共查询到20条相似文献,搜索用时 31 毫秒
1.
Biodegradable nanospheres or microspheres have been widely used as a sustained release system for the delivery of bioagents. In the present study, injectable sustained-release growth hormone-releasing factor (GRF) (1-32) microspheres were prepared by a double emulsion-in liquid evaporation process using biodegradable polylactic-co-glycolic acid (PLGA) as the carrier. The entrapment efficiency was 89.79% and the mean particle size was 4.41 mum. The microspheres were injected into mouse tibialis muscle. After 30 days, mice injected with GRF (1-32) microspheres (group I) gained significantly more weight than any other treatment group, including mice injected with the naked plasmid (group II) (10.26 +/- 0.13 vs. 9.09 +/- 0.56; P < 0.05), a mixture of microspheres and plasmid (group III) (10.26 +/- 0.13 vs. 8.57 +/- 0.02; P < 0.05), or saline (IV) (10.26 +/- 0.13 vs. 6.47 +/- 0.26; P < 0.05). In addition, mice treated with the GRF (1-32) microspheres exhibited the highest expression levels of GRF as detected by PCR, RT-PCR, and ELISA (mean 2.56 +/- 0.40, P < 0.05, overall comparison of treatment with groups II, III, and IV). Additionally, rabbits were injected in the tibialis muscle with the same treatments described above. After 30 days, the group treated with GRF (1-32) microspheres gained the most weight. At day 30 postinjection, weight gain in group I was 63.93% higher than group II (plasmid) (877.10 +/- 24.42 vs. 535.05 +/- 26.38; P < 0.05), 108.59% higher than group III (blank MS) (877.10 +/- 24.42 vs. 420.50 +/- 19.39; P < 0.05), and 93.94% higher than group IV (saline) (877.10 +/- 24.42 vs. 452.25 +/- 27.38; P < 0.05). Furthermore, IGF-1 levels in the serum from GRF microsphere-treated group were elevated relative to all other groups. The present results suggest that encapsulation of GRF with PLGA increases GRF gene expression in muscle after local plasmid delivery, and stimulates significantly more weight gain than delivery of the naked plasmid alone. 相似文献
2.
Dental implantation is an effective standard treatment modality to restore missing teeth and maxillofacial defects. However, in diabetics there is an increased risk for implant failure due to impaired peri-implant osseous healing. Early topical insulin treatment was recently shown to normalize diabetic bone healing by rectifying impairments in osteoblastic activities. In this study, insulin/poly(lactic-co-glycolic acid) (PLGA) microspheres were prepared by a double-emulsion solvent evaporation method. Microspheres were then incorporated in fibrin gel to develop a local drug delivery system for diabetic patients requiring implant treatment. In vitro release of insulin from fibrin gel loaded with these microspheres was assessed, and sustained prolonged insulin release over 21 days ascertained. To assess the bioactivity of released insulin and determine whether slow release might improve impaired diabetic bone formation, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), alkaline phosphatase (ALP) activity, mineralized nodule formation, and ELISA (enzyme-linked immunosorbent assay) assays were performed. The insulin released from the drug delivery system stimulated cell growth in previously inhibited cells, and ameliorated the impaired bone-forming ability of human MG-63 cells under high glucose conditions. Fibrin gel loaded with insulin/PLGA microspheres shows potential for improving peri-implant bone formation in diabetic patients. 相似文献
3.
The stability, in vitro release, and in vitro cell transfection efficiency of plasmid DNA (pDNA) poly (D,L.-lactide-co-glycolide)
(PLGA) microsphere formulations were investigated. PLGA microspheres containing free and polylysine (PLL)-complexed pDNA were
prepared by a water-oil-water solvent extraction/evaporation technique. Encapsulation enhanced the retention of the supereoiled
structure of pDNA as determined by gel electrophoresis. PLL complexation of pDNA prior to encapsulation increased both the
stability of the supercoiled form and the encapsulation efficiency. Free pDNA was completely degraded after exposure to DNase
while encapsulation protected the pDNA from enzymatic degradation. Rapid initial in vitro release of pDNA was obtained from
microspheres containing free pDNA. while the release from microspheres containing PLL-complexed pDNA was sustained for more
than 42 days. Bioactivity of encapsulated pDNA determined by in vitro cell transfection using Chinese hamster ovary cells
(CHO) showed that the bioactivity of encapsulated pDNA was retained in both formulations but to a greater extent with PLL-complexed
pDNA microspheres. These results demonstrated that PLGA microspheres could be used to formulate a controlledrelease delivery
system for pDNA that can protect the pDNA from DNase degradation without loss of functional activity. 相似文献
4.
The aim of this study was the development of a veterinary dosage form constituted by injectable biodegradable microspheres
designed for the subcutaneous release of carboplatin, a chemotherapeutic drug. Poly(D,L-lactide) (PDLLA) microspheres were
prepared by an emulsification/spray-drying method, using the drug-to-polymer weight ratios 1∶9 and 1∶5; blank microspheres
(1% w/v) were prepared as a comparison. Microparticles were characterized in terms of morphology, encapsulation efficiency,
and in vitro drug release behavior. In vivo tests were conducted on rats by subcutaneous injection of microsphere aqueous
suspensions. Levels of carboplatin were evaluated both in the skin and in serum. The microparticles obtained had a spherical
shape; particle size ranged from 5 to 7 μm, dependent on drug loading. Microspheres were able to control the in vitro release
of the drug: approximately 90% to 100% of the carboplatin was released over 30 days. In vivo results showed that the microspheres
were able to release high drug amounts locally, and sustained serum levels of drug were also achieved. Based on these results,
carboplatin-loaded PDLLA microspheres may be useful for local delivery of the antineoplastic drug to the tumor, avoiding tumor
recurrence in small animals, and may decrease the formation of distant metastases.
Published: September 20, 2005 相似文献
5.
Jeon O Song SJ Yang HS Bhang SH Kang SW Sung MA Lee JH Kim BS 《Biochemical and biophysical research communications》2008,369(2):774-780
In this study, heparin-conjugated poly(l-lactide-co-glycolide) (PLGA) nanospheres (HCPNs) suspended in fibrin gel (group 1) were developed for a long-term delivery of BMP-2, and then used to address the hypothesis that a long-term delivery of BMP-2 would enhance ectopic bone formation compared to a short-term delivery at an equivalent dose. Fibrin gel containing normal PLGA nanospheres (group 2) was used for short-term delivery of BMP-2. The in vitro release of BMP-2 from group 1 was sustained for 4 weeks with no initial burst release. In contrast, 83% of BMP-2 loaded in group 2 was released only for the first 3 days. BMP-2 released from group 1 stimulated an increase in alkaline phosphatase (ALP) activity of osteoblasts for 9 days in vitro. In contrast, BMP-2 released from group 2 induced a transient increase in ALP activity for the first 5 days and a decrease thereafter. Importantly, group 1 induced bone formation to a much greater extent than did group 2, with 2.0-fold greater bone formation area and 3.5-fold greater calcium content, upon implantation into rat hind limb muscle. These results show that long-term delivery of BMP-2 enhances in vivo osteogenic efficacy of the protein compared to short-term delivery at an equivalent dose. 相似文献
6.
7.
This research compared the binding and release of recombinant human bone morphogenetic protein 2 (rhBMP-2) with a series of
hydrophobic and hydrophilic poly-lactide-co-glycolide (PLGA) copolymers. Porous microspheres were produced via a double emulsion
process. Binding and incorporation of protein were achieved by soaking microspheres in buffered protein solutions, filtering,
and comparing protein concentration remaining to nonmicrosphere-containing samples. Protein release was determined by soaking
bound microspheres in a physiological buffer and measuring protein concentration (by reversed-phase high-performance liquid
chromatography) in solution over time. Normalized for specific surface area and paired by polymer molecular weight. microspheres
made from hydrophilic 50∶50 or 75∶25 PLGA bound significantly more protein than microspheres made from the corresponding hydrophobic
PLGA. Increased binding capacity correlated with higher polymer acid values. With certain polymers, rhBMP-2 adsorption was
decreased or inhibited at high protein concentration, but protein loading could be enhanced by increasing the protein solution:PLGA
(volume:mass) ratio or by repetitive soaking. Microspheres of various PLGAs released unbound protein in 3 days, whereas the
subsequent bound protein release corresponded to mass loss. RhBMP-2 binding to PLGA was controlled by the acid value, protein
concentration, and adsorption technique. The protein released in 2 phases: the first occurred over 3 days regardless of PLGA
used and emanated from unbound, incorporated protein, while the second was controlled by mass loss and therefore was dependent
on the polymer molecular weight. Overall, control of rhBMP-2 delivery is achievable by selection of PLGA microsphere carriers.
Published: October, 7, 2001. 相似文献
8.
Meng XT Li C Dong ZY Liu JM Li W Liu Y Xue H Chen D 《Cell biology international》2008,32(12):1546-1558
We have previously demonstrated that amniotic epithelial cells (AECs) can enhance survival and neural differentiation of neural stem cells (NSCs) when co-cultured in basal media. In addition, the presence of basic fibroblast growth factor (bFGF) enhances this AEC function. The aim of the present study was to extend those findings and investigate whether AECs modified with the bFGF gene will also enhance NSCs survival and neural differentiation in vivo and promote repair of the injured spinal cord. Female Wistar rats were used for a contusive spinal cord injury (SCI) model. Contusive SCIs were induced using a weight-drop device at levels T9-T11. Seven days following contusion, rats received grafts of NSCs only, NSCs with AECs/pLEGFP-hbFGF, or NSCs with AECs/pLEGFP-C1 into the injured region. Significant locomotor improvement was observed in the NSCs/AECs co-graft group beginning at 3 weeks compared with the NSCs or NaCl only groups. These results were confirmed and extended in an electrophysiological analysis. An immunohistological analysis revealed that AECs/pLEGFP-hbFGF promoted the survival (vs NaCl group: 194+/-9.17 vs 103.6+/-13.05) and neural differentiation (vs NaCl group: 14.24+/-1.11 vs 7+/-0.63) of co-transplanted NSCs. We also confirmed that AECs could promote the survival of host neurons. These results suggest that AECs/pLEGFP-hbFGF improve the NSCs survival and differentiation microenvironment and may be useful as a source of sustained trophic supported to improve NSCs differentiation into neurons in vivo. These findings suggest that a cograft of AECs/pLEGFP-hbFGF and NSCs may have benefits for SCI. 相似文献
9.
重组人粒细胞集落刺激因子缓释微球的研究 总被引:1,自引:0,他引:1
目的:研究固体/油/水法制备重组人粒细胞集落刺激因子缓释微球,为开发其缓释剂型进行初步研究。方法:以聚乳酸.聚羟乙酸共聚物(PLGA)为载体材料:用固体/油/水法和水/油/水法制备载rhG-CSF缓释微球;考察粒径大小、外观、包封率等理化性质;用MieroBCA法考察微球的体外释药特性及影响因素;用SEC-HPLC和MTT比色法初步评价了微球制备工艺过程对rhG-CSF稳定性的影响。结果:两种方法制得的微球形态圆整、分散性良好,包封率均超过80%。固/油/水法制得的微球体外释放在2周内可超过90%,而水/油/水法制得的微球在相同的时间内仅释放30%。对于固/油/水法制备过程,SEC-HPLC法测定蛋白无明显聚集体出现,MTT法测定蛋白活性无明显损失。结论:实验证明了固/油/水法制备的PLGA微球可以实现2周以上的体外缓释。 相似文献
10.
XiaoQing Dong Jun Xu WeiCai Wang Hao Luo XiaoFei Liang Lei Zhang HanJie Wang PengHua Wang Jin Chang 《中国科学C辑(英文版)》2008,51(11):1039-1044
In this study the w/o/w extraction-evaporation technique was adopted to prepare poly(lactic-co-glycolic acid) (PLGA) microspheres loading recombinant human epidermal growth factor (rhEGF). The microspheres were characterized
for morphology by transmission electron microscopy (TEM) and particle size distribution. The release performances, the proliferation
effects and therapeutic effects of rhEGF-loaded PLGA microspheres were all studied. The results showed that these spherical
microspheres had a narrow size distribution and a high drug encapsulation efficiency (85.6%). RhEGF-loaded microspheres enhanced
the growth rate of fibroblasts and wound healing more efficiently than pure rhEGF. The number of the proliferating cell nuclear
antigen (PCNA) in the epidermis layer with the microsphere treatment was significantly larger than those of the control groups.
Overall locally sustained delivery of rhEGF from biodegradable PLGA microspheres may serve as a novel therapeutic strategy
for diabetic ulcer repair. 相似文献
11.
Sardarpasha Sheikpranbabu Kalimuthu Kalishwaralal Deepak Venkataraman Soo Hyun Eom Jongsun Park Sangiliyandi Gurunathan 《Journal of nanobiotechnology》2009,7(1):1-12
Antisense oligonucleotides (AOs) have been shown to induce dystrophin expression in muscles cells of patients with Duchenne
Muscular Dystrophy (DMD) and in the mdx mouse, the murine model of DMD. However, ineffective delivery of AOs limits their therapeutic potential. Copolymers of cationic
poly(ethylene imine) (PEI) and non-ionic poly(ethylene glycol) (PEG) form stable nanoparticles when complexed with AOs, but
the positive surface charge on the resultant PEG-PEI-AO nanoparticles limits their biodistribution. We adapted a modified
double emulsion procedure for encapsulating PEG-PEI-AO polyplexes into degradable polylactide-co-glycolic acid (PLGA) nanospheres.
Formulation parameters were varied including PLGA molecular weight, ester end-capping, and sonication energy/volume. Our results
showed successful encapsulation of PEG-PEI-AO within PLGA nanospheres with average diameters ranging from 215 to 240 nm. Encapsulation
efficiency ranged from 60 to 100%, and zeta potential measurements confirmed shielding of the PEG-PEI-AO cationic charge.
Kinetic measurements of 17 kDa PLGA showed a rapid burst release of about 20% of the PEG-PEI-AO, followed by sustained release
of up to 65% over three weeks. To evaluate functionality, PEG-PEI-AO polyplexes were loaded into PLGA nanospheres using an
AO that is known to induce dystrophin expression in dystrophic mdx mice. Intramuscular injections of this compound into mdx mice resulted in over 300 dystrophin-positive muscle fibers distributed throughout the muscle cross-sections, approximately
3.4 times greater than for injections of AO alone. We conclude that PLGA nanospheres are effective compounds for the sustained
release of PEG-PEI-AO polyplexes in skeletal muscle and concomitant expression of dystrophin, and may have translational potential
in treating DMD. 相似文献
12.
Pooja Jain Abhinav Garg Uzma Farooq Amulya K. Panda Mohd. Aamir Mirza Ahmed Noureldeen Hadeer Darwish Zeenat Iqbal 《Saudi Journal of Biological Sciences》2021,28(5):2677-2685
PLGA (Lactic- co-glycolic acid) coated chitosan microspheres loaded with hydroxyapatite and doxycycline hyclate complex were developed in the present study for periodontal delivery. A modified single emulsion method was adopted for the development of microspheres. Formulation was optimized on the basis of particle size, drug loading and encapsulation efficiency with the central composite design using 23 factorial design. Microspheres were optimized and electron microscopy revealed their spherical shape and porous nature. In-vitro study showed initial burst and then sustained release behavior of the formulation for 14 days. Further, in-vitro antibacterial study performed on E. coli (ATCC-25922) and S. aureus (ATCC-29213) revealed concentration dependent activity. Also, in-vitro cyto-toxicity assessment ensures biocompatibility of the formulation with the fibroblast’s cells. Overall, the quality by design assisted PLGA microspheres, demonstrated the desired attributes and were found suitable for periodontal drug delivery. 相似文献
13.
Biological activity of rhBMP-2 released from PLGA microspheres 总被引:20,自引:0,他引:20
Oldham JB Lu L Zhu X Porter BD Hefferan TE Larson DR Currier BL Mikos AG Yaszemski MJ 《Journal of biomechanical engineering》2000,122(3):289-292
Human recombinant bone morphogenetic protein-2 (rhBMP-2) has been proven effective in stimulating the regeneration of bone in both skeletal and extraskeletal locations. Through encapsulation within, and release from, biodegradable poly(DL-lactic-co-glycolic acid) (PLGA) microspheres, a proven vehicle for sustained delivery of various proteins, the local concentrations of rhBMP-2 could be maintained at optimal levels to stimulate bone regeneration and remodeling at the site of healing in diverse clinical settings. Thus the purpose of this work was to investigate the encapsulation of rhBMP-2 in PLGA microspheres and its biologic activity upon release. Using in vitro tests in simulated body fluids, the effect of rhBMP-2 released from PLGA microspheres upon osteoblast cell cultures was found to be statistically similar to the effect produced by positive controls consisting of nonencapsulated aqueous rhBMP-2 in simulated body fluids. This clarifies an important step in skeletal tissue engineering strategies aimed at the use of encapsulated rhBMP-2 to stimulate bone regeneration and remodeling. 相似文献
14.
Cellular response to empty and palladium‐conjugated amino‐polystyrene nanospheres uptake: A proteomic study
下载免费PDF全文
![点击此处可从《Proteomics》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Laura Pietrovito Victoria Cano‐Cortés Tania Gamberi Francesca Magherini Laura Bianchi Luca Bini Mauro Fasano Alessandra Modesti 《Proteomics》2015,15(1):34-43
Amino polystyrene nanospheres are shown to be efficient and controllable delivery devices, capable of transporting several bioactive cargoes. Recently, the design of a new device for prodrug activation, using these nanospheres with palladium encapsulated onto them, has been developed successfully. To study the influence of the cellular uptake of these nanodevices, we investigated the cellular response of human embryonic kidney cells (HEK‐293T) and murine fibroblasts (L929) treated with empty or palladium‐conjugated amino polystyrene nanospheres. To identify differentially expressed proteins, we performed an exhaustive proteomic analysis. In accordance with genomic data previously obtained, the uptake of the empty nanospheres did not induce significant variation in protein expression levels. Following the treatment with palladium‐conjugated nanospheres, some changes in protein profiles in both cell lines were observed; these alterations affect proteins involved in cell metabolism and intracellular transport. No key regulator of the cell cycle result was differentially expressed after the treatment, confirming that these innovative drug delivery systems are harmless and well tolerated by the cells. 相似文献
15.
Formation and oral administration of alginate microspheres loaded with pDNA coding for lymphocystis disease virus (LCDV) to Japanese flounder 总被引:1,自引:0,他引:1
Oral delivery of plasmid DNA (pDNA) is a desirable approach for fish immunization in intensive culture. However, its effectiveness is limited because of possible degradation of pDNA in the fish's digestive system. In this report, alginate microspheres loaded with pDNA coding for fish lymphocystis disease virus (LCDV) and green fluorescent protein were prepared with a modified oil containing water (W/O) emulsification method. Yield, loading percent and encapsulation efficiency of alginate microspheres were 90.5%, 1.8% and 92.7%, respectively. The alginate microspheres had diameters of less than 10 microm, and their shape was spherical. As compared to sodium alginate, a remarkable increase of DNA-phosphodiester and DNA-phosphomonoester bonds was observed for alginate microspheres loaded with pDNA by Fourier transform infrared (FTIR) spectroscopic analysis. Agarose gel electrophoresis showed a little supercoiled pDNA was transformed to open circular and linear pDNA during encapsulation. The cumulative release of pDNA in alginate microspheres was or=0.3) for anti-LCDV antibody from week 3 to week 16 for fish orally vaccinated with alginate microspheres loaded with pDNA, in comparison with fish orally vaccinated with naked pDNA. Our results display that alginate microspheres obtained by W/O emulsification are promising carriers for oral delivery of pDNA. This encapsulation technique has the potential for DNA vaccine delivery applications due to its ease of operation, low cost and significant immune effect. 相似文献
16.
Expression and histochemical localization of ciliary neurotrophic factor in cultured adult rat dorsal root ganglion neurons 总被引:4,自引:3,他引:1
Ciliary neurotrophic factor (CNTF) is abundantly expressed in Schwann cells in adult mammalian peripheral nerves, but not
in neurons. After peripheral nerve injury, CNTF released from disrupted Schwann cells is likely to promote neuronal survival
and axonal regeneration. In the present study, we examined the expression and histochemical localization of CNTF in adult
rat DRG in vivo and in vitro. In contrast to the restricted expression in Schwann cells in vivo, we observed abundant CNTF
mRNA and protein expression in DRG neurons after 3 h, 2, 7, and 15 days in dissociated cell culture. At later stages (7 and
15 days) of culture, CNTF immunoreactivity was detected in both neuronal cell bodies and regenerating neurites. These results
suggest that CNTF is synthesized and transported to neurites in cultured DRG neurons. Since we failed to observe CNTF immunoreactivity
in DRG neurons in explant culture, disruption of cell–cell interactions, rather than the culture itself, may be an inducible
factor for localization of CNTF in the neurons. 相似文献
17.
Kassab R Parrot-Lopez H Fessi H Menaucourt J Bonaly R Coulon J 《Bioorganic & medicinal chemistry》2002,10(6):1767-1775
In an effort to develop a new way of drug delivery, especially for polyenic antifungal molecules, we have incorporated amphotericin B (AmB) into biodegradable galactosylated poly (L-lactic acid) (L-PLA) and poly (L-lactic-co-glycolic acid) (PLGA) microspheres. These drug carriers were prepared by solvent evaporation using an oil/water (o/w) emulsion. The ratio of galactosyl spacers with different chain lengths was 1.74-2.78%. The maximal quantity of AmB encapsulated reported to 100 mg of the galactosylated microspheres was 7.14 mg for L-PLA (encapsulation rate 45% of mole) and 6.42 mg for PLGA derivatives (encapsulation rate 81% of mole). In our yeast model, drug release depended on three factors: (i) presence of galactosylated antennae, (ii) length of galactosyl antenna and (iii) nature of the polymer. More of the AmB trapped in PLGA microspheres was released than from PLA microspheres. These novel functionalised microspheres could be required for the delivering of therapeutic agents according to their recognition to specific cells. 相似文献
18.
Yong-liang Zhang Xiao-hui Ren Song-cai Liu Jian-wei Dai Lin-lin Hao Qing-yan Jiang 《Animal biotechnology》2013,24(3):163-175
Biodegradable nanospheres or microspheres have been widely used as a sustained release system for the delivery of bioagents. In the present study, injectable sustained-release growth hormone-releasing factor (GRF) (1–32) microspheres were prepared by a double emulsion-in liquid evaporation process using biodegradable polylactic-co-glycolic acid (PLGA) as the carrier. The entrapment efficiency was 89.79% and the mean particle size was 4.41 μm. The microspheres were injected into mouse tibialis muscle. After 30 days, mice injected with GRF (1–32) microspheres (group I) gained significantly more weight than any other treatment group, including mice injected with the naked plasmid (group II) (10.26 ± 0.13 vs. 9.09 ± 0.56; P < 0.05), a mixture of microspheres and plasmid (group III) (10.26 ± 0.13 vs. 8.57 ± 0.02; P < 0.05), or saline (IV) (10.26 ± 0.13 vs. 6.47 ± 0.26; P < 0.05). In addition, mice treated with the GRF (1–32) microspheres exhibited the highest expression levels of GRF as detected by PCR, RT-PCR, and ELISA (mean 2.56 ± 0.40, P < 0.05, overall comparison of treatment with groups II, III, and IV). Additionally, rabbits were injected in the tibialis muscle with the same treatments described above. After 30 days, the group treated with GRF (1–32) microspheres gained the most weight. At day 30 postinjection, weight gain in group I was 63.93% higher than group II (plasmid) (877.10 ± 24.42 vs. 535.05 ± 26.38; P < 0.05), 108.59% higher than group III (blank MS) (877.10 ± 24.42 vs. 420.50 ± 19.39; P < 0.05), and 93.94% higher than group IV (saline) (877.10 ± 24.42 vs. 452.25 ± 27.38; P < 0.05). Furthermore, IGF-1 levels in the serum from GRF microsphere-treated group were elevated relative to all other groups. The present results suggest that encapsulation of GRF with PLGA increases GRF gene expression in muscle after local plasmid delivery, and stimulates significantly more weight gain than delivery of the naked plasmid alone. 相似文献
19.
Wanda Jankowiak Katharina Kruszewski Kai Flachsbarth Christos Skevas Gisbert Richard Klaus Rüther Thomas Braulke Udo Bartsch 《PloS one》2015,10(5)
A sustained intraocular administration of neurotrophic factors is among the strategies aimed at establishing treatments for currently untreatable degenerative retinal disorders. In the present study we have analyzed the neuroprotective effects of a continuous neural stem (NS) cell-based intraocular delivery of ciliary neurotrophic factor (CNTF) on photoreceptor cells in the nclf mouse, an animal model of the neurodegenerative lysosomal storage disorder variant late infantile neuronal ceroid lipofuscinosis (vLINCL). To this aim, we genetically modified adherently cultivated NS cells with a polycistronic lentiviral vector encoding a secretable variant of CNTF together with a Venus reporter gene (CNTF-NS cells). NS cells for control experiments (control-NS cells) were modified with a vector encoding the reporter gene tdTomato. Clonal CNTF-NS and control-NS cell lines were established using fluorescent activated cell sorting and intravitreally grafted into 14 days old nclf mice at the onset of retinal degeneration. The grafted cells preferentially differentiated into astrocytes that were attached to the posterior side of the lenses and the vitreal side of the retinas and stably expressed the transgenes for at least six weeks, the latest post-transplantation time point analyzed. Integration of donor cells into host retinas, ongoing proliferation of grafted cells or adverse effects of the donor cells on the morphology of the host eyes were not observed. Quantitative analyses of host retinas two, four and six weeks after cell transplantation revealed the presence of significantly more photoreceptor cells in eyes with grafted CNTF-NS cells than in eyes with grafted control-NS cells. This is the first demonstration that a continuous intraocular administration of a neurotrophic factor attenuates retinal degeneration in an animal model of neuronal ceroid lipofuscinosis. 相似文献
20.
The in vitro and in vivo characterization of cell-loaded immobilization devices is an important challenge in cell encapsulation technology for the long-term efficacy of this approach. In the present paper, alginate-poly-l-lysine-alginate (APA) microcapsules containing erythropoietin (Epo)-secreting C2C12 myoblasts have been elaborated, characterized, and tested both in vitro and in vivo. High mechanical and chemical resistance of the elaborated microcapsules was observed. Moreover, the in vitro cultured encapsulated cells released 81.9 +/- 8.2 mIU/mL/24 h (by 100 cell-loaded microcapsules) by day 7, reaching the highest peak at day 21 (161.7 +/- 0.9 mIU/mL/24 h). High and constant hematocrit levels were maintained over 120 days after a single subcutaneous administration of microcapsules and lacking immunosuppressive protocols. No major host reaction was observed. On the basis of the results obtained in our study, cell encapsulation technology might be considered a suitable therapeutic strategy for the long-term delivery of biologically active products, such as Epo. 相似文献