In vivo transplantation of stem cells with a genipin linked scaffold for tracheal construction.

To establish the procedures of genipin-linked scaffold for in situ tracheal reconstruction in a rabbit model, and to demonstrate whether stem cells can be further differentiated in the bioreactor in vivo. It will further provide an experimental and theoretical foundation for clinical application. Previously, in vitro evaluation proved the detergent­enzymatic method effectively removed stromal epithelial cells, and the number of nuclei was reduced significantly (p < 0.05). The content of type II collagen was not statistically reduced (p > 0.05). Plasmids with green fluorescence protein were transfected into 293T cells, and these cells subsequently synthesized lentivirus with green fluorescence protein that could infect other cells. After in vivo experiments, macroscopic specimen observation and hematoxylin and eosin staining comparison showed that the genipin cross-linked decellularized scaffold had low immunological rejection. Blood routine proved the progenitor cells (such as mononuclear cells) can be mobilized from the bone marrow by the growth factors, to allow their circulation into the peripheral blood. The immunohistochemistry of Type II collagen after surgery showed the expression level of bone marrow mesenchymal stem cells transplantated group was statistically higher than the autologous transplantated group (p < 0.05). The fluorescences of Bone marrow mononuclear cells (BMNCs) were traced after the specimens harvested. It successfully demonstrated that the procedures combining stem cells with the genipin cross-linked decellularized scaffold could apply to in situ airway construction. Compared to bone marrow mesenchymal stem cells, BMNCs can also be used to achieve chondrocyte differentiation; this procedure will avoid in vitro cell culture, shortening the time and economic costs.

Fluorescence properties of curcumin-loaded nanoparticles for cell tracking.

BACKGROUND: Posttransplant cell tracking, via stem cell labeling, is a crucial strategy for monitoring and maximizing benefits of cell-based therapies. The structures and functionalities of polysaccharides, proteins, and lipids allow their utilization in nanotechnology systems. MATERIALS AND METHODS: In the present study, we analyzed the potential benefit of curcumin-loaded nanoparticles (NPC) using Vero cells (in vitro) and NPC-labeled adipose-derived mesenchymal stem cells (NPC-ADMSCs) (in vivo) in myocardial infarction and sciatic nerve crush preclinical models. Thereafter, transplantation, histological examination, real time imaging, and assessment of tissue regeneration were done. RESULTS: Transplanted NPC-ADMSCs were clearly identified and revealed potential benefit when used in cell tracking. CONCLUSION: This approach may have broad applications in modeling labeled transplanted cells and in developing improved stem cell therapeutic strategies.

A series of Cre-ER(T2) drivers for manipulation of the skeletal muscle lineage.

We report the generation of five mouse strains with the tamoxifen-inducible Cre (Cre-ER(T) (2) ; CE) gene cassette knocked into the endogenous loci of Pax3, Myod1, Myog, Myf6, and Myl1, collectively as a resource for the skeletal muscle research community. We characterized these CE strains using the Cre reporter mice, R26R(L) (acZ) , during embryogenesis and show that they direct tightly controlled tamoxifen-inducible reporter expression within the expected cell lineage determined by each myogenic gene. We also examined a few selected adult skeletal muscle groups for tamoxifen-inducible reporter expression. None of these new CE alleles direct reporter expression in the cardiac muscle. All these alleles follow the same knock-in strategy by replacing the first exon of each gene with the CE cassette, rendering them null alleles of the endogenous gene. Advantages and disadvantages of this design are discussed. Although we describe potential immediate use of these strains, their utility likely extends beyond foreseeable questions in skeletal muscle biology.

Lineage analysis of transplanted individual cells in embryos of Drosophila melanogaster : I. The method.

A method is presented which allows the study of the progeny of single cells during Drosophila embryogenesis. Cells from various larval anlagen of donor embryos labelled with a lineage tracer are individually transplanted from defined positions into similar, or different, positions in unlabelled hosts. The clones produced by these cells can be seen in whole mounts or in sections of fixed material, when using a histochemical marker (i.e. HRP), and/or in living embryos, when using fluorescent lineage tracers. The characteristics of the clones disclose lineage parameters, such as division patterns, morphogenetic movements and differentiation. The method is especially useful for testing the respective roles of positional information and cell lineage on the commitment of progenitor cells by transplanting these cells into heterotopic positions or into hosts of different genotypes.