Stem Cells : Therapeutic Perspectives
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Transcript of Stem Cells : Therapeutic Perspectives
Stem Cells : Therapeutic Perspectives
@ Pankaj PrasadDepartment of Molecular & Human Genetics
BHU, Varanasi
“ The phenomenon of life itself negates the
boundaries that customarily divide
our
disciplines and fields.”
Hans Jonas (1966)
Stem Cells??
Definition
“ A Stem cell is a clonal, self-renewing
entity that is multipotent and thus can
regenerate several differentiated cell types.”
Embryonic Stem Cells (ESCs)
Embryonic stem cells
James A. Thomson The Thomson Laboratory
Sources of embryonic stem cells• In – vitro Fertilization (IVF)• Nuclear transfer
• The largest potential source of blastocysts for the stem cell research is from IVF clinics.
• As all fertilized eggs are not implanted, it results in a large bank of “excess” blastocysts, stored in freezers around the globe.
Somatic Cell Nuclear Transfer (SCNT)
Adult stem cells
Sources of adult Stem Cells
Induced Pluripotent Stem (iPS) cells
Shinya Yamanaka, M.D., Ph.D.Professor, Institute for Frontier Medical Sciences
Next generation iPS cells
Kevin C. EgganHarvard University Department of Stem Cell and Regenerative BiologyStowers Medical Institute
Epigenetic reprogramming
Konard Hochedlinger had shown that it is possible to create mouse iPS cells using an adenovirus in place of the retroviruses previously used. Harvard University Department of
Stem Cell and Regenerative BiologyMassachusetts General Hospital
Transdifferentiation Refers to the
conversion of one differentiated cell type to another and considered a subset of metaplasia.
Faculty of Arts and Sciences, Harvard UniversityHoward Hughes Medical Institute
Cancer Stem Cells (CSCs)
Cancer stem cellsCurrent cancer therapies may fail because cancer stem cells have not
been eradicated.
leave patients prone to recurrence.
Pulling out a weed while leaving the roots.
Origin of cancer stem cells
Treatment
Stem cell niches
Scadden D.T. Nature 2006
Scadden D.T. Nature 2006
Quiescence stem cells
Quiescence
Slow cell cycling of stem cells
Unresponsive to many chemotherapeutics that typically target
rapidly proliferative cells
Zebra fish : Model system for stem cell research
Harvard Magazine
Role in basic research
NIH, U.S.
Stem cell research centers
Stem cell research in India
Stem cells Banks
Major BMT centers in India
Bone Marrow Transplantation (2008Bone Mar08
EthicsMoral values
Law
Peer review
“Human reproductive cloning
should not be practiced. It is dangerous and likely to fail.”
Scientific and medical aspects of human reproductive cloning. National Academic Press, 2005.
Conclusion• Stem cell research is being pursued in the
hope of achieving major medical breakthroughs.
• Currently only a few diseases are treatable with stem cell therapies because scientists can regenerate only a few types of tissues.
• Future fundings will provide more insights into the mechanisms regulating the stem cell pluripotency.
References
Thanking you