Science Current Events | Science News | Brightsurf.com
 
Email a Friend Send to a friend
Printer Friendly Print Testes stem cell can change into other body tissues, Stanford/UCSF study shows
Slashdot It! Slashdot Testes stem cell can change into other body tissues, Stanford/UCSF study shows
Submit to Reddit Submit Testes stem cell can change into other body tissues, Stanford/UCSF study shows to Reddit
Reading: Testes stem cell can change into other body tissues, Stanford/UCSF study showsTwitter This Reading: Testes stem cell can change into other body tissues, Stanford/UCSF study showsTwitter Testes stem cell can change into other body tissues, Stanford/UCSF study shows
Add to Facebook Add Testes stem cell can change into other body tissues, Stanford/UCSF study shows to Facebook

Testes stem cell can change into other body tissues, Stanford/UCSF study shows

January 06, 2009

STANFORD, Calif. - Scientists at the Stanford University School of Medicine and at UC-San Francisco have succeeded in isolating stem cells from human testes. The cells bear a striking resemblance to embryonic stem cells - they can differentiate into each of the three main types of tissues of the body - but the researchers caution against viewing them as one and the same.

According to the study, the testes stem cells have different patterns of gene expression and regulation and they do not proliferate and differentiate as aggressively as human embryonic stem cells.




The findings, published in the January issue of the journal Stem Cells, are in contrast to those reported in a recent Nature paper, which concluded that the cells were, in fact, as pluripotent as embryonic stem cells. Pluripotent cells can become any cell in the body and form tumors called teratomas when transplanted into mice.

"It's time to reinterpret the data," said Renee Reijo-Pera, PhD, professor of obstetrics & gynecology at Stanford, "and to accept that we're beginning to discover many different types of stem cells. Although they are all related to each other, they also all have unique therapeutic applications in which they surpass other family members."

Reijo-Pera, who is the director of Stanford's Center for Human Embryonic Stem Cell Research and Education, collaborated with male infertility specialist Paul Turek, MD, a professor of urology at UCSF and the director of The Turek Clinic in San Francisco, to conduct the research. Reijo-Pera and Turek are co-senior authors of the study.

The stem cells from the testes seem to hover in a gray area between true pluripotency and the more limited, tissue-specific multipotency exhibited by many types of adult stem cells. They termed the cells "multipotent germline stem cells." Germ cells are those cells in the body that differentiate to make sperm and eggs.

Playing to these cells' strengths - in this case, their likely ability to differentiate into cells involved in male reproduction - may be a wiser choice than trying to pigeonhole them as embryonic-stem-cell-wannabes, said Reijo-Pera.

"These cells could potentially treat infertility or other diseases in men," Turek said.

But the lure of pluripotency is strong. An easily accessible source of unmodified, pluripotent human cells would allow physicians and researchers to create cell lines and tissues identical to others in the donor's body. Theoretically such cells could be used as a perfectly matched therapy for that particular donor - perhaps to generate new cartilage to repair a knee injury or new neurons to treat nerve damage. Alternatively, the technique could be used to derive cell lines carrying specific disease-causing mutations - from a man with Parkinson's, for example-on which to conduct research.

Coaxing specialized, or differentiated, adult cells to regress back into a more malleable, embryonic-stem-cell-like state (a process called "induced pluripotency") would also allow scientists to realize the therapeutic benefits of embryonic cells without the thorny ethical problems that plague cells derived from embryos. Until recently, however, the reprogramming of differentiated cells required the use of viruses to introduce specific genes into the cells, which may limit their therapeutic usefulness.

The researchers used cells obtained via biopsies conducted to diagnose male infertility in 19 of the clinic's patients. Each patient's cells were cultured in a manner similar to human embryonic stem cells; two of the 19 samples yielded cell lines with many characteristics of the pluripotent cells. One of the two patients from whom the cell lines were derived withdrew from the study and his samples were discarded.

Further study on the remaining cell line indicated that it expressed many, but not all, genes associated with pluripotency. The cells could also be induced to differentiate into decidedly non-testicular neural cell precursors and they expressed the telomerase enzyme essential to keep pluripotent cells young and unspecialized. However, when the researchers examined the cells' patterns of methylation - a modification to DNA that affects gene expression - they found that the newly derived cell line was less-thoroughly methylated as compared to human embryonic stem cells in one region and more heavily methylated than human embryonic stem cells in another region.

Finally, when the researchers injected the human stem cells into mice with compromised immune systems, they showed only a limited ability to form a teratoma - a kind of tumor formed of many cell types. Teratoma formation resulting from the aggressive proliferation and differentiation of transplanted stem cells is a hallmark of true pluripotency. Together, the results suggest that the stem cells isolated from male testes have some, but not all the characteristics of true pluripotent cells.

"It's not yet possible to completely re-create human embryonic stem cells from germline cells," said Reijo-Pera, "These cells differ in gene expression, methylation and in their ability to form teratomas. But it's the fact that they are different that makes them so interesting. Suggesting otherwise would do a disservice to the research community by overlooking the fact that these cells are a unique cell type that could be really useful in the study of human germ cell formation."

Stanford University Medical Center





Science News and Science Current Events Tag Cloud
This tag cloud is a visual representation of term frequencies of random science news topics with common terms grouped together and emphasized by their display size.
Cardiovascular   Health   Parkinson’s Disease   Ageing   Polio   Parkinson's disease   Liquid Crystal   Type 2 Diabetes   Mangrove   Synthetic Biology   Gallstones   Viscosity   Mussels   Lymph Nodes   Maize   Schizophrenia   Embryonic Development   Academic Performance   Ibuprofen   Oral Cancer   Jellyfish   Bone Marrow   World Trade Center   Drought   Infertility  
Related Embryonic Stem Cells Current Events and Embryonic Stem Cells News Articles Embryonic Stem Cells Current Events and Embryonic Stem Cells News RSS Embryonic Stem Cells Current Events and Embryonic Stem Cells News RSS
Female human embryos adjust the balance of X chromosomes before implantation
Dutch researchers have found the first evidence that a process of inactivating the X chromosome during embryo development and implantation, which was known to occur in mice but unknown in humans, does, in fact, take place in human female embryos prior to implantation in the womb.

June 25, 2009 A Trio of Signals Converge to Induce Liver and Pancreas Cell Development in the Embryo
Understanding the molecular signals that guide early cells in the embryo to develop into different organs provides insight into ways that tissues regenerate and how stem cells can be used for new therapies.

MU scientists convert pigs' connective tissue cells into stem cells
For years, proponents have touted the benefits of embryonic stem cell research, but the potential therapies still face hurdles.

Engineered pig stem cells bridge the mouse-human gap
The discovery that adult skin cells can be 'reprogrammed' to behave like stem cells has been a major scientific boon, providing a way to tap the potential of embryonic stem cells without the associated ethical quandaries.

Stem cell protein offers a new cancer target
A protein abundant in embryonic stem cells is now shown to be important in cancer, and offers a possible new target for drug development, report researchers from the Stem Cell Program at Children's Hospital Boston.

The future of personalized cancer treatment: An entirely new direction for RNAi delivery
In technology that promises to one day allow drug delivery to be tailored to an individual patient and a particular cancer tumor, researchers at the University of California, San Diego School of Medicine, have developed an efficient system for delivering siRNA into primary cells.

Embryo's heartbeat drives blood stem cell formation
Biologists have long wondered why the embryonic heart begins beating so early, before the tissues actually need to be infused with blood.

Bone marrow stem cell co-transplantation prevents embryonic stem cell transplant-associated tumors
Transplanted embryonic stem cells are recognized as a potential treatment for patients suffering from the effects of spinal cord injury (SCI).

Hebrew University researchers neutralize tumor growth in embryonic stem cell therapy
Researchers at the Hebrew University of Jerusalem have discovered a method to potentially eliminate the tumor-risk factor in utilizing human embryonic stem cells.

Scientists shed light on inner workings of human embryonic stem cells
Scientists at UC Santa Barbara have made a significant discovery in understanding the way human embryonic stem cells function.
More Embryonic Stem Cells Current Events and Embryonic Stem Cells News Articles
Embryonic Stem Cells: Methods and Protocols (Methods in Molecular Biology)

Embryonic Stem Cells: Methods and Protocols (Methods in Molecular Biology)
by Kursad Turksen (Editor)

Ottawa Health Research Institute, Canada. Features detailed protocols for establishing and characterizing various lineages using ES cells, reproducible protocols for the cellular and molecular manipulation of differentiating ES cells, techniques for use with ES cells, and tips from experts on avoiding pitfalls. Outline format.

Embryonic Stem Cells: A Practical Approach (Practical Approach Series)

Embryonic Stem Cells: A Practical Approach (Practical Approach Series)
by Elena Notarianni (Editor), Martin J. Evans (Editor)

The groundbreaking isolation of embryonic stem cells (or 'ES cells') of the mouse in the early 1980s triggered a sustained expansion of global research into their exploitation. This led to the routine genetic engineering of the mouse and revolutionised our understanding of biological processes in the context of the whole animal. ES cell biology remains a crucial and growing area of research with far-reaching implications for developmental and comparative biology as well as for human health.
This book serves as a primer to ES cells, their derivation and experimental manipulation. It contains a broad compendium of methods of direct relevance to both graduate students and specialist researchers. An introductory chapter by the principle originator of ES cell research outlines the...

Embryonic Stem Cells (Human Cell Culture)

Embryonic Stem Cells (Human Cell Culture)
by Springer

If you wish to grow or characterize embryonic stem cells or persuade them to differentiate into a particular cell type, then this book contains information that is vital to your success. The aim is to provide clear simple instructions and protocols for growing, maintaining and characterizing embryonic stem cells and details of the various methods used to make stem cells differentiate into specific cell types. The contents will be of interest to stem cell biologists, tissue engineers and scientists wishing to use embryonic stem cells for therapeutic purposes. Each chapter has been written and edited by internationally respected scientists working at the cutting edge of technological developments in human embryonic stem cells.



The Human Embryonic Stem Cell Debate: Science, Ethics, and Public Policy (Basic Bioethics)

The Human Embryonic Stem Cell Debate: Science, Ethics, and Public Policy (Basic Bioethics)
by Suzanne Holland (Editor), Karen Lebacqz (Editor), Laurie Zoloth (Editor)

Human embryonic stem cells can divide indefinitely and have the potential to develop into many types of tissue. Research on these cells is essential to one of the most intriguing medical frontiers, regenerative medicine. It also raises a host of difficult ethical issues and has sparked great public interest and controversy. This book offers a foundation for thinking about the many issues involved in human embryonic stem cell research. It considers questions about the nature of human life, the limits of intervention into human cells and tissues, and the meaning of our corporeal existence. The fact that stem cells may be derived from living embryos that are destroyed in the process or from aborted fetuses ties the discussion of stem cell research to the ongoing debates on abortion. In...

Lines That Divide: The Great Stem Cell Debate

Lines That Divide: The Great Stem Cell Debate
Directed By: Brian Godawa
Also With: Jack Hafer (Producer), Jennifer Lahl (Producer)

With the Obama administration recently announcing its policy change on the issue of stem cell research and regenerative medicine, the questions surrounding this issue are increasingly more complex. This is why Lines That Divide: The Great Stem Cell Debate, a feature length documentary on stem cell research was made. Is stem cell research a potential miracle cure for diseases or a form of biological colonialism? The debate still rages over this controversial science. Supporters argue that it is our moral duty to pursue scientific progress that provides healing hope for humanity. Detractors argue that the ends don't justify the means in harvesting some human life to save others places our nations heart and soul on the same path as Germany in the late 1930's. This documentary seeks to...

Embryonic Stem Cell Protocols: Volume I: Isolation and Characterization (Methods in Molecular Biology)

Embryonic Stem Cell Protocols: Volume I: Isolation and Characterization (Methods in Molecular Biology)
by Kursad Turksen (Editor)

Now in two volumes, this completely updated and expanded edition of Embryonic Stem Cells: Methods and Protocols provides a diverse collection of readily reproducible cellular and molecular protocols for the manipulation of nonhuman embryonic stem cells. Volume one, Embryonic Stem Cell Protocols: Isolation and Characterization, Second Edition, provides a diverse collection of readily reproducible cellular and molecular protocols for the isolation, maintenance, and characterization of embryonic stem cells. The second volume, Embryonic Stem Cell Protocols: Differentiation Models, Second Edition, covers state-of-the-art methods for deriving many types of differentiating cells from ES cells. A companion CD provides electronic color versions of all illustrations in the book. Together, the two...

  Stem Cell Research - Embryonic Versus Adult

Full text of the legislation. An interesting read from the library of congressional archives.

Human Embryonic Stem Cell Protocols (Methods in Molecular Biology)

Human Embryonic Stem Cell Protocols (Methods in Molecular Biology)
by Kursad Turksen (Editor)

A comprehensive collection of diverse techniques for the molecular and cellular manipulation of human embryonic stem (hES) cells. These readily reproducible methods have been optimized for the derivation, characterization, and differentiation of hES cells, with special attention given to regenerative medicine applications. A companion CD provides color versions of all illustrations in the book. The protocols follow the successful Methods in Molecular Biology™ series format, each offering step-by-step laboratory instructions, an introduction outlining the principles behind the technique, lists of the necessary equipment and reagents, and tips on troubleshooting and avoiding known pitfalls.

Human Embryonic Stem Cells, Second Edition

Human Embryonic Stem Cells, Second Edition
by Ann Kiessling (Author), Scott C. Anderson (Author)

The second edition of Kiessling and Anderson's text, Human Embryonic Stem Cells, continues to address the social, legal and ethical debates resulting from the Bush Administrations restriction of federal funding for embryonic stem cell therapy. The emerging field of human embryonic stem cell biomedicine crosses many disciplinary boundaries -- cell biology, reproductive biology, embryology, molecular biology, endocrinology, immunology, fetal medicine, transplantation medicine, and surgery. This single reference provides basic information from these multiple disciplines as it pertains to the science of stem cells.

Embryonic Stem Cell Protocols: Volume I: Isolation and Characterization (Methods in Molecular Biology)

Embryonic Stem Cell Protocols: Volume I: Isolation and Characterization (Methods in Molecular Biology)
by Humana Press

Now in two volumes, this completely updated and expanded edition of Embryonic Stem Cells: Methods and Protocols provides a diverse collection of readily reproducible cellular and molecular protocols for the manipulation of nonhuman embryonic stem cells. Volume one, Embryonic Stem Cell Protocols: Isolation and Characterization, Second Edition, provides a diverse collection of readily reproducible cellular and molecular protocols for the isolation, maintenance, and characterization of embryonic stem cells. The second volume, Embryonic Stem Cell Protocols: Differentiation Models, Second Edition, covers state-of-the-art methods for deriving many types of differentiating cells from ES cells. A companion CD provides electronic color versions of all illustrations in the book. Together, the two...

© 2009 BrightSurf.com