Category Archives: Stem Cells

ScienceDaily (Apr. 24, 2012) Sibling growth factors cooperate to maintain a pool of neuron-generating stem cells in the brain, according to a study published in the journal Stem Cells by researchers at the University of Medicine and Dentistry of New Jersey (UMDNJ).

Numerous soluble proteins and receptors help to maintain neural stem cells' (NSCs) supportive environment in central nervous system (CNS). NSCs access some of these nurturing factors by sending cellular extensions into the cerebral spinal fluid (CSF), which is rich in stem cell-promoting proteins.

Insulin-like growth factors (IGF-I and IGF-II) are essential for the growth and development of the CNS. But although they are abundant in the brain and CSF, it was not clear whether they are required by NSCs. Steven Levison, PhD, and Teresa Wood, PhD, of UMDNJ-New Jersey Medical School and colleagues now show that IGF-I and -II cooperate to maintain NSC numbers and the NSCs' ability to self-renew. IGF-I maintains NSC numbers by promoting cell division (via the IGF-I receptor), whereas IGF-II drives the expression of proteins essential for NSC self-renewal and 'stemness' (via the insulin receptor).

The role of IGF-I and -II in maintaining NSC numbers and function might help to explain the cognitive impairments associated with aging, as the abundance of both proteins declines with age.

This study was funded by a Dean's grant from UMDNJ-New Jersey Medical School, NIH grants (R21HL094905, F31NS065607 and T32-HL069752) and a grant from the LeDucq Foundation.

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The above story is reprinted from materials provided by University of Medicine and Dentistry of New Jersey (UMDNJ), via Newswise.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.

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Division of labor in neural stem cell maintenance

Public release date: 26-Apr-2012 [ | E-mail | Share ]

Contact: Professor Palle Serup palle.serup@sund.ku.dk 01-145-402-20026 University of Copenhagen

Scientists from The Danish Stem Cell Center (DanStem) at the University of Copenhagen and Hagedorn Research Institute have gained new insight into the signaling paths that control the body's insulin production. This is important knowledge with respect to their final goal: the conversion of stem cells into insulin-producing beta cells that can be implanted into patients who need them. The research results have just been published in the well-respected journal PNAS.

Insulin is a hormone produced by beta cells in the pancreas. If these beta cells are defective, the body develops diabetes. Insulin is vital to life and therefore today the people who cannot produce their own in sufficient quantities, or at all, receive carefully measured doses often via several daily injections. Scientists hope that in the not-so-distant future it will be possible to treat diabetes more effectively and prevent secondary diseases such as cardiac disease, blindness and nerve and kidney complications by offering diabetes patients implants of new, well-functioning, stem-cell-based beta cells.

"In order to get stem cells to develop into insulin-producing beta cells, it is necessary to know what signaling mechanisms normally control the creation of beta cells during fetal development. This is what our new research results can contribute," explains Professor Palle Serup from DanStem.

"When we know the signaling paths, we can copy them in test tubes and thus in time convert stem cells to beta cells," says Professor Serup.

The new research results were obtained in a cooperative effort between DanStem, the Danish Hagedorn Research Institute and international partners in Japan, Germany, Korea and the USA. The scientific paper has just been published in the well-respected international journal PNAS (Proceedings of the National Academy of Sciences of the United States of America) entitled Mind bomb 1 is required for pancreatic -cell formation.

Better control of stem cells

The signaling mechanism that controls the first steps of the development from stem cells to beta cells has long been known.

"Our research contributes knowledge about the next step in development and the signaling involved in the communication between cells an area that has not been extensively described. This new knowledge about the ability of the so-called Notch signaling first to inhibit and then to stimulate the creation of hormone-producing cells is crucially important to being able to control stem cells better when working with them in test tubes," explains Professor Palle Serup .

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Stem cell researchers map new knowledge about insulin production

Mike Ivey writes on all matters money in the spirit of Capital Times founder William T. Evjue, who believed that the concentration of wealth in the U.S. is not healthy for the Democracy.

When UW-Madison's James Thomson in 1998 became the first scientist to grow human embryonic stem cells in a lab, it generated tremendous excitement about the medical possibilities.

Thomson tried to downplay the breakthrough but talk spread about cures for Alzheimers or Parkinsons disease, growing livers for cirrhosis suffers or producing healthy heart cells for cardiac patients.

The miracle cures have been slow in coming, however. Scientists can replicate healthy nerve cells in a Petri dish but havent found a way to replace defective spinal cells in ALS victims, for example.

In many ways, were still at the first steps,Anita Bhattacharyya, a senior scientist in the stem cell program at the UW's Waisman Center, told a business group Tuesday.

Butproducing stem cells for others to use is proving one of Madisons more promising new business ventures. Pharmaceutical companies in particular are using stem cells to test drugs before launching into expensive further testing.

Were making these cells available to the masses, says Chris Parker, chief technology officer at Cellular Dynamics International.

Launched by Thomson -- and backed with $100 million from a local investor group -- Cellular Dynamics International was lauded recently by MIT as one of the 50 most important companies in the world

Since its founding in 2005, the company now counts 107 employees at it offices in University Research Park and is continuing to grow.

Im hiring right now, Parker joked toa lunch crowd of the Wisconsin Technology Council Tuesday.

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Biz Beat: Making stem cells "available to the masses"

April 21, 2012

Researchers have discovered a new stem cell in the adult brain a discovery which could lead to new treatments for strokes and neurodegenerative conditions.

The discovery was made by researchers at Lund University in Sweden, who found the stem cells located around small blood vessels in the brain while analyzing brain tissues obtained from biopsies.

These cells can proliferate and form several different cell types, including new brain cells, and while their exact function is unclear at this point, experts hope they can lead to the discovery of new methods in order to heal and repair diseases and injuries of the brain.

A similar cell type has been identified in several other organs where it can promote regeneration of muscle, bone, cartilage and adipose tissue, Dr, Patrik Brundin, senior author of the study, Head of the Neuronal Survival Unit at Lund University, and Jay Van Andel Endowed Chair in Parkinsons Research at Van Andel Institute (VAI), said in a press release on Thursday.

According to Sue Thoms of MLive.com, stem cells have been proven capable of healing and repairing injuries in other organs, and if Brundin and his colleagues hope to achieve similar results with the stem cells found in the brain, they will first have to try to control and enhance the cells self-healing properties. The goal, they say, will be to carry out therapies targeted to a specific location within the brain itself.

Our findings show that the cell capacity is much larger than we originally thought, and that these cells are very versatile, said Dr. Gesine Paul-Visse, primary author of the study, which has been published in the journal PLoS ONE, and an associate professor of neuroscience at Lund University.

Most interesting is their ability to form neuronal cells, but they can also be developed for other cell types. The results contribute to better understanding of how brain cell plasticity works and opens up new opportunities to exploit these very features, Paul-Visse added. We hope that our findings may lead to a new and better understanding of the brains own repair mechanisms. Ultimately the goal is to strengthen these mechanisms and develop new treatments that can repair the diseased brain.

Source: RedOrbit Staff & Wire Reports

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New Stem Cell Discovered In The Brain

When pitching in the Dominican Republic, C.J. Nitkowski said he felt he was back to his normal self on the mound

STORY HIGHLIGHTS

For the full story on C.J. Nitkowski's risky medical procedure and baseball comeback, watch CNN Presents, Sunday night at 8ET.

Alpharetta, Georgia (CNN) -- At 39 years old, Christopher John Nitkowski really has no business trying to pitch in the major leagues. In the harsh reality of professional sports, he's a has-been.

Just don't tell him that.

The former first-round draft pick last pitched for the Washington Nationals in 2005 after a 10-season career spent mostly as a left-handed reliever.

"You go as long as you can," he told CNN. "I had a good friend tell me, 'Man, just make them tear the uniform off of you. You can do whatever you're gonna do for the rest of your life. You can't play baseball forever.'"

A doctor injects C.J. Nitkowski's stem cells into his injured shoulder

In the middle of the 2011 baseball season Nitkowski announced in a first-person article for Sports Illustrated that he would try a comeback. After his brief major league appearance in 2005, he pitched subsequent years for one team in Japan and three in South Korea.

This time, he wrote, he would agree to a risky medical experiment that would involve injecting his own stem cells into his injured pitching shoulder, which he hurt in an initial comeback attempt last spring.

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Pitcher hopes stem cell procedure will get him one last season

Despite decades of cancer research, cancer remains a leading cause of death worldwide, accounting for 7.6 million deaths in 2008, and breast cancer is one of the most common causes of cancer deaths each year . In Singapore, more than 1,400 women are diagnosed with breast cancer and more than 300 die as a result of breast cancer each year . The high fatality rate of cancer is partially attributed to the invasive ability of malignant tumors to spread throughout the human body, and the ineffectiveness of conventional therapies to eradicate the cancer cells.

A team of researchers led by IBN Group Leader, Dr Shu Wang, has made a landmark discovery that neural stem cells (NSCs) derived from human induced pluripotent stem (iPS) cells could be used to treat breast cancer. The effectiveness of using NSCs, which originate from the central nervous system, to treat brain tumors has been investigated in previous studies. This is the first study that demonstrates that iPS cell-derived NSCs could also target tumors outside the central nervous system, to treat both primary and secondary tumors.

To test the efficiency of NSCs in targeting and treating breast cancer, the researchers injected NSCs loaded with a suicide gene (herpes simplex virus thymidine) into mice bearing breast tumors. They did this using baculoviral vectors or gene carriers engineered from an insect virus (baculovirus), which does not replicate in human cells, making the carriers less harmful for clinical use. A prodrug (ganciclovir), which would activate the suicide gene to kill the cancerous cells upon contact, was subsequently injected into the mice. A dual-colored whole body imaging technology was then used to track the distribution and migration of the iPS-NSCs.

The imaging results revealed that the iPS-NSCs homed in on the breast tumors in the mice, and also accumulated in various organs infiltrated by the cancer cells such as the lung, stomach and bone. The survival of the tumor-bearing mice was prolonged from 34 days to 39 days. This data supports and explains how engineered iPS-NSCs are able to effectively seek out and inhibit tumor growth and proliferation.

Dr Shu Wang shared, "We have demonstrated that tumor-targeting neural stem cells may be derived from human iPS cells, and that these cells may be used in combination with a therapeutic gene to cripple tumor growth. This is a significant finding for stem cell-based cancer therapy, and we will continue to improve and optimize our neural stem cell system by preventing any unwanted activation of the therapeutic gene in non-tumor regions and minimizing possible side effects."

"IBN's expertise in generating human stem cells from iPS cells and our novel use of insect virus carriers for gene delivery have paved the way for the development of innovative stem cell-based therapies. With their two-pronged attack on tumors using genetically engineered neural stem cells, our researchers have discovered a promising alternative to conventional cancer treatment," added Professor Jackie. Y. Ying, IBN Executive Director.

Compared to collecting and expanding primary cells from individual patients, IBN's approach of using iPS cells to derive NSCs is less laborious and suitable for large-scale manufacture of uniform batches of cellular products for repeated patient treatments. Importantly, this approach will help eliminate variability in the quality of the cellular products, thus facilitating reliable comparative analysis of clinical outcomes.

Additionally, these iPS cell-derived NSCs are derived from adult cells, which bypass the sensitive ethical issue surrounding the use of human embryos, and since iPS cells are developed from a patient's own cells, the likelihood of immune rejection would be reduced.

References: 1. J. Yang, D. H. Lam, S. S. Goh, E. X. L. Lee, Y. Zhao, F. Chang Tay, C. Chen, S. Du, G. Balasundaram, M. Shahbazi, C. K. Tham, W. H. Ng, H. C. Toh and S. Wang, "Tumor Tropism of Intravenously Injected Human Induced Pluripotent Stem Cell-derived Neural Stem Cells and their Gene Therapy Application in a Metastatic Breast Cancer Model," Stem Cells, (2012) DOI: 10.1002/stem.1051.

2. E. X. Lee, D. H. Lam, C. Wu, J. Yang, C. K. Tham and S. Wang, "Glioma Gene Therapy Using Induced Pluripotent Stem Cell-Derived Neural Stem Cells," Molecular Pharmaceutics, 8 (2011) 1515-1524.

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IBN Discovers Human Neural Stem Cells with Tumor Targeting Ability - A Promising Discovery for Breast Cancer Therapy