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1.
Cancer Lett ; : 217102, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38969157

RESUMO

Triple-negative breast cancer (TNBC) is the most lethal subtype of breast cancer. Hypoxia-activated prodrugs (HAPs) have shown promise as potential therapeutic agents for TNBC. While increasing hypoxia levels may promote the HAP activation, it raises concerns regarding HIF1α-dependent drug resistance. It is desirable to develop a targeted approach that enhances tumor hypoxia for HAP activation without promoting HIF1α-dependent drug resistance in TNBC treatment. Herein, we proposed a multi-responsive carrier-free self-assembled nanomedicine named AQ4N@CA4T1ASO. This nanomedicine first targeted tumors by the TNBC-targeting aptamers (T1), and then disassembled in the reductive and acidic conditions within tumors. The released Combretastatin 4 (CA4) could exacerbate hypoxia, thereby promoting the conversion of inactive Banoxantrone (AQ4N) to its active form, AQ4. Simultaneously, the released antisense oligonucleotide (ASO) could attenuate hypoxia-induced HIF1α mRNA expression, thereby sensitizing the tumor to chemotherapy. Overall, this smart nanomedicine represents a profound targeted therapy strategy, combining "hypoxia-potentiating, hypoxia-activated, chemo-sensitization" approaches for TNBC treatment. In vivo study demonstrated significant suppression of tumor growth, highlighting the promising potential of this nanomedicine for future clinical translation.

2.
Proc Natl Acad Sci U S A ; 121(29): e2401136121, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38985762

RESUMO

Hemostasis relies on a reaction network of serine proteases and their cofactors to form a blood clot. Coagulation factor IXa (protease) plays an essential role in hemostasis as evident from the bleeding disease associated with its absence. RNA aptamers specifically targeting individual coagulation factors have potential as anticoagulants and as probes of the relationship between structure and function. Here, we report X-ray structures of human factor IXa without a ligand bound to the active site either in the apo-form or in complex with an inhibitory aptamer specific for factor IXa. The aptamer binds to an exosite in the catalytic domain and allosterically distorts the active site. Our studies reveal a conformational ensemble of IXa states, wherein large movements of Trp215 near the active site drive functional transitions between the closed (aptamer-bound), latent (apo), and open (substrate-bound) states. The latent state of the apo-enzyme may bear on the uniquely poor catalytic activity of IXa compared to other coagulation proteases. The exosite, to which the aptamer binds, has been implicated in binding VIIIa and heparin, both of which regulate IXa function. Our findings reveal the importance of exosite-driven allosteric modulation of IXa function and new strategies to rebalance hemostasis for therapeutic gain.


Assuntos
Aptâmeros de Nucleotídeos , Fator IXa , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/metabolismo , Fator IXa/metabolismo , Fator IXa/química , Fator IXa/antagonistas & inibidores , Humanos , Regulação Alostérica , Domínio Catalítico , Cristalografia por Raios X , Modelos Moleculares , Ligação Proteica , Anticoagulantes/química , Anticoagulantes/metabolismo , Anticoagulantes/farmacologia
3.
Proc Natl Acad Sci U S A ; 121(29): e2404060121, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38985770

RESUMO

DNA aptamers have emerged as novel molecular tools in disease theranostics owing to their high binding affinity and specificity for protein targets, which rely on their ability to fold into distinctive three-dimensional (3D) structures. However, delicate atomic interactions that shape the 3D structures are often ignored when designing and modeling aptamers, leading to inefficient functional optimization. Challenges persist in determining high-resolution aptamer-protein complex structures. Moreover, the experimentally determined 3D structures of DNA molecules with exquisite functions remain scarce. These factors impede our comprehension and optimization of some important DNA aptamers. Here, we performed a streamlined solution NMR-based structural investigation on the 41-nt sgc8c, a prominent DNA aptamer used to target membrane protein tyrosine kinase 7, for cancer theranostics. We show that sgc8c prefolds into an intricate three-way junction (3WJ) structure stabilized by long-range tertiary interactions and extensive base-base stackings. Delineated by NMR chemical shift perturbations, site-directed mutagenesis, and 3D structural information, we identified essential nucleotides constituting the key functional elements of sgc8c that are centralized at the core of 3WJ. Leveraging the well-established structure-function relationship, we efficiently engineered two sgc8c variants by modifying the apical loop and introducing L-DNA base pairs to simultaneously enhance thermostability, biostability, and binding affinity for both protein and cell targets, a feat not previously attained despite extensive efforts. This work showcases a simplified NMR-based approach to comprehend and optimize sgc8c without acquiring the complex structure, and offers principles for the sophisticated structure-function organization of DNA molecules.


Assuntos
Aptâmeros de Nucleotídeos , Conformação de Ácido Nucleico , Receptores Proteína Tirosina Quinases , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/metabolismo , Aptâmeros de Nucleotídeos/genética , Humanos , Receptores Proteína Tirosina Quinases/metabolismo , Receptores Proteína Tirosina Quinases/química , Receptores Proteína Tirosina Quinases/genética , Modelos Moleculares , Espectroscopia de Ressonância Magnética/métodos , Ligação Proteica , Moléculas de Adesão Celular
4.
Heliyon ; 10(12): e33238, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39022011

RESUMO

Objective and rationale: This study aimed to develop a highly sensitive and selective single-stranded DNA (ssDNA) aptamer targeting cardiac troponin I (cTnI), a crucial biomarker for acute myocardial infarction (AMI). The objective was to fabricate a novel aptamer electrochemical sensor using a composite material of cobalt-nickel metal-organic framework (CoNi-MOF) on screen-printed carbon electrodes (SPCE), leveraging the composite's large surface area and excellent electrical conductivity alongside the aptamer's high affinity for cTnI. Methods: The aptamer electrochemical sensor was fabricated using the CoNi-MOF composite on SPCE and characterized its properties. They conducted electrochemical measurements to assess the sensor's performance in detecting cTnI. The sensor's stability, reproducibility, and electro-catalytic activity were evaluated. Results: The sensor demonstrated linear detection of cTnI over a concentration range of 5-75 pg/mL, with a low limit of detection (LOD) of 13.2 pM. Remarkable stability and reproducibility were observed in cTnI detection. The sensor exhibited exceptional electro-catalytic activity, enabling accurate quantification of cTnI levels in various solutions. Conclusions: This research presents a significant advancement towards the development of reliable, cost-effective, and easily deployable cTnI sensors for clinical applications. The sensor's versatility in detecting cTnI across different concentration ranges highlights its potential utility in diverse clinical settings, particularly for early detection and monitoring of cardiac conditions.

5.
Mol Pharm ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951109

RESUMO

The poor delivery efficiency of nanotherapeutic drugs and their potential off-target toxicity significantly limit their effectiveness and extensive application. An active targeting system with high efficiency and few side effects is a promising strategy for tumor therapy. Herein, a multifunctional nanomedicine Nb2C-PAA-DOX@Apt-M (NDA-M) was constructed for targeted photothermal/chemotherapy (PTT/CHT) combined tumor therapy. The specific targeting ability of aptamer could effectively enhance the absorption of nanomedicine by the MCF-7 cell. By employing Apt-M, the NDA-M nanosheets demonstrated targeted delivery to MCF-7 cells, resulting in enhanced intracellular drug concentration. Under 1060 nm laser irradiation, a rapid temperature increase of the NDA-M was observed within the tumor region to achieve PTT. Meanwhile, CHT was triggered when DOX release was induced by photothermal/acid stimulation. The experimental results demonstrated that aptamer-mediated targeting achieved enhanced PTT/CHT efficacy both in vitro and in vivo. Notably, NDA-M induced complete ablation of solid tumors without any adverse side effects in mice. This study demonstrated new and promising tactics for the development of nanomaterials for targeted tumor therapy.

6.
Biomed Pharmacother ; 177: 117064, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38964179

RESUMO

Macrophages play a critical role in the body's defense against cancer by phagocytosing tumor cells, presenting antigens, and activating adaptive T cells. However, macrophages are intrinsically incapable of delivering targeted cancer immunotherapies. Engineered adoptive cell therapy introduces new targeting and antitumor capabilities by modifying macrophages to enhance the innate immune response of cells and improve clinical efficacy. In this study, we developed engineered macrophage cholesterol-AS1411-M1 (CAM1) for cellular immunotherapy. To target macrophages, cholesterol-AS1411 aptamers were anchored to the surface of M1 macrophages to produce CAM1 without genetic modification or cell damage. CAM1 induced significantly higher apoptosis/mortality than unmodified M1 macrophages in murine breast cancer cells. Anchoring AS1411 on the surface of macrophages provided a novel approach to construct engineered macrophages for tumor immunotherapy.

7.
Talanta ; 278: 126488, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38955098

RESUMO

Fluorogenic RNA aptamers, which specifically bind to fluorogens and dramatically enhance their fluorescence, are valuable for imaging and detecting RNAs and metabolites in living cells. Most fluorogenic RNA aptamers have been identified and engineered through iterative rounds of in vitro selection based on their binding to target fluorogens. While such selection is an efficient approach for generating RNA aptamers, it is less efficient for isolating fluorogenic aptamers because it does not directly screen for fluorogenic properties. In this study, we combined a fluorescence-based in vitro selection technique using water-in-oil microdroplets with an affinity-based selection technique to obtain fluorogenic RNA aptamers. This approach allowed us to identify novel fluorogenic aptamers for a biotin-modified thiazole orange derivative. Our results demonstrate that our approach can expand the diversity of fluorogenic RNA aptamers, thus leading to new applications for the imaging and detection of biomolecules.

8.
ACS Appl Bio Mater ; 7(7): 4679-4689, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38963794

RESUMO

Postoperative peritoneal adhesion (PPA) is a prevalent complication of abdominal surgery, posing a significant hindrance to postsurgical recovery. Although several strategies have been developed to alleviate and prevent adhesions, their efficacy remains unsatisfactory. For the first time, we studied the therapeutic effect and mechanism of our recently developed thermally stable oligonucleotide-based mimetics of hepatocyte growth factor (HGF DNA aptamer) to prevent PPA. The HGF DNA aptamer effectively inhibited canonical TGF-ß1 signaling transduction, partially suppressing mesothelial mesenchymal transition. Additionally, the aptamer, respectively, upregulated and downregulated the expression of tissue plasminogen activator and plasminogen activator inhibitor 1, thereby enhancing fibrinolytic activity. As a pleiotropic factor, the HGF DNA aptamer also enhanced the migratory and proliferative capacities of mesothelial cells. Finally, the aptamer demonstrated a higher level of effectiveness in preventing PPAs than the commercially available antiperitoneal adhesion barrier, Seprafilm. Due to its therapeutic benefits, excellent stability, biosafety, cost-effectiveness, and versatility, the HGF DNA aptamer demonstrates promise for preventing PPA in future clinical settings.


Assuntos
Aptâmeros de Nucleotídeos , Transição Epitelial-Mesenquimal , Fibrinólise , Fator de Crescimento de Hepatócito , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/farmacologia , Fator de Crescimento de Hepatócito/metabolismo , Aderências Teciduais/prevenção & controle , Humanos , Fibrinólise/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Teste de Materiais , Tamanho da Partícula , Complicações Pós-Operatórias/prevenção & controle
9.
Theranostics ; 14(10): 3945-3962, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38994035

RESUMO

Rationale: NLRP3 inflammasome is critical in the development and progression of many metabolic diseases driven by chronic inflammation, but its effect on the pathology of postmenopausal osteoporosis (PMOP) remains poorly understood. Methods: We here firstly examined the levels of NLRP3 inflammasome in PMOP patients by ELISA. Then we investigated the possible mechanisms underlying the effect of NLRP3 inflammasome on PMOP by RNA sequencing of osteoblasts treated with NLRP3 siRNA and qPCR. Lastly, we accessed the effect of decreased NLRP3 levels on ovariectomized (OVX) rats. To specifically deliver NLRP3 siRNA to osteoblasts, we constructed NLRP3 siRNA wrapping osteoblast-specific aptamer (CH6)-functionalized lipid nanoparticles (termed as CH6-LNPs-siNLRP3). Results: We found that the levels of NLRP3 inflammasome were significantly increased in patients with PMOP, and were negatively correlated with estradiol levels. NLRP3 knock-down influenced signal pathways including immune system process, interferon signal pathway. Notably, of the top ten up-regulated genes in NLRP3-reduced osteoblasts, nine genes (except Mx2) were enriched in immune system process, and five genes were related to interferon signal pathway. The in vitro results showed that CH6-LNPs-siNLRP3 was relatively uniform with a dimeter of 96.64 ± 16.83 nm and zeta potential of 38.37 ± 1.86 mV. CH6-LNPs-siNLRP3 did not show obvious cytotoxicity and selectively delivered siRNA to bone tissue. Moreover, CH6-LNPs-siNLRP3 stimulated osteoblast differentiation by activating ALP and enhancing osteoblast matrix mineralization. When administrated to OVX rats, CH6-LNPs-siNLRP3 promoted bone formation and bone mass, improved bone microarchitecture and mechanical properties by decreasing the levels of NLRP3, IL-1ß and IL-18 and increasing the levels of OCN and Runx2. Conclusion: NLRP3 inflammasome may be a new biomarker for PMOP diagnosis and plays a key role in the pathology of PMOP. CH6-LNPs-siNLRP3 has potential application for the treatment of PMOP.


Assuntos
Inflamassomos , Lipossomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Nanopartículas , Osteoblastos , Osteoporose Pós-Menopausa , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Feminino , Humanos , Ratos , Inflamassomos/metabolismo , Nanopartículas/química , Osteoporose Pós-Menopausa/metabolismo , Regulação para Baixo/efeitos dos fármacos , Ratos Sprague-Dawley , RNA Interferente Pequeno/administração & dosagem , Aptâmeros de Nucleotídeos/farmacologia , Aptâmeros de Nucleotídeos/administração & dosagem , Modelos Animais de Doenças , Pessoa de Meia-Idade , Ovariectomia
10.
Talanta ; 278: 126565, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39018762

RESUMO

Bacteria infections pose a serious threat to public health, and it is urgent to develop facile and accurate detection methods. To meet the important need, a potable and high-sensitive surface enhanced Raman scattering (SERS) biosensor based on aptamer recognition and catalytic hairpin assembly (CHA) signal amplification was proposed for point-of-care detection of Staphylococcus aureus (S. aureus). The SERS biosensor contains three parts: recognition probes, SERS sensing chip, and SERS tags. The feasibility of the strategy was verified by gel electrophoresis, and the one-step test route was optimized. The bacteria SERS biosensor has a good linear relationship ranging from 10 to 107 CFU mL-1 with high sensitivity low to 5 CFU mL-1, and shows excellent specificity, uniformity, and repeatability on S. aureus identification and enumeration, which can distinguish S. aureus from other bacteria. The SERS biosensor shows a good recovery rate (95.73 %-109.65 %) for testing S. aureus spiked in milk, and has good practicability for detecting S. aureus infected mouse wound, which provides a facile and reliable approach for detection of trace bacteria in the real samples.

11.
J Chromatogr A ; 1730: 465138, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38970874

RESUMO

In this study, an enhanced selective recognition strategy was employed to construct a novel solid-phase microextraction fiber coating for the detection of 17ß-estradiol, characterized by the combination of aptamer biorecognition and molecularly imprinted polymer recognition. Benefiting from the combination of molecularly imprinted and aptamer, aptamer-molecularly imprinted (Apt-MIP) fiber coating had synergistic recognition effect. The effects of pH, ion concentration, extraction time, desorption time and desorption solvent on the adsorption capacity of Apt-MIP were investigated. The adsorption of 17ß-estradiol on Apt-MIP followed pseudo-second order kinetic model, and the Freundlich isotherm. The process was exothermic and thermodynamically spontaneous. Compared with polymers that only rely on imprinted recognition, non-imprinted recognition or aptamer affinity, Apt-MIP had the best recognition performance, which was 1.30-2.20 times that of these three materials. Furthermore, the adsorption capacity of Apt-MIP for 17ß-estradiol was 885.36-1487.52 times than that of polyacrylate and polydimethylsiloxane/divinylbenzone commercial fiber coatings. Apt-MIP fiber coating had good stability and could be reused for more than 15 times. Apt-MIP solid-phase microextraction coupled with high-performance liquid chromatography was successfully applied to the determination of 17ß-estradiol in pork, chicken, fish and shrimp samples, with satisfactory recoveries of 79.61 %-105.70 % and low limits of detection (0.03 µg/kg). This work provides new perspectives and strategies for sample pretreatment techniques based on molecular imprinting technology and improves analytical performance.

12.
J Hazard Mater ; 476: 135112, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38981234

RESUMO

In light of the significant risks that mycotoxins posed to public health and environmental safety, this research developed an adsorbent MIPs/Apt/AuNPs@ZIF-67 (MA-AZ) utilizing a dual-recognition approach combining molecularly imprinted polymers (MIPs) and aptamer (Apt). This innovative method enabled the effective and highly selective recognition and enrichment of ochratoxin A (OTA). ZIF-67 was utilized as a carrier with a substantial specific surface area, and gold nanoparticles (AuNPs) were loaded on its surface to fix the thiol-modified Apt on the surface of the carrier. Then, an initiator was used to initiate a polymerization reaction, and the generated MIPs coated Apt/AuNPs@ZIF-67, thereby synthesizing the MA-AZ with a "synergistic recognition" effect. The Apt significantly increased the number of recognition sites within the imprinted cavities, and MIPs played roles in identifying targets, fixing and protecting Apt. The combination of the both produced the effect of "1+1>2". The study on the adsorption performance of MA-AZ found that the adsorption capacity of MA-AZ could reach 65.1 mg/g, and the imprinted factor was 5.48. In addition, MA-AZ exhibited excellent stability, specificity, reusability and recovery rate. Thus, this study offers valuable insights for the recognition and enrichment of hazardous substances, and helps to promote the rapid development of safety detection.

13.
ACS Sens ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982801

RESUMO

Celiac patients are required to strictly adhere to a gluten-free diet because even trace amounts of gluten can damage their small intestine and leading to serious complications. Despite increased awareness, gluten can still be present in products due to cross-contamination or hidden ingredients, making regular monitoring essential. With the goal of guaranteeing food safety for consuming labeled gluten-free products, a capacitive aptasensor was constructed to target gliadin, the main allergic gluten protein for celiac disease. The success of capacitive aptasensing was primarily realized by coating a Parylene double-layer (1000 nm Parylene C at the bottom with 400 nm Parylene AM on top) on the electrode surface to ensure both high insulation quality and abundant reactive amino functionalities. Under the optimal concentration of aptamer (5 µM) used for immobilization, a strong linear relationship exists between the amount of gliadin (0.01-1.0 mg/mL) and the corresponding ΔC response (total capacitance decrease during a 20 min monitoring period after sample introduction), with an R2 of 0.9843. The detection limit is 0.007 mg/mL (S/N > 5), equivalent to 0.014 mg/mL (14 ppm) of gluten content. Spike recovery tests identified this system is free from interferences in corn and cassava flour matrices. The analytical results of 24 commercial wheat flour samples correlated well with a gliadin ELISA assay (R2 = 0.9754). The proposed label-free and reagentless capacitive aptasensor offers advantages of simplicity, cost-effectiveness, ease of production, and speediness, making it a promising tool for verifying products labeled as gluten-free (gluten content <20 ppm).

14.
J Nanobiotechnology ; 22(1): 392, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965606

RESUMO

Pancreatic cancer, predominantly pancreatic ductal adenocarcinoma (PDAC), remains a highly lethal malignancy with limited therapeutic options and a dismal prognosis. By targeting the underlying molecular abnormalities responsible for PDAC development and progression, gene therapy offers a promising strategy to overcome the challenges posed by conventional radiotherapy and chemotherapy. This study sought to explore the therapeutic potential of small activating RNAs (saRNAs) specifically targeting the CCAAT/enhancer-binding protein alpha (CEBPA) gene in PDAC. To overcome the challenges associated with saRNA delivery, tetrahedral framework nucleic acids (tFNAs) were rationally engineered as nanocarriers. These tFNAs were further functionalized with a truncated transferrin receptor aptamer (tTR14) to enhance targeting specificity for PDAC cells. The constructed tFNA-based saRNA formulation demonstrated exceptional stability, efficient saRNA release ability, substantial cellular uptake, biocompatibility, and nontoxicity. In vitro experiments revealed successful intracellular delivery of CEBPA-saRNA utilizing tTR14-decorated tFNA nanocarriers, resulting in significant activation of tumor suppressor genes, namely, CEBPA and its downstream effector P21, leading to notable inhibition of PDAC cell proliferation. Moreover, in a mouse model of PDAC, the tTR14-decorated tFNA-mediated delivery of CEBPA-saRNA effectively upregulated the expression of the CEBPA and P21 genes, consequently suppressing tumor growth. These compelling findings highlight the potential utility of saRNA delivered via a designed tFNA nanocarrier to induce the activation of tumor suppressor genes as an innovative therapeutic approach for PDAC.


Assuntos
Aptâmeros de Nucleotídeos , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Receptores da Transferrina , Animais , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Carcinoma Ductal Pancreático/tratamento farmacológico , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/farmacologia , Receptores da Transferrina/metabolismo , Camundongos , Linhagem Celular Tumoral , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Proteínas Estimuladoras de Ligação a CCAAT/genética , Proliferação de Células/efeitos dos fármacos , Terapia Genética/métodos , RNA Interferente Pequeno/farmacologia , Camundongos Nus
15.
Chembiochem ; : e202400444, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38996191

RESUMO

A new DNA aptamer that binds to the target Thiazole Orange-biotin (TO1-biotin) was isolated after nine rounds of in vitro selection. The selection was performed on streptavidin-coated beads with the target bound to the surface and with free dye in solution in higher selection rounds to select for slower off-rate binding. Using next-generation sequencing (NGS), the libraries after the 4th and 9th rounds of selection were sequenced to identify enriched sequences. Several sequence families emerged, showing superior fluorescence enhancement and high affinity for the target compared to the other families obtained by NGS analysis. These sequence families were further studied to understand the binding interactions better. Primary sequence and secondary structure analysis tools were used to identify a hypothetical three-tiered G-quadruplex motif for these families. This indicates that the TO1-biotin DNA aptamer identified here uses a similar ligand-binding topology to the original Mango RNA aptamer.

16.
Annu Rev Biophys ; 53(1): 109-125, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39013026

RESUMO

The relationship between genotype and phenotype, or the fitness landscape, is the foundation of genetic engineering and evolution. However, mapping fitness landscapes poses a major technical challenge due to the amount of quantifiable data that is required. Catalytic RNA is a special topic in the study of fitness landscapes due to its relatively small sequence space combined with its importance in synthetic biology. The combination of in vitro selection and high-throughput sequencing has recently provided empirical maps of both complete and local RNA fitness landscapes, but the astronomical size of sequence space limits purely experimental investigations. Next steps are likely to involve data-driven interpolation and extrapolation over sequence space using various machine learning techniques. We discuss recent progress in understanding RNA fitness landscapes, particularly with respect to protocells and machine representations of RNA. The confluence of technical advances may significantly impact synthetic biology in the near future.


Assuntos
RNA Catalítico , RNA Catalítico/química , RNA Catalítico/genética , RNA Catalítico/metabolismo , Evolução Molecular , Aptidão Genética/genética
17.
Bioorg Med Chem ; 110: 117831, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-39004051

RESUMO

The CD20 antigen is a key target for several diseases including lymphoma and autoimmune diseases. For over 20 years, several monoclonal antibodies were developed to treat CD20-related disorders. As many therapeutic proteins, their clinical use is however limited due to their nature with a costly biotechnological procedure and side effects such as the production of anti-drug neutralizing antibodies. Nucleic acid aptamers have some advantages over mAbs and are currently investigated for clinical use. We herein report the selection of DNA aptamer by using a peptide-based CE-SELEX (Capillary Electrophoresis-Systematic Evolution of Ligands by Exponential Enrichment) method. It was demonstrated that these aptamers bind specifically a CD20-expressing human cell line, with Kd estimated from isothermal titration calorimetry experiments in the micromolar range. This study demonstrates that the CE-SELEX is suitable as alternative method to the conventional Cell-SELEX to discover new cell-targeting compounds.

18.
Luminescence ; 39(7): e4829, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39004775

RESUMO

A ratio luminescence probe was developed for detecting Staphylococcus aureus (S. aureus) based on luminescence energy transfer (LET) using double-wavelength emission (550 nm and 812 nm) upconversion nanoparticles (UCNPs) as donor, gold nanoparticles (AuNPs) as acceptor and the aptamer for S. aureus as the specific recognition and link unit. The LET process could cause luminescence quenching because of the spectral overlap between the acceptor and the donor at 550 nm. In the presence of S. aureus, S. aureus selectively combined with the aptamer, and the AuNPs left the surface of UCNPs, which weakened the quenching effect and restored the luminescence of UCNPs. Based on this, the ratio detection was realized by monitoring the change of the luminescence signal of the probe at 550 nm and taking the luminescence signal at 812 nm as the reference signal. Crucially, the probe has a fast reaction speed, with a reaction time of 25 min, and the detection of S. aureus is realized in the concentration range of 5.0 × 103-3.0 × 105 CFU/ml, with the detection limit of 106 CFU/ml. Therefore, the ratio probe has great potential for detecting of S. aureus in food because of its high sensitivity, fast speed and good selectivity.


Assuntos
Aptâmeros de Nucleotídeos , Transferência de Energia , Ouro , Luminescência , Medições Luminescentes , Nanopartículas Metálicas , Staphylococcus aureus , Staphylococcus aureus/isolamento & purificação , Ouro/química , Nanopartículas Metálicas/química , Aptâmeros de Nucleotídeos/química , Limite de Detecção
19.
Curr Med Chem ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39005126

RESUMO

Bacillus anthracis is a causative agent of the highly mortal disease anthrax. This zoonosis is present in nature, but it is also considered one of the most powerful biological warfare agents. A timely diagnosis is necessary for proper therapy and setting of epidemiological countermeasures. Current diagnostic methods should be used in specialized laboratories or medical facilities because there are only a limited number of methods suitable as hand-held assays or even point-of-care tests for detecting B. anthracis or anthrax diagnosis. The lateral flow tests are an exception in this regard, but these tests also have some limitations. Significant progress has been achieved in point-of-care tests for B. anthracis detection and anthrax diagnosis in various biosensors and bioassays. This review focuses on current hand-held and point-of-care tests that can easily prove anthrax or its causative agent outside the context of specialized facilities.

20.
Eur J Pharm Biopharm ; : 114411, 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39009192

RESUMO

Combination therapy using chemo-photothermal therapy (chemo-PTT) shows great efficacy toward tumor ablation in preclinical studies. Besides, lipopolymersomes as a hybrid nanocarriers, integrate advantages of liposomes and polymersomes in a single platform in order to provide tremendous biocompatibility, biodegradability, noteworthy loading efficacy for both hydrophobic and hydrophilic drugs with adjustable drug release and high stability. In this study, a multipurpose lipopolymersome was fabricated for guided chemotherapy-PTT and CT-scan imaging of melanoma. A lipopolymerosomal hybrid nanovesicle consisting of equal molar ratio of 1,2-dioleoyl-3-trimethylammonium propane (DOTAP) and poly (ethylene glycol)-poly (lactic acid) (PEG-PLA) diblock copolymer (molar ratio 1:1) was fabricated. The nanoparticulate system was prepared through film rehydration technique for encapsulation of doxorubicin (DOX) and indocyanine green (ICG) to form DOX-ICG-LP platform. At the next stage, AS1411 DNA aptamer was conjugated to the surface of lipopolymersome (Apt-DOX-ICG-LP) for selective delivery. The sizes of DOX-ICG-LP and Apt-DOX-ICG-LP were obtained through DLS analysis (61.0 ±â€¯6 and 74 ±â€¯5, respectively). Near Infrared-responsive release pattern of the prepared lipopolymersome was verified in vitro. The formulated platform showed efficient photothermal conversion, and superior stability with acceptable encapsulation efficiency. Consistent with the in vitro studies, NIR-responsive lipopolymersome exhibited significantly higher cellular toxicity for Chemo-PTT versus single anti-cancer treatment. Moreover, superlative tumor shrinkage with favorable survival profile were attained in B16F10 tumor-bearing mice received Apt-DOX-ICG-LP and irradiated with 808 nm laser compared to those treated with either DOX-ICG-LP or Apt-DOX-ICG-LP without laser irradiation. The diagnostic capability of Apt-DOX-ICG-LP was addressed using in vivo NIR imaging, 6 and 24 h post-intravenous administration. The results indicated desirable feature of an established targeted theranostic capability of Apt-DOX-ICG-LP for both diagnostics and dual chemo-PTT of melanoma.

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