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1.
Front Mol Biosci ; 11: 1387859, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38948080

RESUMEN

Acute ischemic stroke is the most common cause of neurologic dysfunction caused by focal brain ischemia and tissue injury. Diabetes is a major risk factor of stroke, exacerbating disease management and prognosis. Therefore, discovering new diagnostic markers and therapeutic targets is critical for stroke prevention and treatment. Extracellular vesicles (EVs), with their distinctive properties, have emerged as promising candidates for biomarker discovery and therapeutic application. This case-control study utilized mass spectrometry-based proteomics to compare EVs from non-diabetic stroke (nDS = 14), diabetic stroke (DS = 13), and healthy control (HC = 12) subjects. Among 1288 identified proteins, 387 were statistically compared. Statistical comparisons using a general linear model (log2 foldchange ≥0.58 and FDR-p≤0.05) were performed for nDS vs HC, DS vs HC, and DS vs nDS. DS vs HC and DS vs nDS comparisons produced 123 and 149 differentially expressed proteins, respectively. Fibrinogen gamma chain (FIBG), Fibrinogen beta chain (FIBB), Tetratricopeptide repeat protein 16 (TTC16), Proline rich 14-like (PR14L), Inhibitor of nuclear factor kappa-B kinase subunit epsilon (IKKE), Biorientation of chromosomes in cell division protein 1-like 1 (BD1L1), and protein PR14L exhibited significant differences in the DS group. The pathway analysis revealed that the complement system pathways were activated, and blood coagulation and neuroprotection were inhibited in the DS group (z-score ≥2; p ≤ 0.05). These findings underscore the potential of EVs proteomics in identifying biomarkers for stroke management and prevention, warranting further clinical investigation.

2.
Arch Microbiol ; 206(7): 288, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38834761

RESUMEN

Bone infections caused by Staphylococcus aureus may lead to an inflammatory condition called osteomyelitis, which results in progressive bone loss. Biofilm formation, intracellular survival, and the ability of S. aureus to evade the immune response result in recurrent and persistent infections that present significant challenges in treating osteomyelitis. Moreover, people with diabetes are prone to osteomyelitis due to their compromised immune system, and in life-threatening cases, this may lead to amputation of the affected limbs. In most cases, bone infections are localized; thus, early detection and targeted therapy may prove fruitful in treating S. aureus-related bone infections and preventing the spread of the infection. Specific S. aureus components or overexpressed tissue biomarkers in bone infections could be targeted to deliver active therapeutics, thereby reducing drug dosage and systemic toxicity. Compounds like peptides and antibodies can specifically bind to S. aureus or overexpressed disease markers and combining these with therapeutics or imaging agents can facilitate targeted delivery to the site of infection. The effectiveness of photodynamic therapy and hyperthermia therapy can be increased by the addition of targeting molecules to these therapies enabling site-specific therapy delivery. Strategies like host-directed therapy focus on modulating the host immune mechanisms or signaling pathways utilized by S. aureus for therapeutic efficacy. Targeted therapeutic strategies in conjunction with standard surgical care could be potential treatment strategies for S. aureus-associated osteomyelitis to overcome antibiotic resistance and disease recurrence. This review paper presents information about the targeting strategies and agents for the therapy and diagnostic imaging of S. aureus bone infections.


Asunto(s)
Antibacterianos , Osteomielitis , Infecciones Estafilocócicas , Staphylococcus aureus , Osteomielitis/microbiología , Osteomielitis/tratamiento farmacológico , Humanos , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/fisiología , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Antibacterianos/uso terapéutico , Biopelículas/efectos de los fármacos , Animales
3.
Nanomaterials (Basel) ; 14(7)2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38607128

RESUMEN

High-quality perovskite thin films are typically produced via solvent engineering, which results in efficient perovskite solar cells (PSCs). Nevertheless, the use of hazardous solvents like precursor solvents (N-Methyl-2-pyrrolidone (NMP), dimethyl sulfoxide (DMSO), dimethylformamide (DMF), gamma-butyrolactone (GBL)) and antisolvents (chlorobenzene (CB), dibutyl ether (DEE), diethyl ether (Et2O), etc.) is crucial to the preparation of perovskite solutions and the control of perovskite thin film crystallization. The consumption of hazardous solvents poses an imminent threat to both the health of manufacturers and the environment. Consequently, before PSCs are commercialized, the current concerns about the toxicity of solvents must be addressed. In this study, we fabricated highly efficient planar PSCs using a novel, environmentally friendly method. Initially, we employed a greener solvent engineering approach that substituted the hazardous precursor solvents with an environmentally friendly solvent called triethyl phosphate (TEP). In the following stage, we fabricated perovskite thin films without the use of an antisolvent by employing a two-step procedure. Of all the greener techniques used to fabricate PSCs, the FTO/SnO2/MAFAPbI3/spiro-OMeTAD planar device configuration yielded the highest PCE of 20.98%. Therefore, this work addresses the toxicity of the solvents used in the perovskite film fabrication procedure and provides a promising universal method for producing PSCs with high efficiency. The aforementioned environmentally friendly approach might allow for PSC fabrication on an industrial scale in the future under sustainable conditions.

4.
Small ; : e2305694, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38078786

RESUMEN

A nano-micro heterostructure has been established to address the challenges of selectivity, stress, pitting corrosion, and long-term durability of anodes in unpurified seawater. The heterostructure comprised NiOOH nanosheets embedded within a high surface area Ni(OH)2 microarray, and the surface structure is further functionalized with sulfate (SOx ). This cation-selective protective layer impedes chloride (Cl- ) diffusion and abstracts H from reaction intermediates, leading to enhanced selectivity and corrosion resistance of the anode. The multilevel porosity within the randomly oriented nanosheets and the underlying support provide short diffusion channels for ions and mass migration, ensuring efficient ion transport and long-term structural and mechanical durability of the active sites, even at high current density. Remarkably, the catalyst requires a small input voltage of 400 mV to deliver a current density of 1 A cm-2 and maintains it for over 168 h without noticeable degradation or hypochlorite formation. Spectroscopic analysis and density functional theory (DFT) calculations reveal that the Ni electronic structure in the +3 valence state, its strong structural interaction with the underlying microarray, and the functionality of SOx significantly reduce the required potential for O-O coupling.

5.
Adv Mater ; 35(40): e2300812, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37357903

RESUMEN

Immune therapeutics holds great promise in the treatment of type 1 diabetes (T1D). Nonetheless, their progress is hampered by limited efficacy, equipoise, or issues of safety. To address this, a novel and specific nanodelivery platform for T1D that targets high endothelial venules (HEVs) presented in the pancreatic lymph nodes (PLNs) and pancreas is developed. Data indicate that the pancreata of nonobese diabetic (NOD) mice and patients with T1D are unique in their expression of newly formed HEVs. Anti-CD3 mAb is encapsulated in poly(lactic-co-glycolic acid)-poly(ethylene glycol) nanoparticles (NPs), the surfaces of which are conjugated with MECA79 mAb that recognizes HEVs. Targeted delivery of these NPs improves accumulation of anti-CD3 mAb in both the PLNs and pancreata of NOD mice. Treatment of hyperglycemic NOD mice with MECA79-anti-CD3-NPs results in significant reversal of T1D compared to those that are untreated, treated with empty NPs, or provided free anti-CD3. This effect is associated with a significant reduction of T effector cell populations in the PLNs and a decreased production of pro-inflammatory cytokine in the mice treated with MECA79-anti-CD3-NPs. In summary, HEV-targeted therapeutics may be used as a means by which immune therapeutics can be delivered to PLNs and pancreata to suppress autoimmune diabetes effectively.


Asunto(s)
Diabetes Mellitus Tipo 1 , Humanos , Ratones , Animales , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Ratones Endogámicos NOD , Páncreas
6.
Adv Biol (Weinh) ; 6(7): e2200005, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35398976

RESUMEN

The anticancer property of silver-copper metallic nanoparticles (AgCu-NPs) is of greater interest in cancer therapeutics; however, its off-target toxicity limits its therapeutic application. Exosomes emerge as one of the leading idiosyncratic nanocarrier choices for cancer therapeutics due to their size, stability, and phenotypic diversity; however, to encapsulate NPs in extracellular vesicles (EVs) without disrupting their inherited functions is far from the expectations. Here, the loading strategy of AgCu-NP conjugated with wheat germ agglutinin (AgCu-NP-WGA) in exosomes during biogenesis for the targeted delivery of anticancer therapeutics to breast cancer is reported. Based on the intrinsic mechanism of endocytosis of WGA, results show that internalization of WGA or AgCu-NP-WGA bypasses the lysosomal pathway and recycles in EVs. On the contrary, the transport of naked AgCu-NPs to lysosomes; mechanistically, an acidic environment causes oxidation of AgCu-NP. Next, the analysis of EVs harvested by differential centrifugation shows that only AgCu-NPs-WGA (Exo-NP) retain their metallic state. Furthermore, Exo-NP cytotoxicity results manifest that MCF10A-derived Exo-NPs are toxic to its homologous breast cancer cells (MCF-7 and MDA-MB 231) and nontoxic to heterologous cancers NC1-1975 and MCF 10A. In conclusion, this study shows the self-assembly of AgCu-NP in exosomes to target and deliver therapeutics for breast cancer.


Asunto(s)
Neoplasias de la Mama , Exosomas , Nanopartículas del Metal , Neoplasias de la Mama/tratamiento farmacológico , Cobre/farmacología , Exosomas/metabolismo , Femenino , Humanos , Nanopartículas del Metal/uso terapéutico , Plata/farmacología , Aglutininas del Germen de Trigo/metabolismo
7.
ACS Appl Mater Interfaces ; 14(18): 20443-20454, 2022 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-35138809

RESUMEN

The accomplishment of seawater electrolysis to produce green hydrogen energy needs an efficient and durable electrocatalyst with high selectivity and corrosion resistance. Here we report a free-standing amorphous nanostructured oxygen evolution reaction (OER) electrocatalyst with microvoids developed by embedding Gd-doped Mn3O4 nanosheets in a CuO-Cu(OH)2 nanostructure array (Gd-Mn3O4@ CuO-Cu(OH)2. The surface oxygen vacancies modulated the electronic structure of the catalyst and offered active sites with optimal chemisorption energy to OER intermediates. The hierarchical surface structure provides a large specific surface area, high electrical conductivity, ionic mobility, intrinsic activity for each active site, and efficient charge transfer, leading to an outstanding catalytic performance. The enhanced structural, chemical, and corrosion resistance ensures effectiveness as an anode in direct seawater electrolysis. Specifically, it needs an input voltage of 1.63 V to deliver a current density of 500 mA cm-2 in alkaline seawater, with the stability of more than 75 h of continuous electrolysis without hypochlorite formation. The high Faradaic efficiency demonstrates its potential for hydrogen fuel production from seawater.

8.
Neuromolecular Med ; 24(3): 339-351, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-34811658

RESUMEN

Neuronal exosomes play a crucial role in intercellular communication in the brain and represent a promising biomarker for neurological diseases, including stroke. However, limited techniques are available for isolating neuronal exosomes due to their small number in the serum exosomes. Thus, the development of efficient tools with brain-specific markers is needed. Here, we show the optimization of an immunoaffinity assay-based isolation protocol for specific exosomes or neuronally derived exosomes (NDE). Our results demonstrated that one-micron functionalized magnetic beads successfully separated CD63+ and L1CAM+ exosomes from serum. The size and shape of exosomes or exosomes pulled by beads were confirmed by Dynamic light scattering and Transmission electron microscopy; also, beads were well resolved in conventional flow cytometry analysis, which revealed that CD63-pulled serum exosomes had 5% expression of L1CAM. Furthermore, transmission electron microscopy showed that exosomes eluted from magnetic beads retained their original size, shape, and form without any damage. Furthermore, we showed isolation of NDE using GluR2/3-capturing antibody (α-Amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptor) using an optimized immunoaffinity bead assay utilizing 100 µl serum of stroke patients or age-matched healthy group. GluR2/3-captured exosomes were confirmed by western blot analysis. The western blot analysis showed a significant increase in the 35KDa subunit of GluR2/3 receptor protein in the exosomes of stroke patients compared to the healthy group. In addition, the multimeric GluR2/3 receptor protein in exosomes was further validated by the presence of the GluR2 subunit. Thus, our study shows GluR3/2 may be an effective candidate to isolate neuronal exosomes.


Asunto(s)
Exosomas , Molécula L1 de Adhesión de Célula Nerviosa , Accidente Cerebrovascular , Biomarcadores , Exosomas/metabolismo , Humanos , Molécula L1 de Adhesión de Célula Nerviosa/metabolismo , Neuronas/metabolismo , Proteínas/metabolismo , Accidente Cerebrovascular/metabolismo
9.
Polymers (Basel) ; 13(22)2021 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-34833206

RESUMEN

In this research work, we studied the microwave properties of multi-wall carbon nanotube (MWCNT) surface functionalized with metallic oxides composites. Three different concentrations (5%, 10%, and 20%) of metallic oxides were used, namely cobalt, iron, and cobalt ferrite. The surface-decorated CNTS were impregnated into polyurethane (PU) matrix. The surface-decorated MWCNTs and the MWCNTs-PU composites were characterized using electron microscopy. The dielectric properties of the samples are studied using an open-ended coaxial probe technique in a wide frequency range of (5-50 GHz). The metallic oxide-decorated surface MWCNTs-PU composites demonstrated different microwave-frequency absorption characteristics depending on the concentration of the metallic oxides.

10.
Mol Diagn Ther ; 25(2): 163-180, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33453051

RESUMEN

Stroke is one of the major causes of morbidity and mortality globally, with devastating effects. It is diagnosed mainly by clinical assessment and brain imaging; however, it is challenging to discriminate stroke from similar conditions with parallel presentations. While brain imaging provides detection of stroke infarcts, it does not provide useful information on the biology and prognosis of the underlying disease process. The complex pathophysiology of stroke infarcts is a barrier in developing sensitive diagnostic tools, which consequently has a detrimental effect on development of treatment regimens. Early diagnosis of stroke is vital for better management, but currently there is no diagnostic blood-based biomarker. The cargo of exosomes can give an insight into the physiological or pathophysiological status of the cell. Exosomes have gained great interest as a means of intercellular communication and recently have been explored as a potential biomarker tool. Circulating exosomes in the blood result from of a contribution from all tissues. The sub-population of exosomes released from brain cells circulating in body fluids are known as neuronal exosomes. This overview presents the vital diagnostic function that could be performed by circulating exosomes of neuronal origin in identifying the subtype of stroke, its severity, and the recovery stages. A number of potential biomarkers that are obtained from circulating exosomes have showed promising potential to function as stroke biomarkers; however, further work is needed to characterize the neuronal exosomes and its payload and to determine the pathways it uses in the complex pathophysiology of stroke. The identification is a subset of exosomal biomarkers that are specific to stroke will enhance the early detection and prognosis of the disease.


Asunto(s)
Biomarcadores/sangre , Exosomas/genética , MicroARNs/sangre , Accidente Cerebrovascular/sangre , Diagnóstico Precoz , Humanos , Neuronas/metabolismo , Neuronas/patología , Pronóstico , Accidente Cerebrovascular/genética , Accidente Cerebrovascular/patología
11.
ACS Appl Mater Interfaces ; 13(1): 468-479, 2021 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-33356129

RESUMEN

Oxygen evolution reaction (OER) is a bottleneck process in the water-splitting module for sustainable and clean energy production. Transition metal-based electrocatalysts can be effective as water-splitting catalytic materials because of their appropriate redox properties and natural abundance, but the slow kinetics because of strong adsorption and consequently slow desorption of intermediates on the active sites of catalysts severely hamper the dynamics of the released molecular oxygen and thus remains a formidable challenge. Herein, we report the development of structurally and surface-modified PA-Gd-Ni(OH)2Cl (partially alkylated gadolinium-doped nickel oxychloride) nanoclusters (NCs, size ≤ 3 nm) for enhanced and stable OER catalysis at low overpotential and high turnover frequency. The ameliorated catalytic performance was achieved by controlling the surface coverage of these NCs with hydrophobic ligands and through the incorporation of electronegative atoms to facilitate easy adsorption/desorption of intermediates on the catalyst surface, thus improving the liberation of O2. Such a surface and structural modification and uniform distribution at the nanoscale length are indeed worth considering to selectively tune the catalytic potential and further modernize the electrode materials for the challenging OER process.

12.
Beilstein J Nanotechnol ; 11: 1608-1614, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33134005

RESUMEN

The oxidation of Au/Ag alloy thin films using radio-frequency oxygen plasma was studied in this work. It was demonstrated that there is a phase separation occurring between silver and gold. In addition, it was shown that the preferential oxidation of silver resulted in a solid-state diffusion of silver toward the surface where it oxidized and formed nanoporous microspheres. The gold phase remaining in the film exhibited nanoporosity due to the injected vacancies at the metal/silver oxide interface. Based on the scanning transmission electron microscopy analysis coupled with energy dispersive X-ray mapping a mechanism was proposed based on solid-state diffusion and the Kirkendall effect to explain the different steps occurring during the oxidation process.

13.
Sci Transl Med ; 12(569)2020 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-33177180

RESUMEN

Adoptive cell transfer of ex vivo expanded regulatory T cells (Tregs) has shown immense potential in animal models of auto- and alloimmunity. However, the effective translation of such Treg therapies to the clinic has been slow. Because Treg homeostasis is known to require continuous T cell receptor (TCR) ligation and exogenous interleukin-2 (IL-2), some investigators have explored the use of low-dose IL-2 injections to increase endogenous Treg responses. Systemic IL-2 immunotherapy, however, can also lead to the activation of cytotoxic T lymphocytes and natural killer cells, causing adverse therapeutic outcomes. Here, we describe a drug delivery platform, which can be engineered to autostimulate Tregs with IL-2 in response to TCR-dependent activation, and thus activate these cells in sites of antigen encounter. To this end, protein nanogels (NGs) were synthesized with cleavable bis(N-hydroxysuccinimide) cross-linkers and IL-2/Fc fusion (IL-2) proteins to form particles that release IL-2 under reducing conditions, as found at the surface of T cells receiving stimulation through the TCR. Tregs surface-conjugated with IL-2 NGs were found to have preferential, allograft-protective effects relative to unmodified Tregs or Tregs stimulated with systemic IL-2. We demonstrate that murine and human NG-modified Tregs carrying an IL-2 cargo perform better than conventional Tregs in suppressing alloimmunity in murine and humanized mouse allotransplantation models. In all, the technology presented in this study has the potential to improve Treg transfer therapy by enabling the regulated spatiotemporal provision of IL-2 to antigen-primed Tregs.


Asunto(s)
Interleucina-2 , Linfocitos T Reguladores , Animales , Ratones , Nanogeles , Receptores de Antígenos de Linfocitos T , Transducción de Señal
14.
PLoS One ; 15(4): e0231276, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32275737

RESUMEN

OBJECTIVES: Alloyed metallic nanoparticles of silver and copper are effective against intracellular infection. However, systemic toxicity may arise due to the non-specific delivery of the nanoparticles. In addressing the issue, this study deals with the targeting of silver-copper-boron (ACB) nanoparticles to infected osteoblasts, which could decrease systemic toxicity and form the basis of targeting specific markers expressed in bone infections. METHODS: ACB nanoparticles were synthesized and conjugated to the Cadherin-11 antibody (OBAb). The effect of targeting nanoparticles against extracellular and intracellular S. aureus was determined by enumeration of bacterial growth. The binding of the targeting nanoparticles to infected osteoblasts as well as the visualization of live/dead bacteria due to treatment was carried out using fluorescence microscopy. MTT assay was used to determine the viability of osteoblasts with different concentrations of the nanoparticles. RESULTS: The ACB nanoparticles conjugated to OBAb (ACB-OBAb) were effective against extracellular S. aureus. The ACB-OBAb nanoparticles showed a 1.32 log reduction of intracellular S. aureus at a concentration of 1mg/L. The ACB-OBAb nanoparticles were able to bind to the infected osteoblast and showed toxicity to osteoblasts at levels ≥20mg/L. Also, the percentage of silver, copper, and boron in the nanoparticles determined the effectiveness of their antibacterial activity. CONCLUSION: The ACB-OBAb nanoparticles were able to target the osteoblasts and demonstrated significant antibacterial activity against intracellular S. aureus. Targeting shows promise as a strategy to target specific markers expressed on infected osteoblasts for efficient nanoparticle delivery, and further animal studies are recommended to test its efficacy in vivo.


Asunto(s)
Aleaciones/farmacología , Huesos/citología , Boro/farmacología , Cobre/farmacología , Espacio Intracelular/microbiología , Nanopartículas del Metal/química , Plata/farmacología , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/farmacología , Cadherinas/inmunología , Línea Celular , Endocitosis/efectos de los fármacos , Humanos , Espacio Intracelular/efectos de los fármacos , Nanopartículas del Metal/ultraestructura , Pruebas de Sensibilidad Microbiana , Osteoblastos/efectos de los fármacos , Osteoblastos/microbiología
15.
Expert Opin Investig Drugs ; 29(3): 221-236, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32031422

RESUMEN

Introduction: Type 1 diabetes (T1D) is an autoimmune disease that results from the destruction of insulin-producing beta cells in the pancreas; it leads to the under or nonproduction of insulin. T1D is associated with numerous life-threatening micro- and macro-vascular complications and early deaths, hence the development of preventative strategies is a priority for research.Areas covered: The authors outline the drawbacks of available treatments for T1D and assess the three key strategies for prevention, including immunomodulatory therapies which hold the most potential. This article examines CTLA4-Ig and its efficacy and safety profiles. Finally, the pharmacokinetic parameters and pharmacodynamic markers of abatacept are shown in vivo and in clinical trials, guiding dosage regimen recommendations for future investigational studies.Expert opinion: Immunomodulation is one of the promising strategies for decelerating the progression of beta-cell destruction after the onset of T1D. It holds the advantage of specific immune modulation without systemic general immunosuppression. Preclinical and clinical studies have yielded promising data on the use of CTLA4-Ig in T1D. Variations in response to CTLA4-Ig might be partially explained by the existence of multiple T1D subtypes with varying baseline innate inflammatory/regulatory bias and the rate of C-peptide decline.


Asunto(s)
Abatacept/administración & dosificación , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Inmunosupresores/administración & dosificación , Abatacept/efectos adversos , Abatacept/farmacología , Animales , Péptido C/metabolismo , Diabetes Mellitus Tipo 1/inmunología , Progresión de la Enfermedad , Relación Dosis-Respuesta a Droga , Humanos , Inmunosupresores/efectos adversos , Inmunosupresores/farmacología
16.
JCI Insight ; 3(20)2018 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-30333312

RESUMEN

Recent studies in cancer research have focused intensely on the antineoplastic effects of immune checkpoint inhibitors. While the development of these inhibitors has progressed successfully, strategies to further improve their efficacy and reduce their toxicity are still needed. We hypothesized that the delivery of anti-PD-1 antibody encapsulated in PLGA nanoparticles (anti-PD-1 NPs) to the spleen would improve the antitumor effect of this agent. Unexpectedly, we found that mice treated with a high dose of anti-PD-1 NPs exhibited significantly higher mortality compared with those treated with free anti-PD-1 antibody, due to the overactivation of T cells. Administration of anti-PD-1 NPs to splenectomized LT-α-/- mice, which lack both lymph nodes and spleen, resulted in a complete reversal of this increased mortality and revealed the importance of secondary lymphoid tissues in mediating anti-PD-1-associated toxicity. Attenuation of the anti-PD-1 NPs dosage prevented toxicity and significantly improved its antitumor effect in the B16-F10 murine melanoma model. Furthermore, we found that anti-PD-1 NPs undergo internalization by DCs in the spleen, leading to their maturation and the subsequent activation of T cells. Our findings provide important clues that can lead to the development of strategies to enhance the efficacy of immune checkpoint inhibitors.


Asunto(s)
Antineoplásicos Inmunológicos/administración & dosificación , Células Dendríticas/inmunología , Portadores de Fármacos/química , Neoplasias/tratamiento farmacológico , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Animales , Antineoplásicos Inmunológicos/toxicidad , Línea Celular Tumoral/trasplante , Citocinas/inmunología , Citocinas/metabolismo , Células Dendríticas/efectos de los fármacos , Células Dendríticas/metabolismo , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Linfotoxina-alfa/genética , Ratones , Ratones Noqueados , Nanopartículas/química , Neoplasias/inmunología , Neoplasias/mortalidad , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Receptor de Muerte Celular Programada 1/inmunología , Bazo/citología , Bazo/efectos de los fármacos , Bazo/inmunología , Resultado del Tratamiento
17.
J Clin Invest ; 128(11): 4770-4786, 2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30277476

RESUMEN

The targeted delivery of therapeutic drugs to lymph nodes (LNs) provides an unprecedented opportunity to improve the outcomes of transplantation and immune-mediated diseases. The high endothelial venule is a specialized segment of LN vasculature that uniquely expresses peripheral node addressin (PNAd) molecules. PNAd is recognized by MECA79 mAb. We previously generated a MECA79 mAb-coated microparticle (MP) that carries tacrolimus. Although this MP trafficked to LNs, it demonstrated limited therapeutic efficacy in our transplant model. Here, we have synthesized a nanoparticle (NP) as a carrier of anti-CD3, and optimized the conjugation strategy to coat the NP surface with MECA79 mAb (MECA79-anti-CD3-NP) to enhance LN accumulation. As compared with nonconjugated NPs, a significantly higher quantity of MECA79-NPs accumulated in the draining lymph node (DLN). Many MECA79-NPs underwent internalization by T cells and dendritic cells within the LNs. Short-term treatment of murine cardiac allograft recipients with MECA79-anti-CD3-NP resulted in significantly prolonged allograft survival in comparison with the control groups. Prolonged graft survival following treatment with MECA79-anti-CD3-NP was characterized by a significant increase in intragraft and DLN Treg populations. Treg depletion abrogated the prolongation of heart allograft survival. We believe this targeted approach of drug delivery could redefine the methods of administering immune therapeutics in transplantation.


Asunto(s)
Anticuerpos Monoclonales de Origen Murino/farmacología , Portadores de Fármacos/farmacología , Supervivencia de Injerto/efectos de los fármacos , Trasplante de Corazón , Ganglios Linfáticos/inmunología , Nanopartículas/uso terapéutico , Tacrolimus/farmacología , Aloinjertos , Animales , Anticuerpos Monoclonales de Origen Murino/química , Células Dendríticas/inmunología , Células Dendríticas/patología , Portadores de Fármacos/química , Supervivencia de Injerto/inmunología , Ganglios Linfáticos/patología , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Nanopartículas/química , Linfocitos T/inmunología , Tacrolimus/química
18.
Nanomedicine ; 13(7): 2241-2250, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28599795

RESUMEN

Treatment of osteomyelitis by conventional antibiotics has proven to be challenging due to limited accessibility to this unique location. Inorganic routes against bacterial infection have been reported for external and topical applications, however in vivo application of these antimicrobials has not been fully explored. Targeted delivery of metallic nanoparticles with inherent antimicrobial activity represents an alternative means of overcoming the challenges posed by multidrug-resistant bacteria and may potentially reduce overall morbidity. In this study we utilized silver-copper-boron composite nanoparticles in an attempt to eradicate S. aureus bone infection in mice. Our results demonstrate effective response when nanoparticles were administered via i.v. or i.m. route (1mg/kg dose) where 99% of bacteria were eliminated in an induced osteomyelitis mouse model. The 1mg/kg dose was neither toxic nor produced any adverse immune response, hence it is believed that metallic nanoparticles present an alternative to antibiotics for the treatment of bone infection.


Asunto(s)
Antibacterianos/uso terapéutico , Boro/uso terapéutico , Cobre/uso terapéutico , Nanopartículas del Metal/uso terapéutico , Plata/uso terapéutico , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus/efectos de los fármacos , Animales , Antibacterianos/administración & dosificación , Biopelículas/efectos de los fármacos , Huesos/microbiología , Boro/administración & dosificación , Cobre/administración & dosificación , Femenino , Nanopartículas del Metal/administración & dosificación , Ratones , Ratones Endogámicos BALB C , Osteomielitis/tratamiento farmacológico , Osteomielitis/microbiología , Plata/administración & dosificación , Infecciones Estafilocócicas/microbiología
19.
Nanotoxicology ; 10(8): 1061-74, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-26956548

RESUMEN

Nanoparticles (NPs) are increasingly being commercialized for use in biomedicine. NP toxicity following acute or chronic exposure has been described, but mechanistic insight into this process remains incomplete. Recent evidence from in vitro studies suggested a role for NLRP3 in NP cytotoxicity. In this study, we investigated the effect of systemic administration of composite inorganic NP, consisting of Ag:Cu:B (dose range 1-20 mg/kg), on the early acute (4-24 h post-exposure) and late phase response (96 h post-exposure) in normal and NLRP3-deficient mice. Our findings indicate that systemic exposure (≥2 mg/kg) was associated with acute liver injury due to preferential accumulation of NP in this organ and resulted in elevated AST, ALT and LDH levels. Moreover, within 24 h of NP administration, there was a dose-dependent increase in intraperitoneal neutrophil recruitment and upregulation in gene expression of several proinflammatory mediators, including TNF-α, IL-1ß and S100A9. Histological analysis of liver tissue revealed evidence of dose-dependent hepatocyte necrosis, increase in sinusoidal Kupffer cells, lobular granulomas and foci of abscess formation which were most pronounced at 24 h following NP administration. NP deposition in the liver led to a significant upregulation in gene expression of S100A9, an endogenous danger signal recognition molecule of phagocytes, IL-1ß and IL-6. The extent of proinflammatory cytokine activation and hepatotoxicity was significantly attenuated in mice deficient in the NLRP3 inflammasome, demonstrating the critical role of this innate immune system recognition receptor in the response to NP.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Hígado/efectos de los fármacos , Nanopartículas del Metal/toxicidad , Proteína con Dominio Pirina 3 de la Familia NLR/deficiencia , Plata/toxicidad , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas/inmunología , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Citometría de Flujo , Inmunidad Innata/efectos de los fármacos , Interleucina-1beta/genética , Interleucina-6/genética , Macrófagos del Hígado/efectos de los fármacos , Macrófagos del Hígado/patología , Hígado/inmunología , Hígado/patología , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Tamaño de la Partícula , Plata/farmacocinética , Distribución Tisular , Factor de Necrosis Tumoral alfa/genética
20.
Nanomaterials (Basel) ; 5(1): 63-89, 2015 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-28347000

RESUMEN

Localized magnetic hyperthermia using magnetic nanoparticles (MNPs) under the application of small magnetic fields is a promising tool for treating small or deep-seated tumors. For this method to be applicable, the amount of MNPs used should be minimized. Hence, it is essential to enhance the power dissipation or heating efficiency of MNPs. Several factors influence the heating efficiency of MNPs, such as the amplitude and frequency of the applied magnetic field and the structural and magnetic properties of MNPs. We discuss some of the physics principles for effective heating of MNPs focusing on the role of surface anisotropy, interface exchange anisotropy and dipolar interactions. Basic magnetic properties of MNPs such as their superparamagnetic behavior, are briefly reviewed. The influence of temperature on anisotropy and magnetization of MNPs is discussed. Recent development in self-regulated hyperthermia is briefly discussed. Some physical and practical limitations of using MNPs in magnetic hyperthermia are also briefly discussed.

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