[Show abstract][Hide abstract] ABSTRACT: Mutations in the gene of connexin 26 (Cx26) are the most common cause of human non‑syndromic hereditary deafness. The pathogenesis of deafness caused by Cx26 remains uncertain. To explore the basic mechanism underlying Cx26 null mutations, ultrastructural changes and a number of marker proteins in the cochlear sensory epithelium of Cx26 conditional knockout mice were observed in the current study. Cochlear specimens were obtained from Cx26 conditional knockout mice (cCx26ko), while wild‑type mice served as controls. Antibodies against the pillar cell marker P75, the supporting cell marker prox1 and hair cell markers myosin 6 and phalloidin were labeled in different cells of the cochlear sensory epithelium of cochlear cryosections. The ultrastructural morphology of cochlear sensory epithelium was observed using transmission electron microscopy. Following the observation of cochlear sensory epithelium cell markers for hair cells and supporting cells, no significant changes were observed at the early stage, while the tunnel of the organ of Corti and Nuel's space was not developed prior to hearing onset in cCx26 knockout mice. Cell death was observed from postnatal day 10 (P10). The only region of surviving cells observed in the cochlea was the Hensen cell region, where microglia‑like cells appeared following P180. Overall, the present study showed an abnormal ultrastructural morphology in the cochlear sensory epithelium in cCx26ko mice. Microglia‑like cells may be involved in the process of cell degeneration in cCx26ko mice.
Preview · Article · Aug 2013 · Molecular Medicine Reports
[Show abstract][Hide abstract] ABSTRACT: Induced pluripotent stem cells (iPSCs) are generated by reprogramming mouse or human somatic cells to a pluripotent state by introducing key transcription factors and have great therapeutic potential. It has been illustrated that the transcriptional and post-transcriptional profiles of nuclear-transferred embryonic stem cells (ntESCs) is identical to those of embryonic stem cells derived from fertilized blastocysts (fESCs). Although iPSCs seem to be indistinguishable from fESCs, the degree of transcriptomic and proteomic similarity among iPSCs, ntESCs, and fESCs has not yet been elucidated completely. To investigate whether iPSCs and fESCs have similar therapeutic potential, we compared mRNA and protein pro?les of mouse iPSC, ntESCs, and matching fESCs lines using microarray technology, iTRAQ method, and bioinformatic analyses. Real-time PCR, two-dimensional LC, and MS/MS analyses were further conducted to study the expression of speci?c transcripts and identify and quantitate 929 proteins. Our results demonstrate that, like ntESCs, the iPSC and matching fESCs lines have very similar transcriptional and protein expression profiles. This is consistent with their similar developmental potential.
No preview · Article · Jan 2012 · Frontiers in Bioscience
[Show abstract][Hide abstract] ABSTRACT: To develop a novel non-viral vector with high transfection efficiency and low cytotoxicity.
Poly (ethylene glycol)-distearoylphosphatidylethanolamine (PEG-DSPE) was incorporated into polymer-lipid hybrid nanoparticles (PLN) to construct a PEG-DSPE modified long circulating PLN (L-PLN). The L-PLN was prepared by the emulsifying-solvent evaporation method, L-PLN and L-PLN/DNA complexes were characterized. Both HEK293 and MDA-MB-231 cells transfected by L-PLN/DNA complexes were observed under a fluorescence microscope. The transfection efficiency of the complexes to HEK293 cells was further evaluated by flow cytometry.
The GFP fluorescence intensity in HEK293 cells transfected by the L-PLN/DNA complexes (N/P=10) was about 37.2%, which was higher than those transfected by PLN alone or commercial Lipofectamine 2000. The L-PLN exhibited minimal toxicity at a low N/P ratio compared with other vectors.
L-PLN as a novel gene delivery system, has higher transfection efficiency and acceptable cytotoxicity compared to the corresponding PLN, which is beneficial for the development of non-viral gene transfer vectors and may offer an alternative strategy for the future gene therapy.
Preview · Article · Mar 2010 · Acta Pharmacologica Sinica