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Jason Hipp

Publications and source records attributed to Jason Hipp.

3 recordsLinked to original sources

GeneChips in stem cell research.

An understanding of the genes and signaling networks responsible for stem cell growth and differentiation will be essential for their ultimate therapeutic application. GeneChips are miniature platforms of nucleotides capable of monitoring the expression levels of almost every known and unknown gene. Performing a GeneChip experiment is like snapping a picture of a cell's mRNA (transcripts), thus giving a static view and measurement of gene expression inside the cell. Taking multiple "pictures" of stem cells as they grow and differentiate will provide insight into the genetic mechanisms of "stemness" or can be used to create "transcriptional signatures" to assess differentiation and variability between stem cell lines. The first half of this chapter covers the many components involved in a GeneChip experiment, illustrating the many variables at each step and describing a protocol for analysis that is inexpensive and requires minimal computer skills. The chapter then describes how researchers are currently applying GeneChips to stem cell biology. We conclude that the true potential of GeneChip technology lies in the in silico analysis-their integration and comparison of diverse data sets, where the biological questions are the driving force in the analysis.

Animals↗

Tissue engineering, stem cells, cloning, and parthenogenesis: new paradigms for therapy.

: BACKGROUND: Patients suffering from diseased and injured organs may be treated with transplanted organs. However, there is a severe shortage of donor organs which is worsening yearly due to the aging population. Scientists in the field of tissue engineering apply the principles of cell transplantation, materials science, and bioengineering to construct biological substitutes that will restore and maintain normal function in diseased and injured tissues. Both therapeutic cloning (nucleus from a donor cell is transferred into an enucleated oocyte), and parthenogenesis (oocyte is activated and stimulated to divide), permit extraction of pluripotent embryonic stem cells, and offer a potentially limitless source of cells for tissue engineering applications. The stem cell field is also advancing rapidly, opening new options for therapy. The present article reviews recent progress in tissue engineering and describes applications of these new technologies that may offer novel therapies for patients with end-stage organ failure.

Journal Article↗

Derivation and comparative assessment of retinal pigment epithelium from human embryonic stem cells using transcriptomics.

Human stem-cell derivatives are likely to play an important role in the future of regenerative medicine. Evaluation and comparison to their in vivo counterparts is critical for assessment of their therapeutic potential. Transcriptomics was used to compare a new differentiation derivative of human embryonic stem (hES) cells--retinal pigment epithelium (RPE)--to human fetal RPE. Several hES cell lines were differentiated into putative RPE, which expressed RPEspecific molecular markers and was capable of phagocytosis, an important RPE function. Isolated hES cell-derived RPE was able to transdifferentiate into cells of neuronal lineage and redifferentiate into RPE-like cells through multiple passages (>30 Population doublings). Gene expression profiling demonstrated their higher similarity to primary RPE tissue than of existing human RPE cell lines D407 and ARPE-19, which has been shown to attenuate loss of visual function in animals. This is the first report of the isolation and characterization of putative RPE cells from hES cells, as well as the first application of transcriptomics to assess embryonic stem-cell derivatives and their in vivo counterparts--a "differentiomics" outlook. We describe for the first time, a differentiation system that does not require coculture with animal cells or factors, thus allowing the production of zoonoses-free RPE cells suitable for subretinal transplantation in patients with retinal degenerative diseases. With the further development of therapeutic cloning, or the creation of the banks of homozygous human leucocyte antigen (HLA) hES cells using parthenogenesis, RPE lines could be generated to overcome the problem of immune rejection and could be one of the nearest term applications of stem-cell technology.

Cell Differentiation↗