neutrophils, and attenuated production of several key pro-inflammatory cytokines, including TNF-α, IL-6, IL-1ß, and IFN-γ. In addition, a Luminex analysis of mouse serum revealed that MTL-CEBPA reduced pro-inflammatory cytokines and increased the anti-inflammatory cytokine IL-10. Collectively, the data support further investigation of MTL-CEBPA in acute and chronic inflammatory diseases where this mechanism has pathogenic importance.


Assuntos
Proteínas Estimuladoras de Ligação a CCAAT/genética , Inflamação/terapia , Monócitos/efeitos dos fármacos , RNA/genética , Animais , Anti-Inflamatórios/farmacologia , Proteínas Estimuladoras de Ligação a CCAAT/antagonistas & inibidores , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/patologia , Interleucina-10/genética , Interleucina-1beta/genética , Lipopolissacarídeos/toxicidade , Camundongos , Monócitos/metabolismo , RNA/farmacologia , RNA Mensageiro/genética , Fator de Necrose Tumoral alfa/genética
7.
J Vis Exp ; (143)2019 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-30663638

RESUMO

Ethical regulations and technical challenges for research in human pathology, immunology, and therapeutic development have placed small animal models in high demand. With a close genetic and behavioral resemblance to humans, small animals such as the mouse are good candidates for human disease models, through which human-like symptoms and responses can be recapitulated. Further, the mouse genetic background can be altered to accommodate diverse demands. The NOD/SCID/IL2rγnull (NSG) mouse is one of the most widely used immunocompromised mouse strains; it allows engraftment with human hematopoietic stem cells and/or human tissues and the subsequent development of a functional human immune system. This is a critical milestone in understanding the prognosis and pathophysiology of human-specific diseases such as HIV/AIDS and aiding the search for a cure. Herein, we report a detailed protocol for generating a humanized NSG mouse model (hu-NSG) by hematopoietic stem cell transplantation into a radiation-conditioned neonatal NSG mouse. The hu-NSG mouse model shows multi-lineage development of transplanted human stem cells and susceptibility to HIV-1 viral infection. It also recapitulates key biological characteristics in response to combinatorial antiretroviral therapy (cART).


Assuntos
Infecções por HIV/imunologia , Replicação Viral/imunologia , Animais , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID
8.
AIDS Res Hum Retroviruses ; 34(11): 961-981, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29804468

RESUMO

Combination antiretroviral therapy fails in complete suppression of HIV-1 due to drug resistance and persistent latency. Novel therapeutic intervention requires knowledge of intracellular pathways responsible for viral replication, specifically those untargeted by antiretroviral drugs. An understudied phenomenon is the nucleolar localization of Rev phosphoprotein, which completes nucleocytoplasmic transport of unspliced/partially spliced HIV mRNA through multimerization with intronic cis-acting targets-the Rev-response element (RRE). Rev contains a nucleolar localization signal (NoLS) comprising the COOH terminus of the arginine-rich motif for accumulation within nucleoli-speculated as the interaction ground for Rev with cellular proteins mediating mRNA-independent nuclear export and splicing. Functionality of Rev nucleolar access during HIV-1 production and infection was investigated in the context of deletion and single-point mutations within Rev-NoLS. Mutations induced upon Rev-NoLS are hypothesized to inactivate the HIV-1 infectious cycle. HIV-1HXB2 replication ceased with Rev mutations lacking nucleolar access due to loss or replacement of multiple arginine residues. Rev mutations missing single arginine residues remained strictly nucleolar in pattern and participated in proviral production, however, with reduced efficiency. Viral RNA packaging also decreased in efficiency after expression of nucleolar-localizing mutations. These results were observed during propagation of variant HIV-1NL4-3 containing nucleolar-localizing mutations within the viral backbone (M4, M5, and M6). Lentiviral particles produced with Rev single-point mutations were transducible at extremely low frequency. Similarly, HIV-1NL4-3 Rev-NoLS variants lost infectivity, unlike virulent WT (wild type) HIV-1NL4-3. HIV-1NL4-3 variants were capable of CD4+ host entry and reverse transcription as WT HIV-1NL4-3, but lacked ability to complete a full infectious cycle. We currently reveal that viral integration is deregulated in the presence of Rev-NoLS mutations.


Assuntos
Núcleo Celular/metabolismo , Infecções por HIV/virologia , HIV-1/fisiologia , Vírion/metabolismo , Produtos do Gene rev do Vírus da Imunodeficiência Humana/metabolismo , Motivos de Aminoácidos/genética , Linhagem Celular , HIV-1/genética , HIV-1/metabolismo , HIV-1/patogenicidade , Humanos , Mutação , Sinais de Localização Nuclear/química , Sinais de Localização Nuclear/genética , Splicing de RNA , RNA Viral/genética , RNA Viral/metabolismo , Integração Viral , Replicação Viral , Produtos do Gene rev do Vírus da Imunodeficiência Humana/genética
9.
Theranostics ; 8(6): 1575-1590, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29556342

RESUMO

Gene-based therapies represent a promising therapeutic paradigm for the treatment of HIV-1, as they have the potential to maintain sustained viral inhibition with reduced treatment interventions. Such an option may represent a long-term treatment alternative to highly active antiretroviral therapy. Methods: We previously described a therapeutic approach, referred to as transcriptional gene silencing (TGS), whereby small noncoding RNAs directly inhibit the transcriptional activity of HIV-1 by targeting sites within the viral promoter, specifically the 5' long terminal repeat (LTR). TGS differs from traditional RNA interference (RNAi) in that it is characterized by concomitant silent-state epigenetic marks on histones and DNA. To deliver TGS-inducing RNAs, we developed functional RNA conjugates based on the previously reported dual function of the gp120 (A-1) aptamer conjugated to 27-mer Dicer-substrate anti-HIV-1 siRNA (dsiRNA), LTR-362. Results: We demonstrate here that high levels of processed guide RNAs localize to the nucleus in infected T lymphoblastoid CEM cell line and primary human CD4+ T-cells. Treatment of the aptamer-siRNA conjugates induced TGS with an ~10-fold suppression of viral p24 levels as measured at day 12 post infection. To explore the silencing efficacy of aptamer-siRNA conjugates in vivo, HIV-1-infected humanized NOD/SCID/IL2 rγnull mice (hu-NSG) were treated with the aptamer-siRNA conjugates. Systemic delivery of the A-1-stick-LTR-362 27-mer siRNA conjugates suppressed HIV-1 infection and protected CD4+ T cell levels in viremia hu-NSG mice. Principle conclusions: Collectively these data suggest that the gp120 aptamer-dsiRNA conjugate design is suitable for systemic delivery of small RNAs that can be used to suppress HIV-1.


Assuntos
Aptâmeros de Nucleotídeos/genética , RNA Helicases DEAD-box/genética , Regulação Viral da Expressão Gênica , Inativação Gênica , Infecções por HIV/terapia , HIV-1/genética , RNA Viral/genética , Ribonuclease III/genética , Animais , Aptâmeros de Nucleotídeos/metabolismo , Sequência de Bases , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD4-Positivos/virologia , Linhagem Celular Tumoral , RNA Helicases DEAD-box/antagonistas & inibidores , RNA Helicases DEAD-box/metabolismo , Modelos Animais de Doenças , Terapia Genética/métodos , Infecções por HIV/imunologia , Infecções por HIV/patologia , Infecções por HIV/virologia , Repetição Terminal Longa de HIV , HIV-1/crescimento & desenvolvimento , HIV-1/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Camundongos Transgênicos , Conformação de Ácido Nucleico , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , RNA Viral/antagonistas & inibidores , RNA Viral/metabolismo , Ribonuclease III/antagonistas & inibidores , Ribonuclease III/metabolismo , Transcrição Gênica
10.
J Virol ; 92(7)2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29343582

RESUMO

Although current combinatorial antiretroviral therapy (cART) is therapeutically effective in the majority of HIV patients, interruption of therapy can cause a rapid rebound in viremia, demonstrating the existence of a stable reservoir of latently infected cells. HIV latency is therefore considered a primary barrier to HIV eradication. Identifying, quantifying, and purging the HIV reservoir is crucial to effectively curing patients and relieving them from the lifelong requirement for therapy. Latently infected transformed cell models have been used to investigate HIV latency; however, these models cannot accurately represent the quiescent cellular environment of primary latently infected cells in vivo For this reason, in vivo humanized murine models have been developed for screening antiviral agents, identifying latently infected T cells, and establishing treatment approaches for HIV research. Such models include humanized bone marrow/liver/thymus mice and SCID-hu-thy/liv mice, which are repopulated with human immune cells and implanted human tissues through laborious surgical manipulation. However, no one has utilized the human hematopoietic stem cell-engrafted NOD/SCID/IL2rγnull (NSG) model (hu-NSG) for this purpose. Therefore, in the present study, we used the HIV-infected hu-NSG mouse to recapitulate the key aspects of HIV infection and pathogenesis in vivo Moreover, we evaluated the ability of HIV-infected human cells isolated from HIV-infected hu-NSG mice on suppressive cART to act as a latent HIV reservoir. Our results demonstrate that the hu-NSG model is an effective surgery-free in vivo system in which to efficiently evaluate HIV replication, antiretroviral therapy, latency and persistence, and eradication interventions.IMPORTANCE HIV can establish a stably integrated, nonproductive state of infection at the level of individual cells, known as HIV latency, which is considered a primary barrier to curing HIV. A complete understanding of the establishment and role of HIV latency in vivo would greatly enhance attempts to develop novel HIV purging strategies. An ideal animal model for this purpose should be easy to work with, should have a shortened disease course so that efficacy testing can be completed in a reasonable time, and should have immune correlates that are easily translatable to humans. We therefore describe a novel application of the hematopoietic stem cell-transplanted humanized NSG model for dynamically testing antiretroviral treatment, supporting HIV infection, establishing HIV latency in vivo The hu-NSG model could be a facile alternative to humanized bone marrow/liver/thymus or SCID-hu-thy/liv mice in which laborious surgical manipulation and time-consuming human cell reconstitution is required.


Assuntos
Antirretrovirais/farmacologia , Modelos Animais de Doenças , Infecções por HIV/tratamento farmacológico , HIV-1/fisiologia , Latência Viral/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Administração Oral , Animais , Infecções por HIV/metabolismo , Infecções por HIV/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID
11.
Nucleic Acids Res ; 46(1): e6, 2018 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-29077949

RESUMO

Gene therapy by engineering patient's own blood cells to confer HIV resistance can potentially lead to a functional cure for AIDS. Toward this goal, we have previously developed an anti-HIV lentivirus vector that deploys a combination of shRNA, ribozyme and RNA decoy. To further improve this therapeutic vector against viral escape, we sought an additional reagent to target HIV integrase. Here, we report the development of a new strategy for selection and expression of aptamer for gene therapy. We developed a SELEX protocol (multi-tag SELEX) for selecting RNA aptamers against proteins with low solubility or stability, such as integrase. More importantly, we expressed these aptamers in vivo by incorporating them in the terminal loop of shRNAs. This novel strategy allowed efficient expression of the shRNA-aptamer fusions that targeted RNAs and proteins simultaneously. Expressed shRNA-aptamer fusions targeting HIV integrase or reverse transcriptase inhibited HIV replication in cell cultures. Viral inhibition was further enhanced by combining an anti-integrase aptamer with an anti-HIV Tat-Rev shRNA. This construct exhibited efficacy comparable to that of integrase inhibitor Raltegravir. Our strategy for the selection and expression of RNA aptamers can potentially extend to other gene therapy applications.


Assuntos
Aptâmeros de Nucleotídeos/genética , Integrase de HIV/genética , HIV-1/genética , RNA Interferente Pequeno/genética , DNA Polimerase Dirigida por RNA/genética , Síndrome de Imunodeficiência Adquirida/genética , Síndrome de Imunodeficiência Adquirida/terapia , Síndrome de Imunodeficiência Adquirida/virologia , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/metabolismo , Sequência de Bases , Regulação Viral da Expressão Gênica , Terapia Genética/métodos , Infecções por HIV/genética , Infecções por HIV/terapia , Infecções por HIV/virologia , HIV-1/metabolismo , Humanos , Conformação de Ácido Nucleico , Ligação Proteica , RNA Interferente Pequeno/química , RNA Interferente Pequeno/metabolismo , RNA Viral/química , RNA Viral/genética , RNA Viral/metabolismo , Replicação Viral/genética
12.
Sci Rep ; 5: 17808, 2015 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-26643614

RESUMO

We have recently identified a chemotype of small ubiquitin-like modifier (SUMO)-specific protease (SENP) inhibitors. Prior to the discovery of their SENP inhibitory activity, these compounds were found to inhibit HIV replication, but with an unknown mechanism. In this study, we investigated the mechanism of how these compounds inhibit HIV-1. We found that they do not affect HIV-1 viral production, but significantly inhibited the infectivity of the virus. Interestingly, virions produced from cells treated with these compounds could gain entry and carry out reverse transcription, but could not efficiently integrate into the host genome. This phenotype is different from the virus produced from cells treated with the class of anti-HIV-1 agents that inhibit HIV protease. Upon removal of the SUMO modification sites in the HIV-1 integrase, the compound no longer alters viral infectivity, indicating that the effect is related to SUMOylation of the HIV integrase. This study identifies a novel mechanism for inhibiting HIV-1 integration and a new class of small molecules that inhibits HIV-1 via such mechanism that may contribute a new strategy for cure of HIV-1 by inhibiting the production of infectious virions upon activation from latency.


Assuntos
Antivirais/farmacologia , HIV-1/efeitos dos fármacos , HIV-1/fisiologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Integrase de HIV/metabolismo , Inibidores de Integrase de HIV/farmacologia , Humanos , Sumoilação/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
13.
Stem Cells Cloning ; 8: 109-16, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26251620

RESUMO

HIV-1 infection afflicts more than 35 million people worldwide, according to 2014 estimates from the World Health Organization. For those individuals who have access to antiretroviral therapy, these drugs can effectively suppress, but not cure, HIV-1 infection. Indeed, the only documented case for an HIV/AIDS cure was a patient with HIV-1 and acute myeloid leukemia who received allogeneic hematopoietic cell transplantation (HCT) from a graft that carried the HIV-resistant CCR5-∆32/∆32 mutation. Other attempts to establish a cure for HIV/AIDS using HCT in patients with HIV-1 and malignancy have yielded mixed results, as encouraging evidence for virus eradication in a few cases has been offset by poor clinical outcomes due to the underlying cancer or other complications. Such clinical strategies have relied on HIV-resistant hematopoietic stem and progenitor cells that harbor the natural CCR5-∆32/∆32 mutation or that have been genetically modified for HIV-resistance. Nevertheless, HCT with HIV-resistant cord blood remains a promising option, particularly with inventories of CCR5-∆32/∆32 units or with genetically modified, human leukocyte antigen-matched cord blood.

14.
Chem Biol ; 22(3): 379-90, 2015 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-25754473

RESUMO

The C-C chemokine receptor type 5 (CCR5) is a receptor expressed by T cells and macrophages that serves as a coreceptor for macrophage-tropic HIV-1. Loss of CCR5 is associated with resistance to HIV-1. Here, we combine the live-cell-based SELEX with high-throughput sequencing technology to generate CCR5 RNA aptamers capable of specifically targeting HIV-1 susceptible cells (as small interfering RNA [siRNA] delivery agent) and inhibiting HIV-1 infectivity (as antiviral agent) via block of the CCR5 required for HIV-1 to enter cells. One of the best candidates, G-3, efficiently bound and was internalized into human CCR5-expressing cells. The G-3 specifically neutralized R5 virus infection in primary peripheral blood mononuclear cells, and in vivo generated human CD4(+) T cells with a nanomolar inhibitory concentration 50%. G-3 was also capable of transferring functional siRNAs to CCR5-expressing cells. Collectively, the cell-specific, internalizing, CCR5-targeted aptamers and aptamer-siRNA conjugates offer promise for overcoming some of the current challenges of drug resistance in HIV-1 by providing cell-type- or tissue-specific delivery of various therapeutic moieties.


Assuntos
Aptâmeros de Nucleotídeos/administração & dosagem , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Receptores CCR5/genética , Técnica de Seleção de Aptâmeros/métodos , Aptâmeros de Nucleotídeos/genética , Aptâmeros de Nucleotídeos/metabolismo , Sequência de Bases , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Técnicas de Cultura de Células , Células Cultivadas , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/patogenicidade , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/virologia , Macrófagos/imunologia , Macrófagos/virologia , Interferência de RNA , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Receptores CCR5/metabolismo , beta Carioferinas/antagonistas & inibidores , beta Carioferinas/biossíntese , beta Carioferinas/genética
15.
RNA ; 20(12): 1916-28, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25344398

RESUMO

Long noncoding RNAs (lncRNAs) are known to regulate neighboring protein-coding genes by directing chromatin remodeling complexes, imprinting, and X-chromosome inactivation. In this study, we explore the function of lncRNAs in small RNA-triggered transcriptional gene activation (TGA), a process in which microRNAs (miRNAs) or small interfering RNAs (siRNAs) associated with Argonaute (Ago) proteins induce chromatin remodeling and gene activation at promoters with sequence complementarity. We designed a model system with different lncRNA and chromatin environments to elucidate the molecular mechanisms required for mammalian TGA. Using RNA-fluorescence in situ hybridization (FISH) and rapid amplification of cDNA ends (RACE)-PCR, we demonstrated that small RNA-triggered TGA occurs at sites where antisense lncRNAs are transcribed through the reporter gene and promoter. Small RNA-induced TGA coincided with the enrichment of Ago2 at the promoter region, but Ago2-mediated cleavage of antisense lncRNAs was not observed. Moreover, we examined the allele-specific effects of lncRNAs through a Cre-induced inversion of a poly(A) sequence that was designed to block the transcription of antisense lncRNAs through the reporter gene region in an inducible and reversible manner. Termination of nascent antisense lncRNAs abrogated gene activation triggered by small RNAs, and only allele-specific cis-acting antisense lncRNAs, but not trans-acting lncRNAs, were capable of rescuing TGA. Hence, this model revealed that antisense lncRNAs can mediate TGA in cis and not in trans, serving as a molecular scaffold for a small RNA-Ago2 complex and chromatin remodeling.


Assuntos
Proteínas Argonautas/genética , RNA Antissenso/genética , RNA Longo não Codificante/genética , Ativação Transcricional/genética , Animais , Montagem e Desmontagem da Cromatina , Células HeLa , Humanos , Hibridização in Situ Fluorescente , Complexos Multiproteicos/genética , Regiões Promotoras Genéticas , RNA Interferente Pequeno
16.
Angew Chem Int Ed Engl ; 53(44): 11822-7, 2014 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-25219970

RESUMO

siRNA delivery remains a major challenge in RNAi-based therapy. Here, we report for the first time that an amphiphilic dendrimer is able to self-assemble into adaptive supramolecular assemblies upon interaction with siRNA, and effectively delivers siRNAs to various cell lines, including human primary and stem cells, thereby outperforming the currently available nonviral vectors. In addition, this amphiphilic dendrimer is able to harness the advantageous features of both polymer and lipid vectors and hence promotes effective siRNA delivery. Our study demonstrates for the first time that dendrimer-based adaptive supramolecular assemblies represent novel and versatile means for functional siRNA delivery, heralding a new age of dendrimer-based self-assembled drug delivery in biomedical applications.


Assuntos
Dendrímeros/química , Inativação Gênica/imunologia , RNA Interferente Pequeno/imunologia , Humanos
17.
Viruses ; 5(11): 2898-919, 2013 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-24284880

RESUMO

Over the past 15 years we have been investigating an alternative approach to treating HIV-1/AIDS, based on the creation of a disease-resistant immune system through transplantation of autologous, gene-modified (HIV-1-resistant) hematopoietic stem and progenitor cells (GM-HSPC). We propose that the expression of selected RNA-based HIV-1 inhibitors in the CD4+ cells derived from GM-HSPC will protect them from HIV-1 infection and results in a sufficient immune repertoire to control HIV-1 viremia resulting in a functional cure for HIV-1/AIDS. Additionally, it is possible that the subset of protected T cells will also be able to facilitate the immune-based elimination of latently infected cells if they can be activated to express viral antigens. Thus, a single dose of disease resistant GM-HSPC could provide an effective treatment for HIV-1+ patients who require (or desire) an alternative to lifelong antiretroviral chemotherapy. We describe herein the results from several pilot clinical studies in HIV-1 patients and our strategies to develop second generation vectors and clinical strategies for HIV-1+ patients with malignancy who require ablative chemotherapy as part of treatment and others without malignancy. The important issues related to stem cell source, patient selection, conditioning regimen and post-infusion correlative studies become increasingly complex and are discussed herein.


Assuntos
Terapia Genética , Infecções por HIV/genética , Infecções por HIV/terapia , HIV-1/fisiologia , Células-Tronco Hematopoéticas/imunologia , Adolescente , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/transplante , Linfócitos T CD4-Positivos/virologia , Células Cultivadas , Criança , Pré-Escolar , Feminino , Infecções por HIV/imunologia , Infecções por HIV/virologia , Transplante de Células-Tronco Hematopoéticas , Humanos , Lactente , Masculino , Pesquisa Translacional Biomédica , Adulto Jovem
18.
Zhongguo Zhen Jiu ; 33(5): 422-5, 2013 May.
Artigo em Chinês | MEDLINE | ID: mdl-23885616

RESUMO

OBJECTIVE: To compare the efficacy differences between round-sharp needle of new nine-needle and elongated needle for piriformis syndrome, and explore its action mechanism. METHODS: Eighty cases were randomly divided into a round-sharp needle of new nine-needle group (round-sharp needle group) and an elongated needle treatment group (elongated needle group), 40 cases in each group. The round-sharp needle group was treated with round-sharp needle (0.60 mm x 125 mm) at three points in piriformis with triple puncture method, while the elongated needle group was treated with elongated needle of ordinary specifications (0.32 mm x 125 mm) at three points in piriformis with triple puncture method. Besides, the two groups were also treated with routine acupuncture at Weizhong (BL 40) and Yanglingquan (GB 34), 3 times every week, 2 weeks as one course of treatment. After one course of treatment, the clinical effect was evaluated and the pain threshold values were measured before and after treatment in the two groups. RESULTS: The total effective rate in the round-sharp needle group was 92.5% (37/40), which was superior to 77.5% (31/40) in the elongated needle group (P < 0.05). Compared before treatment, the pain threshold values after treatment in two groups were improved significantly (both P < 0.01). The increment of pain threshold value in the round-sharp needle group was higher than that in the elongated needle group (P < 0.01). CONCLUSION: Round-sharp needle of new nine-needle is effective in treatment of piriformis syndrome and is better than ordinary elongated needle, which is related to that it can effectively increase pain threshold value of the local tissue.


Assuntos
Terapia por Acupuntura , Síndrome do Músculo Piriforme/terapia , Punções/métodos , Terapia por Acupuntura/instrumentação , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Agulhas , Resultado do Tratamento , Adulto Jovem
19.
Mol Ther ; 21(1): 192-200, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23164935

RESUMO

One of the most formidable impediments to clinical translation of RNA interference (RNAi) is safe and effective delivery of the siRNAs to the desired target tissue at therapeutic doses. We previously described in vivo cell type-specific delivery of anti-HIV small-interfering RNAs (siRNAs) through covalent conjugation to an anti-gp120 aptamer. In order to improve the utility of aptamers as siRNA delivery vehicles, we chemically synthesized the gp120 aptamer with a 3' 7-carbon linker (7C3), which in turn is attached to a 16-nucleotide 2' OMe/2' Fl GC-rich bridge sequence. This bridge facilitates the noncovalent binding and interchange of various siRNAs with the same aptamer. We show here that this aptamer-bridge-construct complexed with three different Dicer substrate siRNAs (DsiRNAs) results in effective delivery of the cocktail of DsiRNAs in vivo, resulting in knockdown of target mRNAs and potent inhibition of HIV-1 replication. Following cessation of the aptamer-siRNA cocktail treatment, HIV levels rebounded facilitating a follow-up treatment with the aptamer cocktail of DsiRNAs. This follow-up injection resulted in complete suppression of HIV-1 viral loads that extended several weeks beyond the final injection. Collectively, these data demonstrate a facile, targeted approach for combinatorial delivery of antiviral and host DsiRNAs for HIV-1 therapy in vivo.


Assuntos
Aptâmeros de Nucleotídeos/genética , HIV-1/genética , RNA Interferente Pequeno/genética , Animais , Sequência de Bases , Linfócitos T CD4-Positivos/imunologia , Proteína gp120 do Envelope de HIV/genética , Depleção Linfocítica , Camundongos , Camundongos Knockout
20.
Biol Blood Marrow Transplant ; 19(3): 393-7, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23089564

RESUMO

Hematopoietic cell transplantation (HCT) using CCR5-Δ32/Δ32 stem cells from an adult donor has resulted in the only known cure of human immunodeficiency virus (HIV) infection. However, it is not feasible to repeat this procedure except rarely because of the low incidence of the CCR5-Δ32 allele, the availability of only a small number of potential donors for most patients, and the need for a very close human leukocyte antigen (HLA) match between adult donors and recipients. In contrast, cord blood (CB) transplantations require significantly less stringent HLA matching. Therefore, our hypothesis is that cure of HIV infections by HCT can be accomplished much more readily using umbilical CB stem cells obtained from a modestly sized inventory of cryopreserved CCR5-Δ32/Δ32 CB units. To test this hypothesis, we developed a screening program for CB units and are developing an inventory of CCR5-Δ32/Δ32 cryopreserved units available for HCT. Three hundred such units are projected to provide for white pediatric patients a 73.6% probability of finding an adequately HLA matched unit with a cell dose of ≥2.5 × 10(7) total nucleated cells (TNCs)/kg and a 27.9% probability for white adults. With a cell dose of ≥1 × 10(7) TNCs/kg, the corresponding projected probabilities are 85.6% and 82.1%. The projected probabilities are lower for ethnic minorities. Impetus for using CB HCT was provided by a transplantation of an adult with acute myelogenous leukemia who was not HIV infected. The HCT was performed with a CCR5-Δ32/Δ32 CB unit, and posttransplantation in vitro studies indicated that the patient's peripheral blood mononuclear cells were resistant to HIV infection.


Assuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical , Leucemia Mieloide Aguda/terapia , Leucócitos Mononucleares/imunologia , Receptores CCR5/genética , Deleção de Sequência , Adulto , Bancos de Sangue , Células Cultivadas , Criança , Criopreservação , Infecções por HIV/imunologia , Infecções por HIV/patologia , Infecções por HIV/terapia , Infecções por HIV/virologia , Antígenos HLA/genética , Antígenos HLA/imunologia , Teste de Histocompatibilidade , Humanos , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/patologia , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/virologia , Probabilidade , Receptores CCR5/imunologia , Quimeras de Transplante/imunologia , Doadores não Relacionados , População Branca
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