Talk:2009 Lab 10

Stem Cells

--Antonio Lee 15:22, 31 October 2009 (EST) Hi Mark, I have marked the Lab10 Questions and indicated marks on students' pages. Thanks for the opportunity, I enjoyed it very much!

Practical Preparation

--Antonio Lee 10:33, 8 October 2009 (EST) Hi Mark, I have uploaded Lab 10 Assessment Questions on both the Lab Page and Student's Page. I will make myself down to the lab at 12:45-50 this afternoon. Thanks.

--Antonio Lee 11:26, 2 October 2009 (EST) Hi Mark, I have updated each group discussion boards with assigned links and PDFs (uploaded). Please take a look and let me know if they are okay. I will put couple of assessment questions before the lab next week. Thanks,

--Antonio Lee 09:22, 2 October 2009 (EST):Hi Mark, Yes, I'd definitely like to provide the readings beforehand and encourage them to read their paper beforehand. I will try to paste each paper on assigned group's discussion board. I am sure not all students will read their papers before hand and I appreciate during 15-20 minutes it is impossible to digest the full content of the paper. That is why I thought each student from the group (of 4 students) can address 1 question only during the class time (essentially, Intro, M&M, Results or Discussion). Then each student can present their bits in couple of minutes to make up the whole story the paper is saying?

I will also make sure to leave ~15 mins at the end for them. Thanks,

--Mark Hill 06:57, 2 October 2009 (EST) Hi Antonio, looks good so far. I have not yet checked the length of your readings for the group work, but you may consider how long it will take them to do this. Do you want to provide the readings to the groups beforehand? If so, you can paste it onto each group discussion page and see whether some read the paper before the lab (some listed papers are not accessible from outside UNSW). Also, the students will require some time (15 minutes or so) at the end of the lab to discuss their ongoing group project.

--Antonio Lee 21:13, 1 October 2009 (EST) Hello Mark, I have put the materials on the Lab Page. Could you take a look and let me know if the format/use of external links are appropriate? I will also set 2-3 easy questions and post them on the page for the students before the lab next week. Thanks,

--Mark Hill 11:48, 18 September 2009 (EST) I now have permission for this image if you want to use the mitochondrial example. Swapping_mitochondrial_DNA_mammalian_oocytes

--Antonio Lee 10:34, 18 September 2009 (EST)Thanks Mark, just trying to get used to in using this Wiki - it's my first. I take all of your comments on board and will work on those over the weekend. Thanks.

--Mark Hill 09:56, 18 September 2009 (EST) Yes I do fine email back n forth a little tedious. Lets work together here. Your class plan looks fine to me so far.

Title: Therapeutic Use of Stem Cells - Practical Hurdles & Ethical Issues

--Mark Hill 10:10, 18 September 2009 (EST) I have now renamed the actual practical page to this title. Feel free to change any content yourself. I think the students also need a good but brief description of new terms you will be using in your presentation. See example Muscle Lab 7 Terms.

Structure

--Mark Hill 09:59, 18 September 2009 (EST) These don't have to be power points, but if you do use, need to convert to PDF and link to the lab page. I usually prepare 2 PDF versions (1 slide /page and 4 slides / page printing)

• 15 min: (PPT) Brief introduction on Embyonic and Adult Stem cells (I will borrow some of your slides and incorporate my own) & their potentials as new therapeutic agents.
• 15 min: (PPT) Outline our own work - Developing better stem cell transplantation strategy using chemotherapy & genetically engineered chemo-resistant stem cells for treating muscle diseases (muscular dystrophies).

--Mark Hill 10:03, 18 September 2009 (EST) You might also consider using this very recent example for Mitochondrial Disease as well, because its very current, therapeutically relevant and just interesting new application, and the paper in nature also has an illustrated editorial. PMID: 19710649 | Nature Article | Nature editorial

• 20 min: (Web Search Exercise) Each group of 4 students (pre-existing groups) will be given a recent news article on stem cell break-through / advancement with clinical/therapeutic implication (I will pre-select these from news feeds and post them on the web-site 1 week before the lab, one assigned to each group). They will do web-search exercise to prepare answers / comments for each of the following questions regarding their news piece.

Q1. What is the background to the existing problem / disease condition?

Q2. What approach / method did the research team take to tackle / improve the problem?

Q3. What was the breakthrough / major advancement OR failure / drawback? and why might this be of significance?

Q4. What are the next steps in moving forward? What are the next or new hurdles to overcome?

Q5. Are there any ethical / moral issues or concerns in your view?

Suggestive format will be that each of the 4 students will prepare a paragraph-long answer to 1 of 4 questions (from Q1 ~ Q4) using web-search. Each student then can express their view on Q5 verbally during discussion. They can type-up the answers as they go (or copy and paste relevant information from web-pages and include the http address for reference).

50-60 min: (Student Participation) Each group will present their answers (5 min) followed by questions/discussions (5 min).

I will have prepared my own version of "answers" for each of the news piece to facilitate.

If you require some sort of assessable material, how about if we ask the students to hand-in the write-up of their answers (Q1 ~ 4), say by the following Thursday? - to give them little more time to polish their paragraphs?

--Mark Hill 11:50, 18 September 2009 (EST) I have only been setting relatively easy questions to mark as part of their ongoing assessment. ANAT2341_2009_Students#Progressive_Assessment

That is all, and by all means, if you find making comments on e-mail laborious, do drop by (or I can come down to your office) and we can have a chat.

Previous Webpage

--Mark Hill 11:44, 18 September 2009 (EST) Feel free to use what you need from below.

File:Week1 cartoon600.jpg

Week 1 Human Development - Embryonic Stem Cells

Inner cell mass

The term "stem cell" is used so freely these days in many different forums that it is difficult sometimes understand without context what scientists, politicians, ethicists and commentators are discussing. This lecture will focus on the cell biology of stem cells and the current research on growing and differentiating theses cells.

Background information can also be found at UNSW Embryology Stem Cells and Week 1 Development.

Why are they in the News?

• Scientific and Ethical
• Therapeutic uses
• Issues relating to human cloning
• Use of excess human eggs/sperm for research purposes
• Availability of human stem cell lines

What can they be used for?

• Generation of “knock out” mice
• Studying regulation of cell differentiation in development
• Therapeutic uses?
• Genetic disease
• Neurodegenerative
• Injury

PubMed

• Medline Search “stem cell”
  • 2002 - 110,920
  • 2004 - 128,485
  • 2005 - 140,966
  • 2006 - 154,176

Research that led to Stem Cells

• Human Diseases
  • Generation of “knock out” mice
• Human Development
  • Studying regulation of cell differentiation in development
• Human Reproduction
  • Disorders, sterility

Tissue Stem Cells

• differentiated cells have short life spans continually replaced
• blood cells, epithelial cells of skin and digestive tract
• fully differentiated cells do not proliferate
• proliferation of less differentiated- stem cells
• produce daughter cells that either differentiate or remain as stem cells

Blood Cells

Hematopoietic and stromal cell differentiation

• All different types of blood cells develop from a pluripotent stem cell in bone marrow
• Precursors of differentiated cells undergo several rounds of cell division as they mature
  • proliferation ceases at terminal stages of differentiation

Embryonic Stem Cells

File:Progenitor and stem cell cartoon.jpg

Difference between a Progenitor and Stem Cell

NIH - What are embryonic stem cells?

Pluripotent Stem Cells

• What is a stem cell- Pluripotent
• Pluripotent - to describe stem cells that can give rise to cells derived from all 3 embryonic germ layers
  • Mesoderm
  • Endoderm
  • Ectoderm
• layers are embryonic source of all cells of the body

Blastocyst

• hollow structure composed of about 100 cells surrounding an inner cavity
• Only ES cells, which form inner cell mass, actually form the embryo.
• ES cells can be removed from the blastocyst and grown on lethally irradiated “feeder cells.” (See E. Robertson et al., 1986, Nature 323:445)

Stem Cell Definition

• cell that has ability to divide for indefinite periods
• self replicate
• throughout life of organism
• stem cells can differentiate
  • conditions, signals
• to the many different cell types

Chimeric Mouse

• ES or teratocarcinoma
• shows that stem cells can combine with cells of a normal blastocyst to form a healthy chimeric mouse

Embryoid Bodies

• spheroid cellular tissue culture structure
• mouse and human ES cells have the capacity to undergo controlled differentiation
• recapitulate some aspects of early development
  • regional-specific differentiation program
  • derivatives of all three embryonic germ layers

Historic References

Mouse

• Isolation of a pluripotent cell line from early mouse embryos cultured in medium conditioned by teratocarcinoma stem cells. Martin GR. Proc Natl Acad Sci U S A. 1981 Dec;78(12):7634-8.
• Characterization of a pluripotent stem cell line derived from a mouse embryo. Wobus AM, Holzhausen H, Jakel P, Schoneich J. Exp Cell Res. 1984 May;152(1):212-9.
• Transgenesis by means of blastocyst-derived embryonic stem cell lines Proc Natl Acad Sci U S A. 1986 Dec;83(23):9065-9. Gossler A, Doetschman T, Korn R, Serfling E, Kemler R.

Pig and Sheep

Derivation of pluripotent, embryonic cell lines from the pig and sheep. Notarianni E, Galli C, Laurie S, Moor RM, Evans MJ. J Reprod Fertil Suppl. 1991;43:255-60.

Primate

Isolation of a primate embryonic stem cell line. Thomson JA, Kalishman J, Golos TG, Durning M, Harris CP, Becker RA, Hearn JP. Proc Natl Acad Sci U S A. 1995 Aug 15;92(17):7844-8.

Human

Embryonic stem cell lines derived from human blastocysts. Thomson JA, Itskovitz-Eldor J, Shapiro SS, Waknitz MA, Swiergiel JJ, Marshall VS, Jones JM. Science. 1998 Nov 6;282(5391):1145-7.

Stem Cell Lines ATCC - Embryonic Stem cell lines

Timeline of Human Embryonic Stem Cell Research

• 1878 First reported attempts to fertilize mammalian eggs outside the body
• 1959 First report of animals (rabbits) produced through IVF in the United States
• 1960's Studies of teratocarcinomas in the testes of several inbred strains of mice indicates they originated from embryonic germ cells. The work establishes embryonal carcinoma (EC) cells as a kind of stem cell
• 1968 Edwards and Bavister fertilize the first human egg in vitro
• 1970's EC cells injected into mouse blastocysts produce chimeric mice. Cultured SC cells are explored as models of embryonic development, although their complement of chromosomes is abnormal
• 1978 Louise Brown, the first IVF baby, is born in England
• 1980 Australia's first IVF baby, Candace Reed, is born in Melbourne
• 1981 Evans and Kaufman, and Martin derive mouse embryonic stem (ES) cells from the inner cell mass of blastocysts. They establish culture conditions for growing pluripotent mouse ES cells in vitro. The ES cells yield cell lines with normal, diploid karyotyes and generate derivatives of all three primary germ layers as well as primordial germ cells. Injecting the ES cells into mice induces the formation of teratomas. The first IVF baby, Elizabeth Carr, is born in the United States.
• 1984–88 Andrews et al., develop pluripotent, genetically identical (clonal) cells called embryonal carcinoma (EC) cells from Tera-2, a cell line of human testicular teratocarcinoma. Cloned human teratoma cells exposed to retinoic acid differentiate into neuron-like cells and other cell types
• 1989 Pera et al., derive a clonal line of human embryonal carcinoma cells, which yields tissues from all three primary germ layers. The cells are aneuploid (fewer or greater than the normal number of chromosomes in the cell) and their potential to differentiate spontaneously in vitro is typically limited. The behavior of human EC cell clones differs from that of mouse ES or EC cells
• 1994 Human blastocysts created for reproductive purposes using IVF and donated by patients for research, are generated from the 2-pronuclear stage. The inner cell mass of the blastocyst is maintained in culture and generates aggregates with trophoblast-like cells at the periphery and ES-like cells in the center. The cells retain a complete set of chromosomes (normal karyotype); most cultures retain a stem cell-like morphology, although some inner cell mass clumps differentiate into fibroblasts. The cultures are maintained for two passages
• 1995–96 Non-human primate ES cells are derived and maintained in vitro, first from the inner cell mass of rhesus monkeys, and then from marmosets. The primate ES cells are diploid and have normal karyotypes. They are pluripotent and differentiate into cells types derived from all three primary germ layers. The primate ES cells resemble human EC cells and indicate that it should be possible to derive and maintain human ES cells in vitro.
• 1998 Thomson et al., derive human ES cells from the inner cell mass of normal human blastocysts donated by couples undergoing treatment for infertility. The cells are cultured through many passages, retain their normal karyotypes, maintain high levels of telomerase activity, and express a panel of markers typical of human EC cells non-human primate ES cells. Several (non-clonal) cell lines are established that form teratomas when injected into immune-deficient mice. The teratomas include cell types derived from all three primary germ layers, demonstrating the pluripotency of human ES cells. Gearhart and colleagues derive human embryonic germ (EG) cells from the gonadal ridge and mesenchyma of 5- to 9-week fetal tissue that resulted from elective abortions. They grow EG cells in vitro for approximately 20 passages, and the cells maintain normal karyotypes. The cells spontaneously form aggregates that differentiate spontaneously, and ultimately contain derivatives of all three primary germ layers. Other indications of their pluripotency include the expression of a panel of markers typical of mouse ES and EG cells. The EG cells do not form teratomas when injected into immune-deficient mice
• 2000 Scientists in Singapore and Australia led by Pera, Trounson, and Bongso derive human ES cells from the inner cell mass of blastocysts donated by couples undergoing treatment for infertility. The ES cells proliferate for extended periods in vitro, maintain normal karyotypes, differentiate spontaneously into somatic cell lineages derived from all three primary germ layers, and form teratomas when injected into immune-deficient mice.
• 2001 As human ES cell lines are shared and new lines are derived, more research groups report methods to direct the differentiation of the cells in vitro. Many of the methods are aimed at generating human tissues for transplantation purposes, including pancreatic islet cells, neurons that release dopamine, and cardiac muscle cells.

Modified from NIH - Stem Cells: Scientific Progress and Future Research Directions 2001

Cord Blood Stem Cells

• Blood collected from the placental umbilical cord of a newborn baby shortly after birth
  • total amount of blood about 90 ml
• blood stem cells that can be used to generate red blood cells and cells of the immune system
• collected, typed, stored in Cord Blood Bank
  • Both public and private Banks have arisen
  • available for use by the donor and compatible siblings

• suggested use to treat a range of blood disorders and immune system conditions such as leukaemia, anaemia and autoimmune diseases
• cells provide a resource for bone marrow replacement therapy in many diseases

Cord Blood - Disease Treatments

• Acute Lymphoblastic Leukaemia
• Acute Myeloblastic Leukaemia
• Adrenoleukodystrophy
• Blackfan-Diamond
• Chronic Myeloid Leukaemia
• Chronic Lymphocytic leukaemia
• Fanconi's Anaemia
• Hurler's Syndrome
• Krabbe's disease
• Lymphomas
• Myelodysplastic Syndrome
• Mucolipopolysaccharide deficiency
• Osteopetrosis
• Syndrome Severe Aplastic Anaemia
• Severe Combined Immunodeficiency Disease
• Thalassaemia
• Wiskott-Aldrich Syndrome
• Miscellaneous
• Cancer
• Genetic disorders
• Immune deficiency
• Storage disorders

Adult Stem Cells

NIH - What are adult stem cells?

Stem Cells in the Adult

• Connective Tissue
• Bone marrow
  • Blood Cells, Osteoclasts, blasts
• Epithelia
  • Gut
  • Skin
• Neural?

Epidermis: Immortal Stem Cell

Induced Pluripotent Cells

• non-pluripotent cells engineered to become pluripotent
  • a cell with a specialized function ‘reprogrammed’ to an unspecialized state

Stem Cell Markers

In order to carry out research on stem cells, it is important to be able to identify them. A number of different research groups in the late 90's generated several antibodies which specifically identified undifferentiated, differentiating or differentiated stem cells from a number of different sources and species. Note that the nomenclature in some cases is based upon the antibody used to identify the cell surface marker.

• Every cell surface has specialized proteins (receptors) that can selectively bind or adhere to other “signalling” molecules (ligands)
• Different types of receptors differ in structure and affinity for signalling molecules
• Cells use these receptors and molecules that bind to them as a way of communicating with other cells and to carry out their proper functions in the body

• Stage-Specific Embryonic Antigen-1 (SSEA-1) cell surface embryonic antigen which has a role in cell adhesion, migration and differentiation and is often differentially expressed during development. Can be identified by Davor Solter monoclonal antibody MC-480 (SSEA-1).
• Stage-Specific Embryonic Antigen-4 (SSEA-4) cell surface embryonic antigen of human teratocarcinoma stem cells (EC), human embryonic germ cells (EG) and human embryonic stem cells (ES) which is down-regulated following differentiation of human EC cells. Antigen not expressed on undifferentiated murine EC, ES and EG cells but upregulated on differentiation of murine EC and ES cells. Can be identified by Davor Solter monoclonal antibody MC-813-70 (SSEA-4)
• Tumor Rejection Antigen (TRA-1-60) Sialylated Keratan Sulfate Proteoglycan expressed on the surface of human teratocarcinoma stem cells (EC), human embryonic germ cells (EG) and human embryonic stem cells (ES).
• Tumor Rejection Antigen (TRA-1-81) antigen expressed on the surface of human teratocarcinoma stem cells (EC), human embryonic germ cells (EG) and human embryonic stem cells (ES).
  • Both TRA antibodies identify a major polypeptide (Mr 240 kDa) and a minor polypeptide (Mr 415 kDa).
• Oct-4 (Pou5f1 – Mouse Genome Informatics) gene has an essential role in control of developmental pluripotency (Oct4 knockout embryo blastocysts die at the time of implantation). Oct4 also has a role in maintaining viability of mammalian germline.
• Stem Cell Antigen 1 (Sca-1) member of the Ly-6 family of GPI-linked surface proteins (Mr 18 kDa) and a major phenotypic marker for mouse hematopoietic progenitor/stem cell subset.
• CD133, AC133, prominin 5 transmembrane glycoprotein (865 aa) expressed on stem cells with hematopoietic and nonhematopoietic differentiation potential.

• Alkaline Phosphatase
  • embryonic stem cell is characterized by high level of expression alkaline phosphatase (undifferentiated state) ATCC ELF Phosphatase Detection Kit for Embryonic Stem Cells
  • assay to determine if embryonic stem cells are undifferentiated or are starting to differentiate
  • uses a fluorescent detection of endogenous phosphatase activity in embryonic stem cells

PNAS - Expression of molecular markers characteristic of ES cells in morula-derived cell lines

Stem Differentiation

Epithelium

• each generation at least 1 "immortal" stem cell
  • descendants present in patch in future
• Other basal cells
  • leave basal layer and differentiate
• Committed, born different

or may be stem cells equivalent to immortal stem cell in character mortal in sense that their progeny jostled out of basal layer and shed from skin

Amplifying Cells

• Stem cells in many tissues divide only rarely
• give rise to transit amplifying cells
• daughters committed to differentiation that go through a limited series of more rapid divisions before completing the process.
• each stem cell division gives rise in this way to eight terminally differentiated progeny

Stem Cell Production - Stem Cell Daughter Fates

• Environmental asymmetry
  • daughters are initially similar
  • different pathways according to environmental influences that act on them after they are born
  • number of stem cells can be increased or reduced to fit niche available
• Divisional asymmetry
  • stem cell has an internal asymmetry
  • divides in such a way two daughters are already have different determinants at time of their birth

Current stem cell research

File:NIH stem cell cartoon.jpg

NIH - stem cell cartoon

How to:

• Isolate
• Grow
• Maintain, store
• Differentiate
• Therapeutic uses

Growth of Embryonic Stem Cells

• Mouse blastocyst-derived ES cell line D3
  • from American Type Culture Collection (ATCC)
• Undifferentiated ES cells
  • maintained on gelatin-coated dishes
  • earlier studies, feeder layer

Growth Media

• DMEM (dulbecco’s modified essential media)
• 2 mM glutamine (essential amino acid)
• 0.001% beta-mercaptoethanol (reducing agent)
• 1x nonessential amino acids (amino acids for growth)
• 10% donor horse serum (source of growth factors etc)
• human recombinant leukemia inhibitory factor (LIF) 2,000 units/ml

Neural Therapeutic Uses?

File:Stem cell therapy cartoon.jpg

Stem cell therapy cartoon

NIH - Use of Genetically Modified Stem Cells in Experimental Gene Therapies

Embryonic stem cells develop into functional dopaminergic neurons after transplantation in a Parkinson rat model

• Implantation of fetal dopamine (DA) neurons can reduce parkinsonism in patients
• current methods are rudimentary
• lacking a reliable donor cell source

Transplanted ES cells can develop spontaneously into dopamine (DA) neurons

• Such DA neurons can restore cerebral function and behavior in an animal model of Parkinson's disease
• Björklund et al Proc. Natl. Acad. Sci. USA, Vol. 99, Issue 4, 2344-2349, February 19, 2002

Parkinson Rat Model

Embryonic stem cell Transplant

• transplanting low doses of undifferentiated mouse embryonic stem (ES) cells into rat striatum
• results in a proliferation of ES cells into fully differentiated DA neurons
• ES cell-derived DA neurons caused gradual and sustained behavioral restoration of DA-mediated motor asymmetry

Staining of a Graft

• 16 weeks after implantation of D3 ES cells into adult 6-OHDA lesioned striatum
  • TH-positive neurons were found within the graft (A and B, green)
  • All TH-positive profiles coexpressed the neuronal marker NeuN (A, red)
  • TH (B) also was coexpressed with DAT (C, red) and AADC (D, blue), shown by white triple labelling (E)

Rotation response to Amphetamine

• 6-OHDA-lesioned animals were selected for transplantation by quantification of rotational behaviour in response to amphetamine
• response was examined post-transplantation at 5, 7, and 9 weeks
• Animals with ES cell-derived DA neurons showed recovery over time from amphetamine-induced turning behavior

References

Textbooks

Essential Cell Biology

• Chapter 19 Tissues p622-627

Molecular Biology of the Cell

Alberts, Bruce; Johnson, Alexander; Lewis, Julian; Raff, Martin; Roberts, Keith; Walter, Peter New York and London: Garland Science; c2002

• Molecular Biology of the Cell 4th ed. - Chapter 19 Cellular Mechanisms of Development p1037-1039

• Figure 22-4. The definition of a stem cell
• Figure 22-19. Renewal of the gut lining
• Figure 22-5. Two ways for a stem cell to produce daughters with different fates

Molecular Cell Biology

Lodish, Harvey; Berk, Arnold; Zipursky, S. Lawrence; Matsudaira, Paul; Baltimore, David; Darnell, James E. New York: W. H. Freeman & Co.; c1999

• Molecular Cell Biology - Chapter 23. Cell Interactions in Development
• Figure 24-8. Formation of differentiated blood cells from hematopoietic stem cells in the bone marrow

The Cell- A Molecular Approach

Cooper, Geoffrey M. Sunderland (MA): Sinauer Associates, Inc.; c2000

• The Cell - A Molecular Approach - IV. Cell Regulation Chapter 14. Cell Proliferation in Development and Differentiation
• Stem Cells

Search Online Textbooks

• "stem cell" Molecular Biology of the Cell | Molecular Cell Biology | The Cell- A molecular Approach

PubMed

Reviews

• Jensen J, Hyllner J, Björquist P. Human embryonic stem cell technologies and drug discovery. J Cell Physiol. 2009 Jun;219(3):513-9. Review. PMID: 19277978

Articles

• Allen ND, Baird DM. Telomere length maintenance in stem cell populations. Biochim Biophys Acta. 2009 Feb 11. [Epub ahead of print] PMID: 19419691
• Kenji Matsumoto, Takayuki Isagawa, Toshinobu Nishimura, Takunori Ogaeri, Koji Eto, Satsuki Miyazaki, Jun-ichi Miyazaki, Hiroyuki Aburatani, Hiromitsu Nakauchi, and Hideo Ema Stepwise Development of Hematopoietic Stem Cells from Embryonic Stem Cells PLoS ONE. 2009; 4(3): e4820. Published online 2009 March 16. doi: 10.1371/journal.pone.0004820. PMCID: PMC2653650
• Tesar PJ. Derivation of germ-line-competent embryonic stem cell lines from preblastocyst mouse embryos. Proc Natl Acad Sci U S A. 2005 Jun 7;102(23):8239-44. Epub 2005 May 25. PMID: 15917331

Search Entrez

• stem cell
• stem cell marker
• embryonic stem cell
• mesenchymal stem cell

Links

• UNSW Embryology Stem Cells
• Australian Stem Cell Centre Australian Stem Cell Centre | Public Education | Fact Sheets | Australasian Society for Stem Cell Research
• NIH Stem Cell Information Home Page | Stem Cell Bank (NSCB) | Stem Cells: Scientific Progress and Future Research Directions 2001 | Regenerative Medicine 2006
• International Consortium of Stem Cell Networks International Consortium of Stem Cell Networks | Stem Cell Legislation - World Map | FAQs
• STEM CELLS Journal Stem Cells Portal