Clinical Assessment of Intravenous Endothelial Progenitor Cell Transplantation in Dogs.

Endothelial progenitor cells (EPCs) have been applied for cell therapy because of their roles in angiogenesis and neovascularization in ischemic tissue. However, adverse responses caused by EPC therapy have not been fully investigated. In this study, a human peripheral blood sample was collected from a healthy donor and peripheral blood mononuclear cells were separated using Ficoll-Hypaque. There were four experimental groups: 10 ml saline infusion group (injection rate; 3 ml/min), 10 ml saline bolus group (injection rate; 60 ml/min), 10 ml EPCs infusion group (2 x 105 cells/ml, injection rate; 3 ml/min), 10 ml EPCs bolus group (2 × 105 cells/ml, injection rate; 60 ml/min). Clinical assessment included physical examination and laboratory examination for intravenous human EPC transplantation in dogs. The results revealed no remarkable findings in vital signs among the dogs used. In blood analysis, platelet counts in saline infusion groups were significantly higher than in the EPC groups within normal ranges, and no significant differences were observed except K+, Cl- and blood urea nitrogen/urea. In ELISA assay, no significant difference was observed in serum tumor necrosis factor alpha. The serum concentration of vascular endothelial growth factor was significantly higher in EPC groups than in saline groups, and interleukin 10 was significantly up-regulated in the EPC infusion group compared with other groups. In conclusion, we demonstrated that no clinical abnormalities were detected after intravenous transplantation of human EPCs in dogs. The transplanted xenogenic EPCs might be involved in anti-inflammatory and angiogenic functions in dogs.

Isolation of 151 mutants that have developmental defects from T-DNA tagging.

In order to understand the mechanisms underlying plant development, a necessary first step involves the elucidation of the functions of the genes, via the analysis of mutants that exhibit developmental defects. In this study, an activation tagging mutant library harboring 80,650 independent Arabidopsis transformants was generated in order to screen for developmental mutants. A total of 129 mutants manifesting dominant developmental abnormalities were isolated, and their T-DNA insertion loci were mapped. The activation of one or more genes adjacent to a T-DNA insertion locus was confirmed in eight dominant mutants. A gene adjacent to the right border was usually activated by the 35S enhancers. Interestingly, the transcriptional activation of multiple genes within a broad range was observed in one of the mutants, which raises the possibility that activation by the 35S enhancers was not limited strictly to a single gene. In order to gain a better understanding of sexual reproduction in higher plants, we isolated 22 mutants exhibiting defects in female gametophyte development, and determined their T-DNA insertion loci. We propose that this mutant population may prove useful in the further determination of the functions of genes that play important roles in plant development.

The 35S promoter used in a selectable marker gene of a plant transformation vector affects the expression of the transgene.

Positive selection of transgenic plants is essential during plant transformation. Thus, strong promoters are often used in selectable marker genes to ensure successful selection. Many plant transformation vectors, including pPZP family vectors, use the 35S promoter as a regulatory sequence for their selectable marker genes. We found that the 35S promoter used in a selectable marker gene affected the expression pattern of a transgene, possibly leading to a misinterpretation of the result obtained from transgenic plants. It is likely that the 35S enhancer sequence in the 35S promoter is responsible for the interference, as in the activation tagging screen. This affected expression mostly disappeared in transgenic plants generated using vectors without the 35S sequences within their T-DNA region. Therefore, we suggest that caution should be used in selecting a plant transformation vector and in the interpretation of the results obtained from transgenic approaches using vectors carrying the 35S promoter sequences within their T-DNA regions.