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1.
Mol Pharm ; 21(7): 3471-3484, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38872243

RESUMO

Oligonucleotides are short nucleic acids that serve as one of the most promising classes of drug modality. However, attempts to establish a physicochemical evaluation platform of oligonucleotides for acquiring a comprehensive view of their properties have been limited. As the chemical stability and the efficacy as well as the solution properties at a high concentration should be related to their higher-order structure and intra-/intermolecular interactions, their detailed understanding enables effective formulation development. Here, the higher-order structure and the thermodynamic stability of the thrombin-binding aptamer (TBA) and four modified TBAs, which have similar sequences but were expected to have different higher-order structures, were evaluated using ultraviolet spectroscopy (UV), circular dichroism (CD), differential scanning calorimetry (DSC), and nuclear magnetic resonance (NMR). Then, the relationship between the higher-order structure and the solution properties including solubility, viscosity, and stability was investigated. The impact of the higher-order structure on the antithrombin activity was also confirmed. The higher-order structure and intra-/intermolecular interactions of the oligonucleotides were affected by types of buffers because of different potassium concentrations, which are crucial for the formation of the G-quadruplex structure. Consequently, solution properties, such as solubility and viscosity, chemical stability, and antithrombin activity, were also influenced. Each instrumental analysis had a complemental role in investigating the higher-order structure of TBA and modified TBAs. The utility of each physicochemical characterization method during the preclinical developmental stages is also discussed.


Assuntos
Aptâmeros de Nucleotídeos , Dicroísmo Circular , Oligonucleotídeos , Aptâmeros de Nucleotídeos/química , Dicroísmo Circular/métodos , Oligonucleotídeos/química , Varredura Diferencial de Calorimetria/métodos , Viscosidade , Espectroscopia de Ressonância Magnética/métodos , Solubilidade , Termodinâmica , Quadruplex G , Estabilidade de Medicamentos , Humanos
2.
Biochem Biophys Res Commun ; 686: 149179, 2023 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-37922572

RESUMO

Direct delivery of genome-editing proteins into plant tissues could be useful in obtaining DNA-free genome-edited crops obviating the need for backcrossing to remove vector-derived DNA from the host genome as in the case of genetically modified organisms generated using DNA vector. Previously, we successfully delivered Cas9 ribonucleoprotein (RNP) into plant tissue by inserting microneedle array (MNA) physisorbed with Cas9 RNPs. Here, to enhance protein delivery and improve genome-editing efficiency, we introduced a bioactive polymer DMA/HPA/NHS modification to the MNA, which allowed strong bonding between the proteins and MNA. Compared with other modifying agents, this MNA modification resulted in better release of immobilized protein in a plant cytosol-mimicking environment. The delivery of Cas9 RNPs in Arabidopsis thaliana reporter plants was improved from 4 out of 17 leaf tissues when using unmodified MNAs to 9 out of 17 when using the polymer-modified MNAs. Further improvements in delivery efficiency can be envisaged by optimizing the polymer modification conditions, which could have significant implications for the development of more effective plant genome editing techniques.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Edição de Genes/métodos , Ribonucleoproteínas/genética , Ribonucleoproteínas/metabolismo , Citosol/metabolismo , Preparações de Ação Retardada , DNA , Genoma de Planta/genética
3.
Langmuir ; 39(22): 7557-7565, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37225422

RESUMO

Semiconductor nanocrystals or quantum dots (QDs) have gained significant attention in biomedical research as versatile probes for imaging, sensing, and therapies. However, the interactions between proteins and QDs, which are crucial for their use in biological applications, are not yet fully understood. Asymmetric flow field-flow fractionation (AF4) is a promising method for analyzing the interactions of proteins with QDs. This technique uses a combination of hydrodynamic and centrifugal forces to separate and fractionate particles based on their size and shape. By coupling AF4 with other techniques, such as fluorescence spectroscopy and multi-angle light scattering, it is possible to determine the binding affinity and stoichiometry of protein-QD interactions. Herein, this approach has been utilized to determine the interaction between fetal bovine serum (FBS) and silicon quantum dots (SiQDs). Unlike metal-containing conventional QDs, SiQDs are highly biocompatible and photostable in nature, making them attractive for a wide range of biomedical applications. In this study, AF4 has provided crucial information on the size and shape of the FBS/SiQD complexes, their elution profile, and their interaction with serum components in real time. The differential scanning microcalorimetric technique has also been employed to monitor the thermodynamic behavior of proteins in the presence of SiQDs. We have investigated their binding mechanisms by incubating them at temperatures below and above the protein denaturation. This study yields various significant characteristics such as their hydrodynamic radius, size distribution, and conformational behavior. The compositions of SiQD and FBS influence the size distribution of their bioconjugates; the size increases by intensifying the concentration of FBS, with their hydrodynamic radii ranging between 150 and 300 nm. The results signify that in the alliance of SiQDs to the system, there is an augmentation of the denaturation point of the proteins and hence their thermal stability, providing a more comprehensive understanding of the interactions between FBS and QDs.


Assuntos
Fracionamento por Campo e Fluxo , Pontos Quânticos , Pontos Quânticos/química , Silício , Soroalbumina Bovina/química , Fracionamento por Campo e Fluxo/métodos , Temperatura
4.
J Am Chem Soc ; 144(24): 10830-10843, 2022 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-35587544

RESUMO

Chromophores that generate singlet oxygen (1O2) in water are essential to developing noninvasive disease treatments using photodynamic therapy (PDT). A facile approach for formation of stable colloidal nanoparticles of 1O2 photosensitizers, which exhibit aggregation enhanced 1O2 generation in water toward applications as PDT agents, is reported. Chromophore encryption within a fuchsonarene macrocyclic scaffold insulates the photosensitizer from aggregation induced deactivation pathways, enabling a higher chromophore density than typical 1O2 generating nanoparticles. Aggregation enhanced 1O2 generation in water is observed, and variation in molecular structure allows for regulation of the physical properties of the nanoparticles which ultimately affects the 1O2 generation. In vitro activity and the ability of the particles to pass through the cell membrane into the cytoplasm is demonstrated using confocal fluorescence microscopy with HeLa cells. Photosensitizer encryption in rigid macrocycles, such as fuchsonarenes, offers new prospects for the production of biocompatible nanoarchitectures for applications involving 1O2 generation.


Assuntos
Fotoquimioterapia , Fármacos Fotossensibilizantes , Células HeLa , Humanos , Oxigênio , Fármacos Fotossensibilizantes/química , Oxigênio Singlete/metabolismo , Água
5.
Biotechnol Bioeng ; 119(4): 1157-1163, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35067921

RESUMO

Cobalt-chromium-molybdenum (CCM) alloys possess high corrosion-resistant properties as well as good mechanical properties. Hence, the alloys are employed in medical implants such as artificial knee and hip joints, coronary stents, and removable partial dentures. To improve the biocompatibility of CCM alloys, we reported that CCM-binding peptide (CBP) linked to cell-adhesive motif Arg-Gly-Asp (RGD) improved the attachment of endothelial cells on CCM alloys. However, the stability of CBP adsorption on the alloy and its effect on osteoblast compatibility are still unclear. In this study, we evaluated the stabilization of the adsorption layer of CBP-RGD on CCM alloy surface and investigated the effect of CBP-RGD peptide on the proliferation and differentiation of the osteoblasts. CBP-RGD layer exhibited higher stabilization than the RGD adsorption layer for 7 days. In addition, the proliferation of osteoblast on CBP-RGD adsorbed alloy higher than that on RGD adsorbed alloy. Moreover, the calcification of cells cultured on the CBP-RGD adsorbed alloy was significantly higher than that of the cells on RGD adsorbed alloy. These findings indicate that the CBP binding was stable during the culture of osteoblasts on the CCM alloy.


Assuntos
Ligas , Células Endoteliais , Ligas/química , Proliferação de Células , Teste de Materiais , Osteoblastos , Peptídeos , Propriedades de Superfície , Vitálio/química
6.
Langmuir ; 38(17): 5188-5196, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35083914

RESUMO

We report carboxy-terminated silicon quantum dots (SiQDs) that exhibit high solubility in water due to the high molecular coverage of surface monolayers, bright light emission with high photoluminescence quantum yields (PLQYs), long-term stability in the PL property for monitoring cells, less toxicity to the cells, and a high photothermal response. We prepared water-soluble SiQDs by the thermal hydrosilylation of 10-undecenoic acid on their hydrogen-terminated surfaces, provided by the thermal disproportionation of triethoxysilane hydrolyzed at pH 3 and subsequent hydrofluoric etching. The 10-undecanoic acid-functionalized SiQDs (UA:SiQDs) showed long-term stability in hydrophilic solvents including ethanol and water (pH 7). We assess their interaction with live cells by means of cellular uptake, short-term toxicity, and, for the first time, long-term cytotoxicity. Results show that UA:SiQDs are potential candidates for theranostics, with their good optical properties enabling imaging for more than 18 days and a photothermal response having a 25.1% photothermal conversion efficiency together with the direct evidence of cell death by laser irradiation. UA:SiQDs have low cytotoxicity with full viability of up to 400 µg/mL for the short term and a 50% cell viability value after 14 days of incubation at a 50 µg/mL concentration.


Assuntos
Pontos Quânticos , Silício , Fluorescência , Hidrogênio , Pontos Quânticos/química , Pontos Quânticos/toxicidade , Silício/química , Água
7.
Biomacromolecules ; 23(3): 1101-1111, 2022 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35104113

RESUMO

In this study, concentrated polymer brush-modified cellulose nanofibers (CNFs) with different fiber lengths were used for the flocculation of cells for systematically studying the mechanism of this unique cellular flocculation based on colloidal flocculation theory. Concentrated poly(p-styrenesulfonic acid sodium salt) brush-grafted CNF (CNF-PSSNa) with different fiber lengths were cultured with three different cell types to examine their influence on floc (cell clusters formed by cellular flocculation) characteristics. The floc size and survival rate could be controlled by modifying the CNF-PSSNa fiber lengths. The three cell types showed the same flocculation tendency after culture, indicating the applicability of the method in different cell lines. After 2 weeks of culture, CNF-PSSNa increased the specific expression of hepatocytes compared to the two-dimensional cell culture. Thus, owing to its wide applicability, high cell viability, and ability to control cell size and improve cell function, this technology could be used as a new three-dimensional cell culture method.


Assuntos
Nanofibras , Celulose , Floculação , Polímeros
8.
Nanomedicine ; 40: 102508, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34906721

RESUMO

Guanine-quadruplex (G4) oligodeoxynucleotides (ODNs) that contain unmethylated cytosine-phosphate-guanine motifs (G4 CpG ODN) with phosphodiester backbones are safer than the phosphorothioate (PT)-modified CpG ODNs recently used as vaccine adjuvants. However, cellular uptake and the nuclease stability of G4 CpG ODNs are still insufficient, resulting in lower immunostimulatory activity than PT-modified CpG ODNs. We aimed to enhance the immunostimulatory properties of G4 CpG ODNs by complexing with the cationic liposome 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP). The complex acquired nuclease resistance and improved cellular uptake. The immunostimulatory activity of the G4 CpG ODN-DOTAP lipoplexes was enhanced to a level comparable to that of PT-modified ODNs. In addition, the lipoplexes based on unmodified G4 CpG ODNs demonstrated CpG motif-specific immunostimulant activity, although PT-modified ODNs lacking the CpG motif could activate human immune cells. Interestingly, G4 CpG ODN-DOTAP lipoplexes induced interferon-α production in a loop-length dependent manner.


Assuntos
Oligodesoxirribonucleotídeos , Propano , Adjuvantes Imunológicos/farmacologia , Ilhas de CpG , Ácidos Graxos Monoinsaturados , Humanos , Oligodesoxirribonucleotídeos/farmacologia , Compostos de Amônio Quaternário/farmacologia
9.
Int J Mol Sci ; 23(3)2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35162963

RESUMO

After dental implantation, osteopontin (OPN) is deposited on the hydroxyapatite (HA) blasted implant surface followed by direct osteogenesis, which is significantly disturbed in Opn-knockout (KO) mice. However, whether applying OPN on the implant surface promotes direct osteogenesis remains unclarified. This study analyzed the effects of various OPN modified protein/peptides coatings on the healing patterns of the bone-implant interface after immediately placed implantation in the maxilla of four-week-old Opn-KO and wild-type (WT) mice (n = 96). The decalcified samples were processed for immunohistochemistry for OPN and Ki67 and tartrate-resistant acid phosphatase histochemistry. In the WT mice, the proliferative activity in the HA binding peptide-OPN mimic peptide fusion coated group was significantly higher than that in the control group from day 3 to week 1, and the rates of OPN deposition and direct osteogenesis around the implant surface significantly increased in the recombinant-mouse-OPN (rOPN) group compared to the Gly-Arg-Gly-Asp-Ser peptide group in week 2. The rOPN group achieved the same rates of direct osteogenesis and osseointegration as those in the control group in a half period (week 2). None of the implant surfaces could rescue the direct osteogenesis in the healing process in the Opn-KO mice. These results suggest that the rOPN coated implant enhances direct osteogenesis during osseointegration following implantation.


Assuntos
Durapatita/química , Osseointegração/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteopontina/administração & dosagem , Fosfatase Ácida/metabolismo , Animais , Implantação Dentária , Implantes Dentários , Técnicas de Inativação de Genes , Camundongos , Modelos Animais , Osteopontina/química , Osteopontina/genética , Osteopontina/farmacologia , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia
10.
Biomacromolecules ; 22(6): 2505-2514, 2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-33938735

RESUMO

Concentrated polymer brushes (CPBs) are known to suppress biofouling phenomena, such as protein adsorption and cell adhesion. However, a cumbersome process is needed for their synthesis. Here, we report a simple and versatile method for fabricating nonbiofouling coatings that uses well-defined bottlebrushes instead of CPBs. First, a macroinitiator, poly[2-(2-bromoisobutyryloxy)ethyl methacrylate] (PBIEM), was synthesized by reversible addition-fragmentation chain transfer polymerization. Then, poly[poly(ethylene glycol) methyl ether methacrylate] was grafted from PBIEM through atom transfer radical polymerization to form well-defined bottlebrushes. By controlling the graft chain length, two types of bottlebrushes could be prepared, namely those with a semi-dilute polymer brush (SDPB) structure or a CPB structure on the surface of the outermost layer. Crosslinked films of the bottlebrushes were prepared on silicon wafers by spin-coating and subsequent radical coupling. Importantly, the CPB-type bottlebrush films showed significantly better nonbiofouling characteristics than those of the SDPB-type bottlebrush films.


Assuntos
Incrustação Biológica , Polímeros , Adsorção , Incrustação Biológica/prevenção & controle , Adesão Celular , Metacrilatos , Polimerização , Propriedades de Superfície
11.
Biomacromolecules ; 21(9): 3644-3657, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32857497

RESUMO

Synthetic oligodeoxynucleotides (ODNs) containing unmethylated cytosine-phosphate-guanine (CpG) motifs trigger the immune response by stimulating endosomal Toll-like receptor (TLR) 9. Natural linear ODNs are susceptible to nuclease degradation, thereby limiting their clinical applications. Here, we designed monomeric G-quadruplex-based CpG ODNs (G4 CpG ODNs) containing CpG motifs in the central loop region of the G4 structure. The monomeric G4 CpG ODNs were more stable in serum than the linear ODNs. The monomeric G4 CpG ODNs containing two or three CpG motifs induced the production of immunostimulatory cytokines interleukin (IL)-6, IL-12, and interferon (IFN)-ß in mouse macrophage-like RAW264 cells. We also showed that the number of CpG motifs and the number of nucleotides between the CpG motif and G-tracts define the efficacy of the G4 CpG ODNs in activating TLR9. Incubating human peripheral blood mononuclear cells with G4 CpG ODNs promoted IL-6 and IFN-γ production, confirming their stimulatory effects on human immune cells. Mice given intraperitoneal injections of G4 CpG ODNs produced higher plasma IL-6 compared with injections of linear ODNs. These findings provide further understanding of the parameters governing the immunostimulatory activity of G4 CpG ODNs, thereby providing insights into the rational design of highly potent G4 CpG ODNs for vaccine adjuvants.


Assuntos
Oligodesoxirribonucleotídeos , Receptor Toll-Like 9 , Adjuvantes Imunológicos/farmacologia , Animais , Ilhas de CpG , Citosina , Guanina , Leucócitos Mononucleares/metabolismo , Camundongos , Fosfatos , Receptor Toll-Like 9/metabolismo
12.
Biotechnol Lett ; 42(5): 747-756, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32040673

RESUMO

OBJECTIVES: Improving biocompatibility of metallic alloy biomaterials has been of great interest to prevent implant associated-diseases, such as stent thrombosis. Herein a simple and efficient procedure was designed to biofunctionalize a biomaterial surface by isolating a SUS316L stainless steel binding peptide. RESULTS: After three rounds of phage panning procedure, 12 mer peptide (SBP-A; VQHNTKYSVVIR) was identified as SUS316L-binding peptide. The SBP-A peptide formed a stable bond to a SUS316L modified surface and was not toxic to HUVECs. The SBP-A was then used for anti-ICAM antibody modification on SUS316L to construct a vascular endothelial cell-selective surface. The constructed surface dominantly immobilized vascular endothelial cells to smooth muscle cells, demonstrating that the SBP-A enabled simple immobilization of biomolecules without disturbing their active biological function. CONCLUSIONS: The SUS316L surface was successfully biofunctionalized using the novel isolated peptide SBP-A, showing its potential as an ideal interface molecule for stent modification. This is the first report of material binding peptide-based optimal surface functionalization to promote endothelialisation. This simple and efficient biofunctionalization procedure is expected to contribute to the development of biocompatible materials.


Assuntos
Materiais Biocompatíveis/química , Ferro/química , Peptídeos/química , Ligas/química , Anticorpos/química , Materiais Biocompatíveis/farmacologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Teste de Materiais , Especificidade de Órgãos , Biblioteca de Peptídeos , Peptídeos/farmacologia , Aço Inoxidável/química , Propriedades de Superfície
13.
Sci Technol Adv Mater ; 21(1): 346-358, 2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32939160

RESUMO

Corrosion-control coatings which can enhance bone formation and be completely replaced by bone are attractive for biodegradable Mg alloys. Carbonate apatite (CAp) and hydroxyapatite (HAp) coatings were formed on Mg-4 wt% Y-3 wt% rare earth (WE43) alloy as a corrosion-control and bioabsorbable coating in the coating solution with various concentrations of NaHCO3. The incorporation of carbonate group in apatite structure was examined using X-ray diffraction and Fourier transform infrared spectroscopy. Rat osteoclast precursor and MC3T3-E1 osteoblast cells were cultured on the CAp- and HAp-coated WE43 to examine the osteoclastic resorption and the alkaline phosphatase (ALP) activity, respectively. Mg ions in the used medium were quantified to examine the corrosion-control ability. The NaHCO3 addition in the solution resulted in the formation of B-type CAp in which the phosphate group of apatite structure was substituted with the carbonate group. The osteoclastic resorption was observed only for the CAp coatings as the cracking of the coatings and the corrosion of substrate WE43 strongly localized under osteoclast cell bodies. The CAp and HAp coatings significantly enhanced the ALP activity of osteoblasts. The CAp-coated WE43 specimens showed 1/5 smaller amount of Mg ion release than the uncoated WE43 on the first day of culturing osteoblasts. For the subsequent 22 days, the Mg ion release was reduced to 1/2 by the CAp coatings. In the presence of osteoclasts, the CAp coatings showed slightly lower corrosion protectiveness than the HAp coating. It was demonstrated that the CAp coatings can be a bioabsorbable and corrosion-control coating for biodegradable Mg alloys.

14.
Sci Technol Adv Mater ; 18(1): 96-109, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28179963

RESUMO

Octacalcium phosphate (OCP) and hydroxyapatite (HAp) coatings were developed to control the degradation speed and to improve the biocompatibility of biodegradable magnesium alloys. Osteoblast MG-63 was cultured directly on OCP- and HAp-coated Mg-3Al-1Zn (wt%, AZ31) alloy (OCP- and HAp-AZ31) to evaluate cell compatibility. Cell proliferation was remarkably improved with OCP and HAp coatings which reduced the corrosion and prevented the H2O2 generation on Mg alloy substrate. OCP-AZ31 showed sparse distribution of living cell colonies and dead cells. HAp-AZ31 showed dense and homogeneous distribution of living cells, with dead cells localized over and around corrosion pits, some of which were formed underneath the coating. These results demonstrated that cells were dead due to changes in the local environment, and it is necessary to evaluate the local biocompatibility of magnesium alloys. Cell density on HAp-AZ31 was higher than that on OCP-AZ31 although there was not a significant difference in the amount of Mg ions released in medium between OCP- and HAp-AZ31. The outer layer of OCP and HAp coatings consisted of plate-like crystal with a thickness of around 0.1 µm and rod-like crystals with a diameter of around 0.1 µm, respectively, which grew from a continuous inner layer. Osteoblasts formed focal contacts on the tips of plate-like OCP and rod-like HAp crystals, with heights of 2-5 µm. The spacing between OCP tips of 0.8-1.1 µm was wider than that between HAp tips of 0.2-0.3 µm. These results demonstrated that cell proliferation depended on the micromorphology of the coatings which governed spacing of focal contacts. Consequently, HAp coating is suitable for improving cell compatibility and bone-forming ability of the Mg alloy.

15.
Langmuir ; 31(4): 1312-9, 2015 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-25575280

RESUMO

Supported lipid bilayers (SLBs) are often formed by spontaneous vesicle rupture and fusion on a solid surface. A well-characterized rupture mechanism for isolated vesicles is pore nucleation and expansion in the solution-exposed nonadsorbed area. In contrast, pore formation in the adsorbed bilayer region has not been investigated to date. In this work, we studied the detailed mechanisms of asymmetric rupture of giant unilamellar vesicles (GUVs) adsorbed on glass using fluorescence microscopy. Asymmetric rupture is the pathway where a rupture pore forms in a GUV near the edge of the glass-bilayer interface with high curvature and then expansion of the pore yields a planar bilayer patch. We show that asymmetric rupture occasionally resulted in SLB patches bearing a defect pore. The defect formation probability depended on lipid composition, salt concentration, and pH. Approximately 40% of negatively charged GUVs under physiological conditions formed pore-containing SLB patches, while negatively charged GUVs at low salt concentration or pH 4.0 and positively charged GUVs exhibited a low probability of defect inclusion. The edge of the defect pore was either in contact with (on-edge) or away from (off-edge) the edge of the planar bilayer. On-edge pores were predominantly formed over off-edge defects. Pores initially formed in the glass-adsorbed region before rupture, most frequently in close contact with the edge of the adsorbed region. When a pore formed near the edge of the adsorbed area or when the edge of a pore reached that of the adsorbed area by pore expansion, asymmetric rupture was induced from the defect site. These induced rupture mechanisms yielded SLB patches with an on-edge pore. In contrast, off-edge pores were produced when defect pore generation and subsequent vesicle rupture were uncoupled. The current results demonstrate that pore formation in the surface-adsorbed region of GUVs is not a negligible event.


Assuntos
Vidro , Bicamadas Lipídicas/química , Concentração de Íons de Hidrogênio , Microscopia de Fluorescência , Propriedades de Superfície
16.
Phys Chem Chem Phys ; 17(38): 25455-62, 2015 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-26365825

RESUMO

Gene delivery is often accomplished by the forward or reverse transfection protocol. In either protocol, a transfection reagent (usually cationic) is added to increase the delivery efficiency. In this study, we employed a series of nanosheet networks to facilitate the delivery of naked plasmid DNA into human mesenchymal stem cells (hMSCs). By adding different chemicals into the reaction mixture for etching the silica glass, we were able to fabricate inorganic/organic hybrid nanosheet networks with different physico-chemical characteristics. We then analyzed the transfection efficiency on different nanosheets and the possible dependence of the transfection efficiency on the physico-chemical parameters of nanosheets. The results showed that all nanosheet networks were noncytotoxic and demonstrated a high cell survival rate (∼90%) after transfection. The transfection efficiency was critically determined by the aspect ratio (height/thickness of the wall) of the nanosheets. The effects of chemistry or other surface properties were not significant. Moreover, the transfection efficiency may be successfully predicted by the initial cell migration rate and the activation of integrin ß3 on the nanosheets. Compared to the conventional method, transfection using concurrent cell/plasmid seeding on the nanosheets is not only more effective but also much safer. Future efforts may focus on combining the inorganic/organic hybrid nanosheets with soft substrates for in situ transfection.


Assuntos
Nanoestruturas/química , Dióxido de Silício/química , Transfecção , Movimento Celular , Sobrevivência Celular , Células Cultivadas , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Plasmídeos/genética , Plasmídeos/metabolismo , Propriedades de Superfície
17.
J Am Chem Soc ; 136(4): 1194-7, 2014 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-24410250

RESUMO

We describe a novel epitope discovery strategy for creating an affinity agent/peptide tag pair. A synthetic polymer nanoparticle (NP) was used as the "bait" to catch an affinity peptide tag. Biotinylated peptide tag candidates of varied sequence and length were attached to an avidin platform and screened for affinity against the polymer NP. NP affinity for the avidin/peptide tag complexes was used to provide insight into factors that contribute NP/tag binding. The identified epitope sequence with an optimized length (tMel-tag) was fused to two recombinant proteins. The tagged proteins exhibited higher NP affinity than proteins without tags. The results establish that a fusion peptide tag consisting of optimized 15 amino acid residues can provide strong affinity to an abiotic polymer NP. The affinity and selectivity of NP/tMel-tag interactions were exploited for protein purification in conjunction with immobilized metal ion/His6-tag interactions to prepare highly purified recombinant proteins. This strategy makes available inexpensive, abiotic synthetic polymers as affinity agents for peptide tags and provides alternatives for important applications where more costly affinity agents are used.


Assuntos
Epitopos/química , Nanopartículas/química , Peptídeos/química , Polímeros/síntese química , Avidina/química , Estrutura Molecular , Tamanho da Partícula , Polímeros/química , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Propriedades de Superfície
18.
Biomolecules ; 14(8)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39199319

RESUMO

Synthetic oligodeoxynucleotides (ODNs) containing unmethylated cytosine-phosphate-guanine (CpG) motifs (CpG-ODNs) are ligand molecules for Toll-like receptor 9 (TLR9), which is expressed by odontoblasts in vitro and dental pulp cells. This study determined the effects of CpG-ODNs on pulpal immunomodulatory response and repair following injury. Briefly, the upper right first molars of three-week-old mice were extracted, immersed in Type A (D35) or B (K3) CpG-ODN solutions (0.1 or 0.8 mM) for 30 min, and then replanted. Pulpal healing and immunomodulatory activity were assessed by hematoxylin-eosin and AZAN staining, as well as immunohistochemistry. One week following the operation, inflammatory reactions occurred in all of the experimental groups; however, re-revascularization and newly formed hard tissue deposition were observed in the pulp chamber of all groups at week 2. A positive trend in the expression of immune cell markers was observed toward the CpG-ODN groups at 0.1 mM. Our data suggest that synthetic CpG-ODN solutions at low concentrations may evoke a long-lasting macrophage-TLR9-mediated pro-inflammatory, rather than anti-inflammatory, response in the dental pulp to modulate the repair process and hard tissue formation. Further studies are needed to determine the effects of current immunomodulatory agents in vitro and in vivo and develop treatment strategies for dental tissue regeneration.


Assuntos
Polpa Dentária , Oligodesoxirribonucleotídeos , Receptor Toll-Like 9 , Animais , Camundongos , Oligodesoxirribonucleotídeos/farmacologia , Receptor Toll-Like 9/metabolismo , Polpa Dentária/efeitos dos fármacos , Polpa Dentária/citologia , Ligantes , Cicatrização/efeitos dos fármacos , Masculino , Imunomodulação/efeitos dos fármacos
19.
Vaccines (Basel) ; 12(6)2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38932378

RESUMO

Oligodeoxynucleotides (ODNs) containing unmethylated cytosine-phosphate-guanosine (CpG) motifs are readily recognized by Toll-like receptor 9 on immune cells, trigger an immunomodulatory cascade, induce a Th1 -biased immune milieu, and have great potential as an adjuvant in cancer vaccines. In this study, a green one-step synthesis process was adopted to prepare an amino-rich metal-organic nanoplatform (FN). The synthesized FN nanoplatform can simultaneously and effectively load model tumor antigens (OVA)/autologous tumor antigens (dLLC) and immunostimulatory CpG ODNs with an unmodified PD backbone and a guanine quadruplex structure to obtain various cancer vaccines. The FN nanoplatform and immunostimulatory CpG ODNs generate synergistic effects to enhance the immunogenicity of different antigens and inhibit the growth of established and distant tumors in both the murine E.G7-OVA lymphoma model and the murine Lewis lung carcinoma model. In the E.G7-OVA lymphoma model, vaccination efficiently increases the CD4+, CD8+, and tetramer+CD8+ T cell populations in the spleens. In the Lewis lung carcinoma model, vaccination efficiently increases the CD3+CD4+ and CD3+CD8+ T cell populations in the spleens and CD3+CD8+, CD3-CD8+, and CD11b+CD80+ cell populations in the tumors, suggesting the alteration of tumor microenvironments from cold to hot tumors.

20.
Tuberculosis (Edinb) ; 146: 102498, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38461765

RESUMO

Drug resistance to tuberculosis (TB) has become an obstacle in eliminating tuberculosis. The transmission of drug-resistant TB from patients increases the incidence of primary drug-resistant (DR) TB in individuals who are in close contact. Therefore, it is necessary to incorporate an immunological approach into preventive therapy. This study focuses on the activity of lysosomal enzymes, oxygen bursts, and the attachment ability of macrophages among individuals diagnosed with active drug-resistant TB compared with close contacts with latent TB or healthy cases. We measured macrophage oxygen burst ability (Water-soluble tetrazolium salt (WST) test, Nitric Oxide production, and myeloperoxidase activity) and the degradative ability of lysosomes (activity of the ß-glucuronidase and acid phosphatase enzymes). Six active DR-TB patients and 18 close-contact cases (8 Latent Tuberculosis Infection (LTBI); 10 healthy) were recruited at Universitas Indonesia Hospital. The macrophage attachment of the LTBI group was higher than in the other groups. NO production, myeloperoxidase activity, ß-glucuronidase, and acid phosphatase were higher in the active DR-TB group. A negative correlation was uncovered between phagocytosis and NO production, myeloperoxidase activity, and lysosomal enzymes. The difference in macrophage function is expected to be a further reference in active DR-TB treatment or preventive therapy.


Assuntos
Tuberculose Latente , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose , Humanos , Tuberculose/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Macrófagos , Glucuronidase , Óxido Nítrico , Fosfatase Ácida , Peroxidase
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