Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Adv Mater ; 33(40): e2101558, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34431568

RESUMO

Cell-cell interactions regulate intracellular signaling via reciprocal contacts of cell membranes in tissue regeneration and cancer growth, indicating a critical need of membrane-derived tools in studying these processes. Hence, cell-membrane-derived nanoparticles (CMNPs) are produced using tonsil-derived mesenchymal stem cells (TMSCs) from children owing to their short doubling time. As target cell types, laryngeal cancer cells are compared to bone-marrow-derived MSCs (BMSCs) because of their cartilage damaging and chondrogenic characteristics, respectively. Treating spheroids of these cell types with CMNPs exacerbates interspheroid hypoxia with robust maintenance of the cell-cell interaction signature for 7 days. Both cell types prefer a hypoxic environment, as opposed to blood vessel formation that is absent in cartilage but is required for cancer growth. Hence, angiogenesis is inhibited by displaying the Notch-1 aptamer on CMNPs. Consequently, laryngeal cancer growth is suppressed efficiently in contrast to improved chondroprotection observed in a series of cell and animal experiments using a xenograft mouse model of laryngeal cancer. Altogether, CMNPs execute a two-edged sword function of inducing hypoxic cell-cell packing, followed by suppressing angiogenesis to promote laryngeal cancer death and chondrogenesis simultaneously. This study presents a previously unexplored therapeutic strategy for anti-cancer and chondroprotective treatment using CMNPs.


Assuntos
Membrana Celular/química , Nanopartículas/química , Receptor Notch1/química , Animais , Caderinas/metabolismo , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Condrócitos/citologia , Portadores de Fármacos/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Nanopartículas/uso terapêutico , Nanopartículas/toxicidade , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Neovascularização Fisiológica/efeitos dos fármacos , Tonsila Palatina/citologia , Receptor Notch1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transplante Heterólogo
2.
Small ; 16(16): e2000012, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32239653

RESUMO

Atherosclerosis development leads to irreversible cascades, highlighting the unmet need for improved methods of early diagnosis and prevention. Disturbed flow formation is one of the earliest atherogenic events, resulting in increased endothelial permeability and subsequent monocyte recruitment. Here, a mesenchymal stem cell (MSC)-derived nanovesicle (NV) that can target disturbed flow sites with the peptide GSPREYTSYMPH (PREY) (PMSC-NVs) is presented which is selected through phage display screening of a hundred million peptides. The PMSC-NVs are effectively produced from human MSCs (hMSCs) using plasmid DNA designed to functionalize the cell membrane with PREY. The potent anti-inflammatory and pro-endothelial recovery effects are confirmed, similar to those of hMSCs, employing mouse and porcine partial carotid artery ligation models as well as a microfluidic disturbed flow model with human carotid artery-derived endothelial cells. This nanoscale platform is expected to contribute to the development of new theragnostic strategies for preventing the progression of atherosclerosis.


Assuntos
Aterosclerose/terapia , Células-Tronco Mesenquimais , Nanopartículas , Animais , Artérias Carótidas , Células Endoteliais , Humanos , Ligadura , Camundongos , Suínos
3.
Sci Adv ; 6(9): eaay5413, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32133403

RESUMO

Angiogenesis is stimulated by nitric oxide (NO) production in endothelial cells (ECs). Although proangiogenic actions of human mesenchymal stem cells (hMSCs) have been extensively studied, the mechanistic role of NO in this action remains obscure. Here, we used a gelatin hydrogel that releases NO upon crosslinking by a transglutaminase reaction ("NO gel"). Then, the source-specific behaviors of bone marrow versus adipose tissue-derived hMSCs (BMSCs versus ADSCs) were monitored in the NO gels. NO inhibition resulted in significant decreases in their angiogenic activities. The NO gel induced pericyte-like characteristics in BMSCs in contrast to EC differentiation in ADSCs, as evidenced by tube stabilization versus tube formation, 3D colocalization versus 2D coformation with EC tube networks, pericyte-like wound healing versus EC-like vasculogenesis in gel plugs, and pericyte versus EC marker production. These results provide previously unidentified insights into the effects of NO in regulating hMSC source-specific angiogenic mechanisms and their therapeutic applications.


Assuntos
Tecido Adiposo/metabolismo , Células da Medula Óssea/metabolismo , Hidrogéis , Células-Tronco Mesenquimais/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Óxido Nítrico , Tecido Adiposo/citologia , Antígenos de Diferenciação/metabolismo , Células da Medula Óssea/citologia , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Gelatina/química , Gelatina/farmacologia , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Células-Tronco Mesenquimais/citologia , Óxido Nítrico/química , Óxido Nítrico/farmacologia
4.
Nat Commun ; 11(1): 615, 2020 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-32001693

RESUMO

Angiogenesis induction into damaged sites has long been an unresolved issue. Local treatment with pro-angiogenic molecules has been the most common approach. However, this approach has critical side effects including inflammatory coupling, tumorous vascular activation, and off-target circulation. Here, the concept that a structure can guide desirable biological function is applied to physically engineer three-dimensional channel networks in implant sites, without any therapeutic treatment. Microchannel networks are generated in a gelatin hydrogel to overcome the diffusion limit of nutrients and oxygen three-dimensionally. Hydrogel implantation in mouse and porcine models of hindlimb ischemia rescues severely damaged tissues by the ingrowth of neighboring host vessels with microchannel perfusion. This effect is guided by microchannel size-specific regenerative macrophage polarization with the consequent functional recovery of endothelial cells. Multiple-site implantation reveals hypoxia and neighboring vessels as major causative factors of the beneficial function. This technique may contribute to the development of therapeutics for hypoxia/inflammatory-related diseases.


Assuntos
Indutores da Angiogênese/efeitos adversos , Gelatina/química , Gelatina/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Isquemia/terapia , Animais , Modelos Animais de Doenças , Células Endoteliais/patologia , Desenho de Equipamento , Feminino , Membro Posterior/irrigação sanguínea , Membro Posterior/diagnóstico por imagem , Membro Posterior/patologia , Hidrogéis/uso terapêutico , Hipóxia , Isquemia/diagnóstico por imagem , Isquemia/patologia , Macrófagos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Neovascularização Fisiológica/fisiologia , Doenças Vasculares Periféricas/patologia , Doenças Vasculares Periféricas/terapia , Próteses e Implantes , Suínos , Cicatrização
5.
Adv Healthc Mater ; 9(5): e1901612, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31977158

RESUMO

Osteoarthritis (OA) is a painful intractable disease that significantly affects patients' quality of life. However, current therapies, such as pain killers and joint replacement surgery, do not lead to cartilage protection. Mesenchymal stem cells (MSCs) have been proposed as an alternative strategy for OA therapy because MSCs can secrete chondroprotective and anti-inflammatory factors. However, interleukin-4 (IL-4), a potent anti-inflammatory cytokine, is barely produced by MSCs, and MSC therapy suffers from rapid MSC death following intra-articular implantation. MSCs in spheroids survive better than naïve MSCs in vitro and in vivo. IL-4-transfected MSCs in spheroids (IL-4 MSC spheroid) show increased chondroprotective and anti-inflammatory effects in an OA chondrocyte model in vitro. Following intra-articular implantation in OA rats, IL-4 MSC spheroids show better cartilage protection and pain relief than naïve MSCs. Thus, IL-4 MSC spheroid may potentiate the therapeutic efficacy of MSCs for OA.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Osteoartrite , Animais , Humanos , Injeções Intra-Articulares , Interleucina-4 , Osteoartrite/terapia , Qualidade de Vida , Ratos , Transfecção
6.
J Vis Exp ; (139)2018 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-30320742

RESUMO

Live models that resemble surgical conditions of humans are needed for training free-flap harvesting and anastomosis. Animal models for training purposes have been available for years in many surgical fields. We used the female (because they are easy to handle for the procedure) Yorkshire pigs for the head and neck reconstruction by harvesting the deep inferior epigastric artery perforator or the superior epigastric artery perforator flap. The anastomosis site (neck skin defect or tracheal wall defect) was prepared via the dissection of the common carotid artery and the internal jugular vein, in which 3.5× loupe magnification was used for anastomosis as we use on human cases in real life. This procedure demonstrates a new training method using a reliable learning model and provides a detailed anatomy in a live scenario. We focused on the ischemia time, harvesting, vessel anastomosis, and designing the flap to fit the defect site. This model improves tissue handling and with the use of proper instruments can be repeated many times so that the surgeon is fully confident before starting the surgery on humans.


Assuntos
Anastomose Cirúrgica/métodos , Cabeça/cirurgia , Pescoço/cirurgia , Animais , Feminino , Humanos , Modelos Animais , Suínos
7.
Int J Mol Sci ; 19(2)2018 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-29370101

RESUMO

Human mesenchymal stem cells (hMSCs) have been widely studied for therapeutic development in tissue engineering and regenerative medicine. They can be harvested from human donors via tissue biopsies, such as bone marrow aspiration, and cultured to reach clinically relevant cell numbers. However, an unmet issue lies in the fact that the hMSC donors for regenerative therapies are more likely to be of advanced age. Their stem cells are not as potent compared to those of young donors, and continue to lose healthy, stemness-related activities when the hMSCs are serially passaged in tissue culture plates. Here, we have developed a cheap, scalable, and effective copolymer film to culture hMSCs obtained from aged human donors over several passages without loss of reactive oxygen species (ROS) handling or differentiation capacity. Assays of cell morphology, reactive oxygen species load, and differentiation potential demonstrate the effectiveness of copolymer culture on reduction in senescence-related activities of aging donor-derived hMSCs that could hinder the therapeutic potential of autologous stem cell therapies.


Assuntos
Envelhecimento/metabolismo , Diferenciação Celular , Células-Tronco Mesenquimais/metabolismo , Cultura Primária de Células/métodos , Espécies Reativas de Oxigênio/metabolismo , Materiais Biocompatíveis/química , Proliferação de Células , Células Cultivadas , Humanos , Células-Tronco Mesenquimais/citologia , Poliésteres , Polietilenoglicóis
8.
Sci Rep ; 7(1): 10022, 2017 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-28855683

RESUMO

Although there are various methods for tracheal reconstruction, such as a simple approximation with suturing and coverage with adjacent soft tissue or muscle, large defects >50% of the tracheal length still present a clinical challenge. Tissue engineering, a recent promising way to possibly resolve this problem, requires a long preparatory period for stem cell seeding on a scaffold and relatively invasive procedures for stem cell harvesting. As an alternative, we used a vascularized myofascial flap for tracheal reconstruction. In four porcine models, the deep inferior epigastric perforator (DIEP) was used in two and the superior epigastric artery perforator (SEAP) in two. Transformation of the surface of the transplanted myofascial flap was analyzed in the airway environment. The flaps failed in the DIEP group due to venous congestion. At 12 weeks postoperatively, none of SEAP group showed any signs of respiratory distress; the inner surface of the implant exhibited stratified squamous epithelium with sparse cilia. In the clinical setting, a patient who underwent a tracheal reconstruction with a vascularized myofascial flap and 2-year follow-up was in good health with no respiratory distress symptoms.


Assuntos
Retalho Miocutâneo/transplante , Retalho Perfurante/transplante , Procedimentos de Cirurgia Plástica/métodos , Complicações Pós-Operatórias/etiologia , Transplante de Tecidos/métodos , Traqueia/cirurgia , Idoso , Animais , Artérias Epigástricas/cirurgia , Feminino , Humanos , Masculino , Retalho Miocutâneo/irrigação sanguínea , Retalho Perfurante/irrigação sanguínea , Suínos
9.
ACS Appl Mater Interfaces ; 9(27): 22994-23006, 2017 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-28621931

RESUMO

Human bone marrow derived mesenchymal stem cells (hMSCs) hold great promise for regenerative medicine due to their multipotent differentiation capacity and immunomodulatory capabilities. Substantial research has elucidated mechanisms by which extracellular cues regulate hMSC fate decisions, but considerably less work has addressed how material properties can be leveraged to maintain undifferentiated stem cells. Here, we show that synthetic culture substrates designed to exhibit moderate cell-repellency promote high stemness and low oxidative stress-two indicators of naïve, healthy stem cells-in commercial and patient-derived hMSCs. Furthermore, the material-mediated effect on cell behavior can be tuned by altering the molar percentage (mol %) and/or chain length of poly(ethylene glycol) (PEG), the repellant block linked to hydrophobic poly(ε-caprolactone) (PCL) in the copolymer backbone. Nano- and angstrom-scale characterization of the cell-material interface reveals that PEG interrupts the adhesive PCL domains in a chain-length-dependent manner; this prevents hMSCs from forming mature focal adhesions and subsequently promotes cell-cell adhesions that require connexin-43. This study is the first to demonstrate that intrinsic properties of synthetic materials can be tuned to regulate the stemness and redox capacity of hMSCs and provides new insight for designing highly scalable, programmable culture platforms for clinical translation.


Assuntos
Células-Tronco Mesenquimais , Diferenciação Celular , Humanos , Oxirredução , Polietilenoglicóis , Medicina Regenerativa
10.
J Tissue Eng Regen Med ; 11(12): 3337-3348, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28198165

RESUMO

Vascular endothelial growth factor (VEGF)-transfected adipose-derived stromal cells (ADSCsVEGF ) were devised to promote bone regeneration and neovascularization of bone marrow stromal cells (BMSCs). ADSCsVEGF were added to BMSCs and cocultured in variable proportions. ADSCsVEGF alone or ADSCsVEGF with BMSCs (BMSCs:ADSCsVEGF ratio of 1:0.025-0.5) induced significantly greater tube formation in human umbilical vein endothelial cells than untransfected ADSCs. The cocultures of BMSCs and ADSCsVEGF at ratios of 1: 0.025-0.1 showed significantly greater osteogenic differentiation and mineralization than BMSCs alone in vitro. Osteogenic markers COL1A1, OCN and BSP were most effectively induced at the BMSC: ADSCVEGF ratio of 1:0.05. Of angiogenesis-related genes, upregulation of cathepsin Z and downregulation of early growth response 1 were observed while two osteogenesis-related genes, osteoactivin and tetranectin, were upregulated in BMSCs/ADSCsVEGF compared to BMSCs/ADSCs. When critical size calvarial defects in rats were implanted with mixture of BMSCs and ADSCsVEGF along with hydroxyapatite/ß-tricalcium phosphate granules, BMSCs and ADSCsVEGF at the ratio of 1:0.05 showed better bone regeneration that BMSCs alone. The cotransplantation of ADSCsVEGF with BMSCs significantly increased neovascularization on the regenerated bone of the repaired defect than BMSCs alone. In conclusion, ADSCsVEGF added in small proportion to BMSCs effectively promote bone regeneration and neovascularization. Copyright © 2017 John Wiley & Sons, Ltd.


Assuntos
Tecido Adiposo/citologia , Regeneração Óssea/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Neovascularização Fisiológica/efeitos dos fármacos , Transfecção , Fator A de Crescimento do Endotélio Vascular/farmacologia , Adulto , Idoso , Fosfatase Alcalina/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Análise por Conglomerados , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Ratos , Crânio/patologia , Células Estromais/citologia , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo
11.
J Cell Biochem ; 118(9): 2896-2908, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28214341

RESUMO

Our previous studies revealed that co-transplantation of bone marrow stem cells (BMSCs) and adipose-derived stem cells (ADSCs) can enhance bone regeneration and angiogenesis. However, it is unclear which genes are involved in the regulation of osteogenesis and/or angiogenesis during the co-culturing of BMSCs and ADSCs. The expression patterns of genes associated with osteogenesis and/or angiogenesis were analyzed in osteogenesis-induced BMSCs and ADSCs using an oligonucleotide microarray. Significant difference in the expression patterns of several genes were identified from hierarchical clustering and analyzed on co-cultured BMSCs and ADSCs. Angiopoietin-2 (ANGPT2) and activin receptor-like kinase-1 were significantly down-regulated in co-culture than culture of either BMSCs or ADSCs, while fibroblast growth factor-9 was significantly up-regulated in co-culture. The effect of ANGPT2 in osteogenesis-induced BMSCs was validated using recombinant protein and siRNA of ANGPT2. Treatment of the ANGPT2 protein significantly increased the expressions of osteogenic makers and the intensity of Alizarin red-S staining in BMSCs. Down-regulation of ANGPT2 significantly decreased the expression of osteogenic makers. The treatment of ANGPT2 protein to BMSCs induced significantly increased tube formation in Transwell-co-cultured human umbilical vein endothelial cells (HUVECs) compared with untreated control. ANGPT2 siRNA transfection showed the opposite effects. These results suggest that the treatment of ANGPT2 in BMSCs increase osteogenesis and angiogenesis in vitro, and that the enhancement of osteogenesis and angiogenesis in the co-cultured BMSCs and ADSCs seems to be mediated by a mechanism that makes the activation of ANGPT2 unnecessary. These observations provide the first evidence for positive regulation of osteogenesis by ANGPT2 in vitro. J. Cell. Biochem. 118: 2896-2908, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Angiopoietina-2/metabolismo , Antígenos de Diferenciação/biossíntese , Células da Medula Óssea/metabolismo , Diferenciação Celular/fisiologia , Osteogênese/fisiologia , Células-Tronco/metabolismo , Angiopoietina-2/genética , Células da Medula Óssea/citologia , Humanos , Células-Tronco/citologia
12.
Acta Biomater ; 39: 65-78, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27155347

RESUMO

UNLABELLED: Dual drug delivery of drugs with different therapeutic effects in a single system is an effective way to treat a disease. One of the main challenges in dual drug delivery is to control the release behavior of each drug independently. In this study, we devised thermo-responsive polymeric nanospheres that can provide simultaneous and independent dual drug delivery in the response to temperature change. The nanospheres based on chitosan oligosaccharide conjugated pluronic F127 grafting carboxyl group were synthesized to deliver kartogenin (KGN) and diclofenac (DCF) in a single system. To achieve the dual drug release, KGN was covalently cross-linked to the outer part of the nanosphere, and DCF was loaded into the inner core of the nanosphere. The nanospheres demonstrated immediate release of DCF and sustained release of KGN, which were independently controlled by temperature change. The nanospheres treated with cold temperature effectively suppressed lipopolysaccharide-induced inflammation in chondrocytes and macrophage-like cells. The nanospheres also induced chondrogenic differentiation of mesenchymal stem cells, which was further enhanced by cold shock treatment. Bioluminescence of the fluorescence-labeled nanospheres was significantly increased after cold treatment in vivo. The nanospheres suppressed the progression of osteoarthritis in treated rats, which was further enhanced by cold treatment. The nanospheres also reduced cyclooxygenase-2 expression in the serum and synovial membrane of treated rats, which were further decreased with cold treatment. These results suggest that the thermo-responsive nanospheres provide dual-function therapeutics possessing anti-inflammatory and chondroprotective effects which can be enhanced by cold treatment. STATEMENT OF SIGNIFICANCE: We developed thermo-responsive nanospheres that can provide a useful dual-function of suppressing the inflammation and promoting chondrogenesis in the treatment of osteoarthritis. For a dual delivery system to be effective, the release behavior of each drug should be independently controlled to optimize their desired therapeutic effects. We employed rapid release of diclofenac for acute anti-inflammatory effects, and sustained release of kartogenin, a newly found molecule, for chondrogenic effects in this polymeric nanospheres. This nanosphere demonstrated immediate release of diclofenac and sustained release of kartogenin, which were independently controlled by temperature change. The effectiveness of this system to subside inflammation and regenerate cartilage in osteoarthritis was successful demonstrated through in vitro and in vivo experiments in this study. We think that this study will add a new concept to current body of knowledge in the field of drug delivery and treatment of osteoarthritis.


Assuntos
Anilidas , Diclofenaco , Portadores de Fármacos , Nanosferas , Osteoartrite/tratamento farmacológico , Ácidos Ftálicos , Anilidas/química , Anilidas/farmacocinética , Anilidas/farmacologia , Diferenciação Celular/efeitos dos fármacos , Quitosana/química , Quitosana/farmacocinética , Quitosana/farmacologia , Condrócitos/metabolismo , Condrócitos/patologia , Diclofenaco/química , Diclofenaco/farmacocinética , Diclofenaco/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacologia , Feminino , Humanos , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/patologia , Pessoa de Meia-Idade , Nanosferas/química , Nanosferas/uso terapêutico , Oligossacarídeos/química , Oligossacarídeos/farmacocinética , Oligossacarídeos/farmacologia , Osteoartrite/metabolismo , Osteoartrite/patologia , Ácidos Ftálicos/química , Ácidos Ftálicos/farmacocinética , Ácidos Ftálicos/farmacologia , Poloxâmero/química , Poloxâmero/farmacocinética
13.
Biomaterials ; 35(37): 9984-9994, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25241157

RESUMO

We developed an intra-articular (IA) drug delivery system to treat osteoarthritis (OA) that consisted of kartogenin conjugated chitosan (CHI-KGN). Kartogenin, which promotes the selective differentiation of mesenchymal stem cells (MSCs) into chondrocytes, was conjugated with low-molecular-weight chitosan (LMWCS) and medium-molecular-weight chitosan (MMWCS) by covalent coupling of kartogenin to each chitosan using an ethyl(dimethylaminopropyl) carbodiimide (EDC)/N-hydroxysuccinimide (NHS) catalyst. Nanoparticles (NPs, 150 ± 39 nm) or microparticles (MPs, 1.8 ± 0.54 µm) were fabricated from kartogenin conjugated-LMWCS and -MMWCS, respectively, by an ionic gelation using tripolyphosphate (TPP). The in vitro release profiles of kartogenin from the particles showed sustained release for 7 weeks. When the effects of the CHI-KGN NPs or CHI-KGN MPs were evaluated on the in vitro chondrogenic differentiation of human bone marrow MSCs (hBMMSCs), the CHI-KGN NPs and CHI-KGN MPs induced higher expression of chondrogenic markers from cultured hBMMSCs than unconjugated kartogenin. In particular, hBMMSCs treated with CHI-KGN NPs exhibited more distinct chondrogenic properties in the long-term pellet cultures than those treated with CHI-KGN MPs. The in vivo therapeutic effects of CHI-KGN NPs or CHI-KGN MPs were investigated using a surgically-induced OA model in rats. The CHI-KGN MPs showed longer retention time in the knee joint than the CHI-KGN NPs after IA injection in OA rats. The rats treated with CHI-KGN NPs or CHI-KGN MPs by IA injection showed much less degenerative changes than untreated control or rats treated with unconjugated kartogenin. In conclusion, CHI-KGN NPs or CHI-KGN MPs can be useful polymer-drug conjugates as an IA drug delivery system to treat OA.


Assuntos
Anilidas/administração & dosagem , Anilidas/farmacologia , Cartilagem/efeitos dos fármacos , Quitosana/química , Condrogênese/efeitos dos fármacos , Nanopartículas/química , Osteoartrite/tratamento farmacológico , Ácidos Ftálicos/administração & dosagem , Ácidos Ftálicos/farmacologia , Idoso , Anilidas/química , Animais , Cartilagem/fisiologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Condrócitos/citologia , Humanos , Injeções Intra-Articulares , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Pessoa de Meia-Idade , Ácidos Ftálicos/química , Ratos , Ratos Sprague-Dawley , Regeneração/efeitos dos fármacos
14.
Int J Mol Sci ; 14(4): 6614-23, 2013 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-23528890

RESUMO

Several studies have demonstrated that basic fibroblast growth factor (bFGF) can induce neural differentiation of mesenchymal stem cells. In this study, we investigated the neural differentiation of muscle-derived stem cells (MDSCs) following treatment with bFGF and ethosuximide, a small molecule used as an anticonvulsant in humans. Stem cells isolated from rat skeletal muscle (rMDSCs) were pre-induced by culturing with 25 ng/mL bFGF for 24 h and then were transferred to a medium supplemented with or without 4 mM ethosuximide. Neuronal differentiation was assessed by immunocytochemical and western blotting analyses of marker expression. Immunocytochemistry of rMDSCs treated with bFGF and ethosuximide identified abundant cells expressing neuronal markers (TuJ1, neuron-specific class III ß-tubulin; NeuN, neuronal nuclear antigen; and NF-MH; neurofilament M and H). Olig2 (oligodendrocyte transcription factor 2)-positive cells were also observed, indicating the presence of oligodendrocyte lineage cells. These findings were substantiated by western blotting analysis of marker proteins. In particular, the expression of NeuN and TuJ1 was significantly higher in rMDSCs treated with ethosuximide and bFGF than in cells stimulated with bFGF alone (NeuN, p < 0.05 and TuJ1, p < 0.001). Expression of the astrocyte marker GFAP (glial fibrillary acidic protein) was not detected in this study. Collectively, the results showed that treatment with bFGF and ethosuximide induced effective transdifferentiation of rMDSCs into cells with a neural-like phenotype. Notably, rMDSCs treated with a combination of bFGF plus ethosuximide showed enhanced differentiation compared with cells treated with bFGF alone, implying that ethosuximide may stimulate neuronal differentiation.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Etossuximida/farmacologia , Fator 2 de Crescimento de Fibroblastos/farmacologia , Músculo Esquelético/citologia , Neurônios/citologia , Células-Tronco/citologia , Animais , Biomarcadores/metabolismo , Morte Celular/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Etossuximida/química , Feminino , Fluorescência , Ratos Endogâmicos F344
15.
J Nanosci Nanotechnol ; 11(5): 4174-81, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21780423

RESUMO

In this study, cysteine was conjugated to the Eudragit to have mucoadhesive and pH-sensitive properties. Pasteurella multocida dermonecrotoxin (PMT) is a major virulence factor as a causative agent of atrophic rhinitis (AR) in swine and, therefore, inactivated P. multocida was used as a candidate vaccine in the current study. PMT-loaded thiolated Eudragit microspheres (TEMS) prepared using W/O/W emulsion-solvent evaporation method were characterized to assess their efficacy in oral vaccination. PMT-loaded TEMS were observed as spherical shapes with smooth surfaces and average particle sizes were 5.2 +/- 0.55 microm. The loading efficiency of PMT in the TEMS was about 75.3%. A significantly higher percentage of PMT from PMT-loaded TEMS was released at pH 7.4 than at pH 1.5. Murine macrophage stimulated with PMT-loaded TEMS facilitated a gradual secretion of tumor necrosis factor-alpha and nitric oxide as immune stimulatory mediators in a time dependent manner, suggesting that the released PMT from PMT-loaded TEMS had immune stimulating activity of AR vaccine in vitro.


Assuntos
Antígenos de Bactérias/administração & dosagem , Toxinas Bacterianas/análise , Concentração de Íons de Hidrogênio , Microesferas , Pasteurella multocida/imunologia , Administração Oral , Antígenos de Bactérias/química , Microscopia Eletrônica de Varredura , Tamanho da Partícula
16.
Res Vet Sci ; 90(2): 329-35, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20591455

RESUMO

Classical swine fever (CSF) is a highly contagious disease of pigs that causes fever, diarrhea and paralysis, often resulting in death. E2 is the major structural protein of the CSF virus (CSFV) and mediates the entrance of the virus, subsequently inducing a neutralizing immune response. In this study, the E2 gene of a recent Korean isolate of CSF, SW03, was cloned and the DNA sequence was compared to other strains via phylogenetic analysis. With the purified E2 protein, an enzyme-linked immunosorbent assay (ELISA) was developed for the serodiagnosis of CSFV infection. The sensitivity and specificity of the E2-ELISA were 96.1% and 94.8%, respectively. A total of 17 out of 485 field-collected pig sera tested demonstrated conflicting results between two ELISA methods, a commercial kit and the E2-ELISA. Of these sera, 60% were determined to be CSFV positive by a virus neutralization test (VNT), suggesting involvement of different immune responses in the cases of CSFV infection. As the E2-ELISA was developed using a recent Korean isolate, SW03, this assay is capable of rapidly identifying newly emerging CSFV strains.


Assuntos
Vírus da Febre Suína Clássica/genética , Peste Suína Clássica/virologia , Proteínas Recombinantes/genética , Proteínas do Envelope Viral/genética , Animais , Peste Suína Clássica/sangue , Peste Suína Clássica/epidemiologia , Clonagem Molecular , DNA Complementar/genética , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/veterinária , Filogenia , RNA Viral/genética , Sensibilidade e Especificidade , Testes Sorológicos , Suínos
17.
Biomaterials ; 29(12): 1931-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18221992

RESUMO

A vaccine delivery system based on mannosylated chitosan microspheres (MCMs) was studied in vitro and in vivo. Bordetella bronchiseptica antigens containing dermonecrotoxin (BBD) were loaded in MCMs or chitosan microspheres (CMs). Fluorescence confocal microscopy indicated that BBD-loaded MCMs (BBD-MCMs) bound with mannose receptors on murine macrophages (RAW264.7 cells). In vitro experiments using macrophages demonstrated that BBD-MCMs had more effective immune-stimulating activity than BBD-loaded CMs (BBD-CMs). Mice intranasally immunized with BBD-MCMs showed significantly higher BBD-specific IgA antibody responses in saliva and serum than mice immunized with BBD-CMs (p<0.05). After challenge with B. bronchiseptica via the nasal cavity, groups treated with BBD-MCMs or BBD-CMs showed similar patterns with a high survival rate even though there was no significant difference between those groups. These results suggested that mannose moieties in the MCMs enhanced immune-stimulating activities through mucosal delivery due to a specific interaction between mannose groups in the MCMs and mannose receptors on the macrophages.


Assuntos
Toxinas Bacterianas/administração & dosagem , Quitosana/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Lectinas Tipo C/imunologia , Macrófagos/imunologia , Lectinas de Ligação a Manose/imunologia , Manose/química , Receptores de Superfície Celular/imunologia , Transglutaminases/administração & dosagem , Vacinação/métodos , Fatores de Virulência de Bordetella/administração & dosagem , Administração Intranasal , Animais , Toxinas Bacterianas/química , Células Cultivadas , Quimioterapia Adjuvante/métodos , Estudos de Viabilidade , Macrófagos/efeitos dos fármacos , Receptor de Manose , Camundongos , Microesferas , Transglutaminases/química , Fatores de Virulência de Bordetella/química
18.
Vaccine ; 25(23): 4602-10, 2007 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-17485148

RESUMO

We have studied a vaccine delivery system in vitro and in vivo based on chitosan microspheres (CMs) prepared in the presence of selected immunomodulators, Pluronic block copolymer F127 (F127). The Bordetella bronchiseptica multiple antigens containing dermonecrotoxin (BBD), a virulent factor leading to atrophic rhinitis (AR) in swine was loaded in CMs/F127 or CMs alone. The microspheres, prepared using an ionic gelation process with tripolyphosphate, demonstrated release profiles that showed a greater amount of BBD being released from BBD-loaded CMs/F127 (BBD-CMs/F127). In vitro experiments using mouse alveolar macrophage cells (RAW 264.7) demonstrated that BBD-CMs/F127 have significantly higher immune-stimulating activities than controls. The highest immune-stimulating activities by the BBD-CMs/F127 using RAW 264.7 cells were mirrored in the in vivo studies following nasal administration to mice. The mice immunized with BBD-CMs/F127 showed higher BBD specific IgA antibody responses in nasal wash, saliva and serum than mice immunized with BBD-CMs alone. Protective immunity was measured by survival rate after challenge with B. bronchiseptica via the nasal cavity. The survival rate of the group treated with BBD-CMs/F127 was higher than those of other groups. These results suggested that CMs/F127 represents a novel mucosal delivery system and that F127 could enhance the delivery of BBD-CMs in the vaccination scheme.


Assuntos
Adjuvantes Imunológicos/farmacologia , Antígenos de Bactérias/administração & dosagem , Toxinas Bacterianas/imunologia , Vacinas Bacterianas/administração & dosagem , Bordetella bronchiseptica/imunologia , Quitosana/administração & dosagem , Microesferas , Poloxâmero/farmacologia , Transglutaminases/imunologia , Fatores de Virulência de Bordetella/imunologia , Administração Intranasal , Animais , Anticorpos Antibacterianos/biossíntese , Antígenos de Bactérias/imunologia , Vacinas Bacterianas/imunologia , Linhagem Celular , Feminino , Imunoglobulina A/biossíntese , Imunoglobulina G/biossíntese , Camundongos , Camundongos Endogâmicos ICR , Fator de Necrose Tumoral alfa/biossíntese
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA