Evaluation of MicroRNA Delivery In Vivo

Author(s):  
Rikki A. M. Brown ◽  
Kirsty L. Richardson ◽  
Felicity C. Kalinowski ◽  
Michael R. Epis ◽  
Jessica L. Horsham ◽  
...  
Keyword(s):  
2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Anna Schade ◽  
Paula Müller ◽  
Evgenya Delyagina ◽  
Natalia Voronina ◽  
Anna Skorska ◽  
...  

Genetic modifications of bone marrow derived human mesenchymal stem cells (hMSCs) using microRNAs (miRs) may be used to improve their therapeutic potential and enable innovative strategies in tissue regeneration. However, most of the studies use cultured hMSCs, although these can lose their stem cell characteristics during expansion. Therefore, we aimed to develop a nonviral miR carrier based on polyethylenimine (PEI) bound to magnetic nanoparticles (MNPs) for efficient miR delivery in freshly isolated hMSCs. MNP based transfection is preferable for genetic modificationsin vivodue to improved selectivity, safety of delivery, and reduced side effects. Thus, in this study different miR/PEI and miR/PEI/MNP complex formulations were testedin vitrofor uptake efficiency and cytotoxicity with respect to the influence of an external magnetic field. Afterwards, optimized magnetic complexes were selected and compared to commercially available magnetic vectors (Magnetofectamine, CombiMag). We found that all tested transfection reagents had high miR uptake rates (yielded over 60%) and no significant cytotoxic effects. Our work may become crucial for virus-free introduction of therapeutic miRs as well as other nucleic acidsin vivo. Moreover, in the field of targeted stem cell therapy nucleic acid delivery prior to transplantation may allowfor initial cell modulationin vitro.


2019 ◽  
Vol 15 (7) ◽  
pp. 1492-1505 ◽  
Author(s):  
Keyu Wei ◽  
Feila Liu ◽  
Jingyuan Yang ◽  
Da Huo ◽  
Ge Guan ◽  
...  

Rapid endothelialization of tissue-engineered blood vessels (TEBVs) is an essential strategy to inhibit thrombosis, chronic inflammation and intimal hyperplasia after transplantation into the body. Monocytes will be recruited to the transplantation site and converted to macrophages after TEBV implantation. Macrophages play an important role in angiogenesis; however, whether engineered macrophages can be utilized to promote rapid endothelialization of TEBVs remains unclear. Thus, a cell bioreactor that can engineer macrophages via graphene quantum dot (GQD)-mediated microRNA (miR) delivery was built in the TEBV. Briefly, GQD-miR-150 linked by disulfide bonds was adopted to functionalize both the inner and outer TEBVs. The GQD-miR-150 conjugation as an intracellular gene delivery system was taken up by macrophages. Under the protection of GQDs, miR-150 was transfected into the cytosol, allowing continuous secretion of vascular endothelial growth factor (VEGF) via upregulation of HIF-1α protein expression, and promoted the migration of endothelial cells (ECs) in vitro. An in vivo study showed a rapid endothelialization of the inner TEBVs after transplantation for 7 days, especially a holonomic endothelial layer after 30 days. For the outer TEBVs, neovascularization (vasa vasorum) accompanied by nerve growth was observed around the adventitia on day 90. In conclusion, the designed cell bioreactor consisting of GQD-miR-engineered macrophages can effectively promote endothelialization and neuralization in vivo for TEBVs.


2018 ◽  
Vol 16 (1) ◽  
pp. 1257-1267 ◽  
Author(s):  
Chen CY ◽  
Li GY ◽  
Zhang L ◽  
Huang XH ◽  
Cheng D ◽  
...  

AbstractA microRNA (miRNA) nanomedicine PEG-PEI/miR-221/222 was synthesized based on PEGylated polyethylenimine PEG-PEI and used to transfect prostate cancer cells (PC-3) in vitro. Gel retardation assay confirmed the formation of nanomedicine, of which the zeta potential and particle size were determined by dynamic light scattering. Its cytotoxicity was analyzed by CCK-8 assay-while its transfection efficiency was analyzed by flow cytometry. Cell uptake and intracellular distribution of nanoparticles were evaluated using laser confocal microscopy. RT-PCR and western-blot assays were conducted to verify the regulation of SIRT1 target gene. We found that the properties of the nanocomplexes of miRNA and PEG-PEI depended on N/P ratios. At higher N/P ratio, accompanied by higher zeta potential and higher cytotoxicity, PEG-PEI is needed to completely condense the miRNA into small particles with uniform size distribution. Under an N/P ratio of 20, high transfection efficiency and low carrier cytotoxicity were obtained simultaneously in PC-3 cells in vitro. Consequently, the SIRT1 expression was up-regulated due to the nanoparticle-delivered miR-221/222, which resulted in effective inhibition of PC-3 cells. Our study revealed the PEG-PEI/miR-221/222 nanomedicine as a prospective alternative for treatment of advanced prostate cancer and also lays a foundation for future in vivo investigation.


Author(s):  
S. Phyllis Steamer ◽  
Rosemarie L. Devine

The importance of radiation damage to the skin and its vasculature was recognized by the early radiologists. In more recent studies, vascular effects were shown to involve the endothelium as well as the surrounding connective tissue. Microvascular changes in the mouse pinna were studied in vivo and recorded photographically over a period of 12-18 months. Radiation treatment at 110 days of age was total body exposure to either 240 rad fission neutrons or 855 rad 60Co gamma rays. After in vivo observations in control and irradiated mice, animals were sacrificed for examination of changes in vascular fine structure. Vessels were selected from regions of specific interest that had been identified on photomicrographs. Prominent ultrastructural changes can be attributed to aging as well as to radiation treatment. Of principal concern were determinations of ultrastructural changes associated with venous dilatations, segmental arterial stenosis and tortuosities of both veins and arteries, effects that had been identified on the basis of light microscopic observations. Tortuosities and irregularly dilated vein segments were related to both aging and radiation changes but arterial stenosis was observed only in irradiated animals.


Author(s):  
E. J. Kollar

The differentiation and maintenance of many specialized epithelial structures are dependent on the underlying connective tissue stroma and on an intact basal lamina. These requirements are especially stringent in the development and maintenance of the skin and oral mucosa. The keratinization patterns of thin or thick cornified layers as well as the appearance of specialized functional derivatives such as hair and teeth can be correlated with the specific source of stroma which supports these differentiated expressions.


Author(s):  
M.J. Murphy ◽  
R.R. Price ◽  
J.C. Sloman

The in vitro human tumor cloning assay originally described by Salmon and Hamburger has been applied recently to the investigation of differential anti-tumor drug sensitivities over a broad range of human neoplasms. A major problem in the acceptance of this technique has been the question of the relationship between the cultured cells and the original patient tumor, i.e., whether the colonies that develop derive from the neoplasm or from some other cell type within the initial cell population. A study of the ultrastructural morphology of the cultured cells vs. patient tumor has therefore been undertaken to resolve this question. Direct correlation was assured by division of a common tumor mass at surgical resection, one biopsy being fixed for TEM studies, the second being rapidly transported to the laboratory for culture.


Author(s):  
H. Engelhardt ◽  
R. Guckenberger ◽  
W. Baumeister

Bacterial photosynthetic membranes contain, apart from lipids and electron transport components, reaction centre (RC) and light harvesting (LH) polypeptides as the main components. The RC-LH complexes in Rhodopseudomonas viridis membranes are known since quite seme time to form a hexagonal lattice structure in vivo; hence this membrane attracted the particular attention of electron microscopists. Contrary to previous claims in the literature we found, however, that 2-D periodically organized photosynthetic membranes are not a unique feature of Rhodopseudomonas viridis. At least five bacterial species, all bacteriophyll b - containing, possess membranes with the RC-LH complexes regularly arrayed. All these membranes appear to have a similar lattice structure and fine-morphology. The lattice spacings of the Ectothiorhodospira haloohloris, Ectothiorhodospira abdelmalekii and Rhodopseudomonas viridis membranes are close to 13 nm, those of Thiocapsa pfennigii and Rhodopseudomonas sulfoviridis are slightly smaller (∼12.5 nm).


Author(s):  
Frederick A. Murphy ◽  
Alyne K. Harrison ◽  
Sylvia G. Whitfield

The bullet-shaped viruses are currently classified together on the basis of similarities in virion morphology and physical properties. Biologically and ecologically the member viruses are extremely diverse. In searching for further bases for making comparisons of these agents, the nature of host cell infection, both in vivo and in cultured cells, has been explored by thin-section electron microscopy.


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