Courtesy of engineering.vcu.edu
 Goy-Gol Landscape, Azerbaijan. Courtesy of hardasan.com
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 Courtesy of medicineworld.org  Courtesy of medicineworld.org A jumping gene first identified in a cabbageeating moth may provide a safer, targetspecific alternative to viruses for gene therapy, researchers say.In addition to piggyBac, researchers looked at what was believed to be the most efficient transposon in mammalian cells, hyperactive Sleeping Beauty, first found “asleep” in fish. They also looked at Tol2, another fish transposon, and Mos1, found in insects. The piggyBac transposon, which has close relatives in the human genome, is widely used to genetically modify insects. Sleeping Beauty has been used to correct hereditary diseases, including hemophilia, in a mouse model. For this study, researchers used transposons to deliver an antibiotic resistant gene. They found that while piggyBac might be less efficient than a virus, it puts Sleeping Beauty to shame when it comes to making cells antibioticresistant. Source:  Courtesy of medicineworld.org  Courtesy of medicineworld.org  Courtesy of medicineworld.org |
 Dr. A. Nagy. Courtesy of CTV.ca ScienceDaily (Mar. 1, 2009) — Mount Sinai Hospital's Dr. Andras Nagy discovered a new method of creating stem cells that could lead to possible cures for devastating diseases including spinal cord injury, macular degeneration, diabetes and Parkinson's disease. The study, published by Nature, accelerates stem cell technology and provides a road map for new clinical approaches to regenerative medicine. "We hope that these stem cells will form the basis for treatment for many diseases and conditions that are currently considered incurable," said Dr. Nagy, Senior Investigator at the Samuel Lunenfeld Research Institute of Mount Sinai Hospital, Investigator at the McEwen Centre for Regenerative Medicine, and Canada Research Chair in Stem Cells and Regeneration. "This new method of generating stem cells does not require embryos as starting points and could be used to generate cells from many adult tissues such as a patient's own skin cells." Read the rest here"
 Courtesy of faz.net Links: |
genes in the human body, but found only a fraction of that -- less than 30,000.
 Professor Austin Smith is the Chair of The main objective of this group is to characterise the cellular and molecular mechanisms governing the self-renewal and differentiation of multipotential embryo stem cells, of mouse, rat and human origin. Stem cells are defined by the ability both to produce identical daughter cells (self-renewal), and to produce progeny with more restricted fates (commitment and differentiation). This property of stem cells underpins growth and diversification during development and sustains homeostasis and repair processes throughout adult life. Source:  Developing a technique for generation Stem Cell Science plc has announced its groundbreaking research, developing a technique for generation of authentic embryonic stem (ES: 5.43, 0, 0%) cells from rats. It is an international research and development company focused on the commercial application of stem cell biology technologies for drug discovery and regenerative medicine research. The research was published in the journal Cell is the first of its kind that demonstrates germ-line transmission from rat ES cells. It makes use of a technology licensed exclusively to SCS by the University of Edinburgh and developed by Professor Austin Smith and his team, now at Cambridge University. the new technique would be generating consistently appropriate and stable at ES cells, which can be used to create genetically modified animals for medical, academic and pharmaceutical research. According to Dr Alastair Riddell, Chief Executive Officer of Stem Cell Sciences, the new technique would pave way for more effective drug discovery Source: |
DIFFERENTIATION ARREST BY HYPOXIA
By: Qun Lin, Yi-Jang Lee and Zhong Yun
The stem cell niche is a unique tissue microenvironment that regulates the selfrenewal and differentiation of stem cells.Although several stromal cells and molecular pathways have been identified, the microenvironment of the stem cell niche
remains largely unclear. Recent evidence suggests that stem cells are localized in areas with low oxygen. We have hypothesized that hypoxia maintains the that hypoxia reversibly arrests preadipocytes in an undifferentiated state. Consistent with this observation, hypoxia maintains the expression of pref-1, a key stem/precursor cell gene that negatively regulates adipogenic differentiation. We further demonstrate that the hypoxia-inducible factor-1 (HIF-1) constitutes an important mechanism for the inhibition of adipogenic differentiation by hypoxia. Our findings suggest hypoxia in the stem cell niche is critical for the maintenance of the undifferentiated stem or precursor cell phenotype.
Source:
DIFFERENTIATION ARREST BY HYPOXIA
self-renew extensively, and to initiate, sustain, or regenerate disease.
By:Piu Wong, Masayuki Iwasaki, Tim C.P. Somervaille, Chai Wai Eric So, and Michael L. Cleary1
Leukemia stem cells (LSCs) comprise a functionally distinct subpopulation of leukemic cells with the ability to self-renew extensively, and to initiate, sustain, or regenerate disease. In acute myeloid leukemia (AML), LSCs are generally considered to be rare upstream cells that arise out of the normal hematopoietic stem cell (HSC) or primitive progenitor compartments, and are organized in a hierarchy based on quantitative differences in their self-renewal potentials (Passegue and Weisman 2005).
Source:
stem cell potential leukemia MLL is an essential and rate-limiting ...
Julius Friedrich Cohnheim was a pioneer of experimental pathology (Born 20 July 1839; died 1884 )
Julius Friedrich Cohnheim .
Photo courtesy of todayinsci.com
Cohnheim proposed the first great theory of cancer's origin, the theory of embryonal rests. He thought more germ cells are produced with a developing embryo than are needed to form any given part and that cancer's development involves this excess material.
Source:
Cohnheim in Todayinsci
THE REALITY OF BLASTOCYST TRANSFERS
The mouse feeder cells were an important ingredient in the mix of culture materials required to keep stem cells in their undifferentiated "blank slate" state. Embryonic stem cells are capable of forming any of the 220 tissues and cells in the human body and, in culture, are constantly trying to migrate down different developmental pathways. Maintaining stock cultures in their undifferentiated state is critical.
It is a well-known curiosity that only a minority of cells within a tumour are typically responsible for tumour growth and development. >
Unlike most other structures in the adult brain, the hippocampus is able to produce new neurons (neurogenesis) throughout adult life as it contains a population of neural stem cells.
By: Panagiotis A. Tsonis
A recent study by Chen et al. characterizes the small molecule reversine, a substituted purine analog, as a signal for the dedifferentiation of myotubes (formed from a myoblastic cell line) back into progenitor cells that can then differentiate, under appropriate conditions, into osteoblasts or adipocytes. The authors speculate that the process may involve protein kinases and that further work will identify the spe-cific kinase or other molecules to which reversine binds. This work is of extraordinary interest and may have landmark importance to regeneration research (i.e., reforming nerves, limbs, and organs) and clinical medicine.
Figure 1. Transdifferentiation in urodele limb
and lens regeneration and in a committed murine cell line.
Courtesy of molinterv.aspetjournals.org
Figure 1. Transdifferentiation in urodele limb and lens regeneration and in a committed murine cell line. After amputation of the newt limb (or tail) the intact terminally differentiated cells (such as, mesenchymal cells, myotubes, nervous tissue, bone, or cartilage) dedifferentiate by losing the characteristics of their origin. This dedifferentiation process produces the blastema cells, which then redifferentiate to reconstitute the lost limb. After lentectomy, the dorsal iris pigment epithelial cells lose their pigments and become dedifferentiated cells, which consequently regenerate a perfect lens. A small molecule, reversine, is able to induce dedifferentiation of myotubes formed by murine C2C12 cells. This dedifferentiation produces mesenchymal progenitor cells that are able to differentiate to different cell types, such as adipocytes and osteoblasts. According to this scheme, the reversine produced progenitor cells could be analogous to the blastema cells or other dedifferentiated cells used during regeneration in urodeles.
Source:
Reversine: an easy source of cells to regenerate tissues damaged by disease or injury.A chemical could switch adult cells from one type to another.
Chemists in California have found a synthetic molecule that seems to reprogramme adult cells to make them more like youthful ones. If the discovery pans out, it could provide an easy source of cells to regenerate tissues damaged by disease or injury.
Source:
Tumors are caricatures of the organ in which they arise
It is becoming apparent that tumors are caricatures of the organ in which they arise. The cancer cells in a tumor are arranged in a hierarchy and contain a minority population of cancer stem cells that drive tumor growth while the majority of the cancer cells are unable to do so. Normal stem cells and cancer stem cells maintain themselves through a process called self-renewal. The cancer stem cells are responsible for the growth and spread of tumors. Expansion of normal stem cells is under genetic constraints. Cancer stem cells have escaped these limitations on expansion resulting in expansion of the self-renewing cell populations. The goals of this meeting are to understand present the most current research into the cellular and molecular biology of cancer stem cells. Topics that will be explored in this meeting are the cancer stem cell niche, the cell of origin of cancer stem cells, the regulation of stem cell self-renewal in normal stem cells and cancer, and cancer stem cells as therapeutic targets.
Source:
& Stem cells
Royan Institute (Tehran/Iran):Department of Stem Cells
Members:
Narges Zare Mehrjardi (Neuroscience PhD student)
Maryam Hatami (Cell & Molecular Biology MSc)
Sahar Kiani (Physiology PhD student)
This group has been committed to exploring the biology and therapeutic potential of stem cells for the treatment of neurological disorders. For this purpose we focused on differentiation, transplantation, tissue engineering and signaling of neuron derived stem cell. Recently we transplanted differentiated neural tube from human embryonic stem cell to spinal cord injured rat.
Stem cell research will increase our understanding of the nervous system and may allow us to develop treatments for currently incurable brain and spinal cord diseases and injuries. In addition, the stem cells should be used for stem cell research aimed at the detailed study of mechanisms of neural differentiation, transdifferentiation, genetic and environmental signals that direct specialization of the cells into particular cell types. Breakthrough studies have recently rejected the long-standing belief that neuronal tissue is incapable of regeneration.
The successful engraftment of neural stem cells following implantation into the brain of rodent models has demonstrated the potential of this cell type. The development of neural stem cell biology requires specific research tools that allow the isolation, expansion and characterization of this stem cell type. In addition, the availability of reagents for the characterization of progenitor cells is critical for the analysis of their therapeutic potential. Neural stem cells can be derived from embryonic sources, or from specialized niches in the adult nervous system. Because they have the capacity to generate all of the multiple cell types found in the brain and spinal cord, neural stem cells have the potential to repair tissue injured by trauma or disease.
Source:
Royan Institute & Nerves System
hESC-derived neurons. Courtesy of
royaninstitute.org
The discovery that neurons, astrocytes and oligodendrocytes arise from neural stem cells located in specific regions of the central nervous system has important clinical applications for the treatment of life-threatening, neuronal diseases, including Parkinson’s Disease.
Links:
What are embryonic stem cells?
Eyewitness accounts from inside the booming trade in fetal body parts
GeneExpression Systems, Inc. is a biotech company that develops and markets differential gene profiling technology for down stream study of gene expression, regulation, diagnostic, predictive toxicology and therapeutic purposes. The company is situated in the Greater Boston area biotech hub and commercializes proprietary gene expression kits, services and technologies to accelerate and enhance the discovery of new markers. für dessen Dechiffrierung ist die Chromatin-Immunpräzipitation (ChIP) für dessen Dechiffrierung ist die Chromatin-Immunpräzipitation(ChIP). Für deren Analyse wurden jetzt neue effiziente Parallelsequenziermethoden(ChIPseq) entwickelt, die herkömmlichen Mikroarrays Konkurrenz machen werden. Source:  Chip sequencing. Courtesy of wikimedia.org
Dr. Michael White, a biochemist and a postdoctoral fellow in the Department of Genetics and the Center for Genome Sciences at the Washington University School of Medicine With the latest DNA sequencing technology, you can dispense with building a DNA chip. You no longer need to make probes, put fluorescent chemicals on your DNA, and see which probes your DNA sample sticks to. Instead, you just take your DNA sample sequence it - you can now find out directly just exactly what DNA is in that small, clear drop of liquid Source: Source:  Courtesy of genetics.utah.edu  Courtesy of genetics.utah.edu  Courtesy of nature.com Source: Natalie DeWitt  Courtesy of nature.com Source: Natalie DeWitt Using a massively parallel sequencing approach, the Illumina Genome Analyzer (GA) can generate billions of bases of high quality sequence data in a single run. The system uses Solexa sequencing technology and novel reversible terminator chemistry, optimized to achieve unprecedented levels of cost effectiveness and throughput.  DNA Technologies, Solexa Test Souce:  The latest next-generation sequencing
Link & source: Name of Videos from left to right: 1)Umbilical Cord Stem Cells 2)Stem Cell Video |
Working paper prepared by: Hutton Oddy, John McEwan, Brian Dalrymple, Jill Maddox, Frank Nicholas, Chris Warkup and Alex Clop. 23 November 2006 The sheep genomics community is keen to sequence the sheep genome. This will facilitate research to improve the productivity of sheep and the health of the environments in which sheep are managed. It will also facilitate research using sheep as a model for studies of human physiology and disease. Outcomes of the sequencing strategy proposed, in addition to sheep specific genomic sequence,include at least 1.4 million ordered SNPs for use in sheep genetic improvement,and information that will assist the assembly of the bovine genome.  The Genome Analyzer. Courtesy of illumina.com  PyroMark™Q24 System.Courtesy of pyrosequencing.com  PyroMark Vacuum Prep Workstation.Courtesy of pyrosequencing.com  Pyro Q-CpG can be performed  Pyro Q-CpG Software has been Pyrosequencing (Roche platform) involves the use of a pyrophosphate molecule, released following nucleotide incorporation by DNA polymerase, to propagate reactions that ultimately produce light. Illumina’s sequencing-by-synthesis involves the use of four differently labelled fluorescent nucleotides that have their 3’-OH groups chemically inactivated to ensure only a single base is incorporated per cycle. Each base incorporation cycle is followed by an imaging step to identify the base incorporated, and a chemical stepthat removes the fluorescent group and eblocks the 3’ end for the next base incorporation cycle. The SOLiD sequencer (Applied Biosystems) uses a ligation-based sequencing process that starts by annealing a universal sequencing primer that is complementary to the SOLiD specific adaptors on the library fragments. Source:  Illumina /Solexa Genome Analyzer II.  Tearless Onion.Courtesy of imageshack.us  Stem cells. Courtesy of viacord.com  Stem cells. Courtesy of virtualrosario.com  Stem cells. Courtesy of virtualrosario.com  CELULAS MADRE BOLIVIA. Courtesy of celulasmadrebolivia.com  Professor Ivan Bertoncello. Courtesy of stemcellcentre.edu.au Associate Professor Ivan Bertoncello leads the Adult Lung Stem Cell Laboratory at the Australian Stem Cell Centre and is also responsible for the development and co-ordination of training programs in stem cell technologies for the Australian Stem Cell Centre. He holds honorary academic appointments in the Department of Anatomy and Cell Biology, Monash University, and the Department of Pathology, University of Melbourne, and is a former Fellow of the Alexander von Humboldt Foundation (Germany). Associate Professor Bertoncello’s pioneering work in the development of Rhodamine 123 and Hoechst 33342 dye-based cell separative strategies for haemopoietic stem cell isolation, and his laboratory’s definitive study of haemopoietic stem cell cycling and turnover has provided the field with powerful tools for the analysis of haemopoietic stem cells leading to a re-evaluation of models of haemopoietic stem cell organization and function. Overview Refining the human embryonic stem cell phenotype Thus far, our research, has demonstrated that we can isolate viable pluripotent (Oct-4+) human ES cells from a heterogenous mixture of cells by selecting for two surface markers. This is important as this methodology provides a facile means for the separation of Oct-4+ cells from Oct-4– human ES cells without insertion of selectable markers. We have transcriptionally profiled subpopulations of hESC delineated using these cell surface markers. Current projects focus on gaining a better understanding of both the maintenance of the stem cell state and the decisions hESC make when becoming committed to a specific lineage. Source: hES cell culture is generally considered more difficult than mouse ES cell culture. Mouse ES cells are often cultured on feeders made of immortal MEF cell lines, while hES cells need to be cultured on primary MEF cells. We will teach you to derive primary MEF cells in this course. hES cells are more difficult than mouse ES cells to culture, recover from a thaw, or passage. If you have mouse ES cell experience, but no hES cell experience, this course will offer you a lot of new information and technical training vital to the successful propagation of your hES cells. To maintain pluripotency, mES cells are cultured on feeder cells; either MEFs, STO fibroblast cell line; or for feeder-free mES clones on gelatinized plates in the presence of leukaemia inhibitory factor (LIF). Growth media and culture conditions should be used as suggested for each ES cell line. Mitotically inactivated MEFs are used as feeders only for a long-term culture of R1 ES cells [1], typically before and after cryopreservation. Otherwise, culture of R1 ES cells for electroporation and during the selection is done on gelatinized plates. MEF cells can be made from any strain of mice including transgenic mice that express bacterial neomycin or hygromycin genes depending on the choice of selectable markers used for altering the ES cell genome. NeoR and HygroR (JR2356, JR2354) as well as the DR-4 strain (Jackson Laboratories #003208) bearing neo, puro, hyg resistance genes and a deletion of the Hprt gene are available from Jackson Laboratories. Detailed protocols for preparation of MEF stocks and mitomycin C treated feeders for ES cell culture are presented in many publications (e.g. [2]). Our brief protocols Source: Hilton Head Workshop EMBO Practical Course on Differential Proteomics From 2-D Gel Electrophoresis to Mass Spectrometry According to John M. Greally, Associate Professor, Departments of Medicine and Molecular Genetics, Albert Einstein College of Medicine, Bronx, NY, the term epigenomics can be used to describe two areas of research: (i) the study of epigenetic regulation of gene expression using high-throughput techniques or (ii) the study of the infl uence of DNA sequence on epigenetic regulation. Human diseases in which epigenetic mechanisms are thought to play a part include aging, cancer, obesity, type 2 diabetes, and mental disorders. Source: Epigenetics may indeed hold answers to many mysteries that classical genetic approaches have been unable to solve, said Dr. Arturas Petronis, an associate professor of psychiatry at the Center for Addiction and Mental Health at the University of Toronto. For example, why does one identical twin develop schizophrenia and not the other? Why do certain disease genes seem to affect or "penetrate" some people more than others? Why do complex diseases like autism turn up in more boys than girls?  Les expériences d’immunoprécipitation Source: Dr. M. Bornens Centre National de la Recherche Scientifique, Gif-sur-Yvette, France. A basic question in studies of the genesis of cell polarity is whether the polarity is an intrinsic and permanent property of cells or whether it is externally imposed by signals at the cell periphery Dr. Andreas Wodarz Dept. of Stem Cell Biology GZMB Justus-von-Liebig-Weg 11 37077 Göttingen Germany One important aspect of asymmetric cell division is the establishment of an intrinsic polarity which is the prerequisite for the asymmetric localization of proteins and mRNAs that serve as cell fate determinants. Our model system for the asymmetric division of stem cells is the embryonic neuroblast of Drosophila. Here we study the function of genes that control cell polarity, asymmetric localization of cell fate determinants and orientation of the mitotic spindle. The knowledge obtained in the Drosophila system has stimulated intense research on the participation of the orthologous genes and proteins in the asymmetric division of vertebrate stem cells. |
1)SNP Chip for the Sheep Genome
2)Stammzellen (from SynergyMarketing)
 Dr Stefan Przyborski, Durham University |
Um die so gennaten induzierten pluripotenten Stammzellen (kurz:iPS) zu erzeugen, hatte das team um Shinya Yamanka weder Eizellen noch Embryonen benoetigt. Um sie in aehnliche Alleskoenner zu verwandeln, wie es die embryonalen Stammzellen sind, genuegte es, vier Gene in das Erbgut der Hautzellen einzuschleusen: Oct4, Sox2, C-Myc and Klf4. Der Haken daran war nur: Viele der Tiere, denen man iPS-Zellen implantiert hatte, erkrankten wenige Wochen spaeter an Krebs.
Die kanadischen Forscher schleusten ebenfalls alle vier Gene zusammen mit dem Transposon in Bindegewebszellen des Menschen und der Maus ein. Ihnen gelang es zudem, die Genfähre zusammen mit den eingeschleusten Genen komplett aus dem Erbgut der induzierten Stammzellen wieder herauszuschneiden. Bei der Methode von Kaji ohne das Transposon verbleiben nach dem Herausschneiden noch Reste der Genfähre im Erbgut.
Gene Delivery Technology — The Sleeping Beauty Transposon™ System (SBTS) is a non-viral carrier of genetic information that can insert a gene into vertebrate (human) chromosomes in order to confer a new function or replace a defective gene. Four patent applications regarding the use of this transposon for introducing new DNA into the chromosomes of a cell have been filed, with the base patent* issued in December 2002. * United States Patent 6,489,458; Hackett , et al. December 3, 2002; DNA-based transposon system for the introduction of nucleic acid into DNA of a cell. A Novel Gene Transfer System : The SBTS (SB Therapeutics) shows promise as a long-lasting, safe way to insert genes into the chromosomes of cells without using a viral vector. The Sleeping Beauty Transposon System is a dynamic biological device consisting of: • The SB Transposon. • The SB Transposase – specific to the SB Transposon. • A therapeutic gene. The Sleeping Beauty transposon carrying the therapeutic gene is "cut" out of the plasmid vector by the engine of this machine (the transposase) and then "pasted" directly into the chromosome. The operation of this biological nano machine is unique and proprietary to DGI. Source: |
Name of Videos from left to right:
1)Jerome Zack: Creating iPS Cells
2)Mark Mercola: Differentiating embryonic stem cells into adult tissues
Stochasticity and the Molecular Mechanisms of Induced Pluripotency Ben D. MacArthur, Colin P. Please, and Richard O. C. Oreffo1 The generation of induced pluripotent stem cells from adult somatic cells by ectopic expression of key transcription factors holds significant medical promise. However, current techniques for inducing pluripotency rely on viral infection and are therefore not, at present, viable within a clinical setting. Thus, there is now a need to better understand the molecular basis of stem cell pluripotency and lineage specification in order to investigate alternative methods to induce pluripotency for clinical application. However, the complexity of the underlying molecular circuitry makes this a conceptually difficult task. In order to address these issues, we considered a computational model of transcriptional control of cell fate specification. The model comprises two mutually interacting sub-circuits: a central pluripotency circuit consisting of interactions between stem-cell specific transcription factors OCT4, SOX2 and NANOG coupled to a differentiation circuit consisting of interactions between lineage-specifying master genes. ...The flexibility in the differentiation hierarchy is commonly known as lineage plasticity [3] and is perhaps most dramatically demonstrated by molecular reprogramming of adult somatic cells into so-called induced pluripotent stem (iPS) cells, which express the genetic and phenotypic characteristics of pluripotent ES cells. Since iPS cells potentially provide a patient-specific source of pluripotent stem cells they possess significant clinical potential.Furthermore, since they are derived from adult somatic cells which are easily harvested through biopsy, the generation and clinical use of iPS cells is not associated with the same ethical controversies as human ES cells, although they are associated with significant alternative ethical issues. Source: |
 Professor Rudolf Jaenisch. Courtesy of scienceprogress.org LA JOLLA, Calif. & CAMBRIDGE, Mass.--(BUSINESS WIRE)--Fate Therapeutics, Inc. announced today that Dr. Rudolf Jaenisch, M.D., founding member of the Whitehead Institute for Biomedical Research and professor in the Department of Biology, Massachusetts Institute of Technology, has joined the Company’s internationally recognized team of scientific founders dedicated to understanding stem cell biology in human physiology and disease. Dr. Jaenisch is credited with being one of the first to discover the revolutionary mechanisms for “reprogramming” fully-mature adult cells to a stem-like state. The creation of these “reprogrammed” cells, known as induced pluripotent stem (iPS) cells, provides numerous advantages over stem cells sourced from human embryos and has ushered in a new paradigm in stem cell research for modeling human diseases, discovering and testing conventional pharmaceuticals and developing personalized cell replacement therapies. Source:  Professor Rudolf Jaenisch. Courtesy of mdc-berlin.de Links:
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