Author Archives: admin


2014 World Stem Cell Summit presented by GPI, Mary Ann Liebert, Inc, and GEN

PUBLIC RELEASE DATE:

25-Jun-2014

Contact: Vicki Cohn vcohn@liebertpub.com 914-740-2100 x2156 Mary Ann Liebert, Inc./Genetic Engineering News

New Rochelle, NY, June 25, 2014Mary Ann Liebert, Inc., publishers website and Genetic Engineering & Biotechnology News (GEN) are proud to announce that they will again serve as joint platinum media sponsors of the Genetics Policy Institute 2014 World Stem Cell Summit that will take place at the Marriott River Center, December 4-6, 2014 in San Antonio, Texas.

In a new collaborative effort in 2014, Mary Ann Liebert, Inc. will also organize a World Stem Cell Summit panel, comprised of leading editors from their peer-reviewed journals intersecting the field to predict the most innovative translational research that will impact regenerative medicine in the next five years.

Mary Ann Liebert, Inc. will also publish the 2014 World Stem Cell Report as a special supplement to the peer-reviewed journal Stem Cells and Development. Dr. Graham Parker, Editor-in-Chief of Stem Cells and Development, and Bernard Siegel, Executive Director of Genetics Policy Institute (GPI), will serve as Co-Editors-in-Chief of the Report, joined by Rosario Isasi (McGill University) as Managing Editor. The World Stem Cell Report will be made available to all subscribers of Stem Cells and Development and attendees of the World Stem Cell Summit. It will also be available free online in 106 developing countries, courtesy of the Publisher, to facilitate global stem cell research.

"We are very pleased to expand our collaboration with Mary Ann Liebert, Inc., and GEN," says Bernard Siegel, Founder and Co-chair of the Summit. "The commitment by those prestigious publishers to journalistic integrity and scientific knowledge and education matches our enthusiasm to advance the field of stem cells and regenerative medicine for the betterment of humanity. We look forward to working with Graham Parker and the skilled editorial team at Stem Cells and Development to publish our annual Report. We are especially excited to have the expertise of the Liebert editors engaged on the program at the World Stem Cell Summit."

"The World Stem Cell Summit is unequivocally a paramount meeting that brings together the leaders in the field from academia, industry, and business, thereby ensuring the advancement of collaborative opportunities," says Mary Ann Liebert, publisher & CEO of both Stem Cells and Development and GEN. "Bernie Siegel and GPI also recognize the importance of public advocacy at this most important international conference. Mary Ann Liebert, Inc. is delighted to expand our own collaboration with Bernie Siegel and GPI and to publish the 2014 Report.

GEN Editor-in-Chief John Sterling stated, "The World Stem Cell Summit is the critical global meeting, providing the best opportunity for the GEN community to participate in the world of regenerative medicine. Our platinum media sponsorship allows GEN readers and advertisers to have a front row seat to listen and learn from the top experts on the very dynamic and expertly conceptualized Summit platform."

The Summit program delivers on the "big picture," featuring over 200 prominent scientists, business leaders, regulators, policy-makers, advocates, economic development officers, experts in law and ethics, and visionary gurus who will discuss the latest scientific discoveries, business models, legal and regulatory solutions, and best practices. The Summit is expected to attract attendees from more than 40 nations.

Link:
2014 World Stem Cell Summit presented by GPI, Mary Ann Liebert, Inc, and GEN

Thermo Fisher Showcases New Product Innovations and Best Practices to Optimize Stem Cell Discoveries at ISSCR 2014

VANCOUVER, British Columbia--(BUSINESS WIRE)--The latest advances in innovative technologies designed to streamline the entire stem cell research workflow from pluripotent cell engineering, culturing, differentiation and characterization to cryopreservation and storage will be showcased this week during the 12thannual International Society for Stem Cell Research (ISSCR) meeting (Thermo Scientific booth #628, Life Technologies booth #829).

Thermo Fisher Scientific will host a series of customer and thought leader presentations on topics ranging from the use of Sendai virus reprogramming technology for rapid development of human induced pluripotent stem cells (iPSC) for drug development applications, to industrializing pluripotent stem cells and novel platforms for culturing cells in suspension. The speakers will share new innovations being applied in labs at Harvard University, Cedar-Sinai Medical Center and Saitama Medical University.

Access to leading-edge tools that are designed to seamlessly work in combination with each other is critical for our customers to drive new discoveries, said Chris Armstrong, Ph.D., vice president and general manager, cell biology, for Thermo Fisher. Were proud to offer a deep portfolio of technologies that addresses the entire pluripotent stem cell research continuum to enable novel applications in drug discovery and human disease studies.

New product innovations at ISSCR this year include:

Thought Leader Presentations Join fellow ISSCR attendees for sponsored presentations, including: Wednesday, June 18, from 8:30 a.m. 12:30 p.m. (West Ballroom C/D): Conquering Roadblocks Associated with Stem Cell Differentiation and Disease Modeling:

Thursday, June 19, from 11:30 a.m. 12:30 p.m. (West Meeting Room) ISSCR Innovation Showcase

For more information on all Thermo Fisher activities during ISSCR, please visit Thermo Scientific ISSCR 2014 and Life Technologies ISSCR 2014.

About Thermo Fisher Scientific

Thermo Fisher Scientific Inc. is the world leader in serving science, with revenues of $17 billion and 50,000 employees in 50 countries. Our mission is to enable our customers to make the world healthier, cleaner and safer. We help our customers accelerate life sciences research, solve complex analytical challenges, improve patient diagnostics and increase laboratory productivity. Through our four premier brands Thermo Scientific, Life Technologies, Fisher Scientific and Unity Lab Services we offer an unmatched combination of innovative technologies, purchasing convenience and comprehensive support. For more information, please visitwww.thermofisher.com.

Read the original post:
Thermo Fisher Showcases New Product Innovations and Best Practices to Optimize Stem Cell Discoveries at ISSCR 2014

Health minister 'perplexed' by Stamina order

Court in Catania tells Brescia hospital to perform treatment

(ANSA) - Brescia, June 24 - Italian Health Minister Beatrice Lorenzin said she was "perplexed" Tuesday after a court in Catania ordered hospital authorities in Brescia to administer the controversial Stamina stem-cell treatment. The Catania order followed earlier orders from courts in Pesaro and Venice for the Brescia hospital to administer the treatment, which has been largely discredited and according to some investigations, actually harmful. Lorenzin said that such court orders undermine Italy's image internationally. "I am perplexed by what is happening, it is bizarre and undermines the image of Italy," as a nation that follows science-based treatments. She said strong action from government and parliament will be needed "for the protection of patients and their families". The Brescia Civic Hospital said Tuesday that it had started to search for doctors and nurses willing to administer the treatment as ordered by the Catania court. Stamina's credibility has long been suspect, and last fall the health ministry ruled that the Stamina Foundation would no longer be allowed to test the treatment on humans. The foundation was also stripped of its non-profit status after a study found its treatment was "ignorant of stem-cell biology". Recent investigations have shown risks of the treatment range from nausea to cancer, and as many as one-quarter of all patients treated have experienced "adverse effects". The head of the foundation, Davide Vannoni, may face indictment. In April, after study results became known, hospitals in Italy announced they had suspended the stem-cell treatment program. Lorenzin said investigators are raising serious allegations against Stamina and members of the Stamina foundation, and courts should think carefully before overriding that and ordering the treatment. But support from some patients who have used or requested the treatment remains strong. In early June, a court in the central Marche region ruled that toddler Federico Mezzina could receive Stamina treatment for Krabbe disease. The Stamina treatment involves extracting bone-marrow stem cells from a patient, turning them into neurons by exposing them to retinoic acid for two hours, and injecting them back into the patient. Supporters of the therapy thought it could be a cure for fatal degenerative nerve diseases such as spinal muscular atrophy, while detractors said it was devoid of scientific merit. A panel of experts appointed by Italy's health ministry said in January it found the therapy seriously lacking in both premise and practice. Their report cited "serious imperfections and omissions in the Stamina protocol, including conceptual errors and an apparent ignorance of stem-cell biology".

Read the original here:
Health minister 'perplexed' by Stamina order

RIKEN press release: Pushing cells towards a higher pluripotency state

PUBLIC RELEASE DATE:

24-Jun-2014

Contact: Jens Wilkinson jens.wilkinson@riken.jp RIKEN

Stem cells have the unique ability to become any type of cell in the body. Given this, the possibility that they can be cultured and engineered in the laboratory makes them an attractive option for regenerative medicine. However, some conditions that are commonly used for culturing human stem cells have the potential to introduce contaminants, thus rendering the cells unusable for clinical use. These conditions cannot be avoided, however, as they help maintain the pluripotency of the stem cells.

In a study published in Scientific Reports, a group from the RIKEN Center for Life Science Technologies in Japan has gained new insight into the role of CCL2, a chemokine known to be involved in the immune response, in the enhancement of stem cell pluripotency. In the study, the researchers replaced basic fibroblast growth factor (bFGF), a critical component of human stem cell culture, with CCL2 and studied its effect. The work showed that CCL2 used as a replacement for bFGF activated the JAK/STAT pathway, which is known to be involved in the immune response and maintenance of mouse pluripotent stem cells. In addition, the cells cultured with CCL2 demonstrated a higher tendency of colony attachment, high efficiency of cellular differentiation, and hints of X chromosome reactivation in female cells, all markers of pluripotency.

To understand the global effects of CCL2, the researchers compared the transcriptome of stem cells cultured with CCL2 and those with bFGF. They found that stem cells cultured with CCL2 had higher expression of genes related to the hypoxic response, such as HIF2A (EPAS1). The study opens up avenues for further exploring the relationship between cellular stress, such as hypoxia, and the enhancement of pluripotency in cells. Yuki Hasegawa of CLST, who led the study, says, "Among the differentially expressed genes, we found out that the most significantly differentially expressed ones were those related to hypoxic responses, and hypoxia is known to be important in the progression of tumors and the maintenance of pluripotency. These results could potentially contribute to greater consistency of human induced pluripotent stem cells (iPSCs), which are important both for regenerative medicine and for research into diseases processes."

As a way to apply CCL2 towards the culturing of human iPSCs with more consistent quality, the researchers developed dishes coated with CCL2 and LIF protein beads. This allowed stem cells to be cultured in a feeder-free condition, preventing the risk that viruses or other contaminants could be transmitted to the stem cells. While the exact mechanisms of how CCL2 enhances pluripotency has yet to be elucidated, this work highlights the usefulness of CCL2 in stem cell culture.

###

AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.

Link:
RIKEN press release: Pushing cells towards a higher pluripotency state

Stem cell transplantation for severe sclerosis associated with improved long-term survival

PUBLIC RELEASE DATE:

24-Jun-2014

Contact: Jacob M. van Laar j.m.vanlaar@umcutrecht.nl The JAMA Network Journals

Among patients with a severe, life-threatening type of sclerosis, treatment with hematopoietic stem cell transplantation (HSCT), compared to intravenous infusion of the chemotherapeutic drug cyclophosphamide, was associated with an increased treatment-related risk of death in the first year, but better long-term survival, according to a study in the June 25 issue of JAMA.

Systemic sclerosis is an autoimmune connective tissue disease characterized by vasculopathy (a disorder of the blood vessels), low-grade inflammation, and fibrosis (development of excess fibrous connective tissue) in skin and internal organs. Previously, small studies have shown that systemic sclerosis is responsive to treatment with autologous HSCT, although it has been unclear whether HSCT improves survival, according to background information in the article. For this study, autologous HSCT involved a multistep process beginning with infusion of high doses of cyclophosphamide and an antibody against immune cells, followed by reinfusion of the patient's own stem cells that had been previously collected from blood and purified.

Jacob M. van Laar, M.D., Ph.D., of the University Medical Center Utrecht, Utrecht, the Netherlands and Dominique Farge M.D., Ph.D, of the Assistance Publique - Hopitaux de Paris, Paris 7 Diderot University, France, and colleagues randomly assigned 156 patients with early diffuse cutaneous (widespread skin involvement) systemic sclerosis to receive HSCT (n = 79) or cyclophosphamide (n = 77; 12 monthly infusions). The phase 3 clinical trial was conducted in 10 countries at 29 centers; patients were recruited from March 2001 to October 2009 and followed up until October 2013.

During a median follow-up of 5.8 years, 53 adverse events occurred: 22 in the HSCT group (19 deaths and 3 irreversible organ failures) and 31 in the control group (23 deaths and 8 irreversible organ failures). Patients treated with HSCT experienced more adverse events (including death) in the first year but had better long-term event-free survival than those treated with cyclophosphamide.

Patients in the HCST group experienced higher mortality in the first year but had better long-term overall survival than those treated with cyclophosphamide. During year 1 there were 11 deaths (13.9 percent, including 8 treatment-related deaths) in the HSCT group vs 7 (9.1 percent, no treatment-related deaths) in the control group. After year 2 of follow-up, there were 12 deaths (15.2 percent) in the HSCT group vs 13 (16.9 percent) in the control group. After 4 years of follow-up, there were 13 deaths (16.5 percent) in the HSCT group vs 20 (26.0 percent) in the control group.

The authors add that HSCT was also more effective than intravenous cyclophosphamide on measures evaluating skin, functional ability, quality of life, and lung function, consistent with previous studies.

"Among patients with early diffuse cutaneous systemic sclerosis, HSCT was associated with increased treatment-related mortality in the first year after treatment. However, HCST conferred a significant long-term event-free survival benefit," the authors conclude.

More:
Stem cell transplantation for severe sclerosis associated with improved long-term survival

Stem Cell Transplantation For Severe Sclerosis Linked With Improved Long-term Survival

Contact Information

Available for logged-in reporters only

Newswise Among patients with a severe, life-threatening type of sclerosis, treatment with hematopoietic stem cell transplantation (HSCT), compared to intravenous infusion of the chemotherapeutic drug cyclophosphamide, was associated with an increased treatment-related risk of death in the first year, but better long-term survival, according to a study in the June 25 issue of JAMA.

Systemic sclerosis is an autoimmune connective tissue disease characterized by vasculopathy (a disorder of the blood vessels), low-grade inflammation, and fibrosis (development of excess fibrous connective tissue) in skin and internal organs. Previously, small studies have shown that systemic sclerosis is responsive to treatment with autologous HSCT, although it has been unclear whether HSCT improves survival, according to background information in the article. For this study, autologous HSCT involved a multistep process beginning with infusion of high doses of cyclophosphamide and an antibody against immune cells, followed by reinfusion of the patient's own stem cells that had been previously collected from blood and purified.

Jacob M. van Laar, M.D., Ph.D., of the University Medical Center Utrecht, Utrecht, the Netherlands and Dominique Farge M.D., Ph.D, of the Assistance Publique - Hopitaux de Paris, Paris 7 Diderot University, France, and colleagues randomly assigned 156 patients with early diffuse cutaneous (widespread skin involvement) systemic sclerosis to receive HSCT (n = 79) or cyclophosphamide (n = 77; 12 monthly infusions). The phase 3 clinical trial was conducted in 10 countries at 29 centers; patients were recruited from March 2001 to October 2009 and followed up until October 2013.

During a median follow-up of 5.8 years, 53 adverse events occurred: 22 in the HSCT group (19 deaths and 3 irreversible organ failures) and 31 in the control group (23 deaths and 8 irreversible organ failures). Patients treated with HSCT experienced more adverse events (including death) in the first year but had better long-term event-free survival than those treated with cyclophosphamide.

Patients in the HCST group experienced higher mortality in the first year but had better long-term overall survival than those treated with cyclophosphamide. During year 1 there were 11 deaths (13.9 percent, including 8 treatment-related deaths) in the HSCT group vs 7 (9.1 percent, no treatment-related deaths) in the control group. After year 2 of follow-up, there were 12 deaths (15.2 percent) in the HSCT group vs 13 (16.9 percent) in the control group. After 4 years of follow-up, there were 13 deaths (16.5 percent) in the HSCT group vs 20 (26.0 percent) in the control group.

The authors add that HSCT was also more effective than intravenous cyclophosphamide on measures evaluating skin, functional ability, quality of life, and lung function, consistent with previous studies.

Among patients with early diffuse cutaneous systemic sclerosis, HSCT was associated with increased treatment-related mortality in the first year after treatment. However, HCST conferred a significant long-term event-free survival benefit, the authors conclude. (doi:10.1001/jama.2014.6368; Available pre-embargo to the media at http://media.jamanetwork.com)

Editors Note: Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.

Link:
Stem Cell Transplantation For Severe Sclerosis Linked With Improved Long-term Survival

Immediate closure of Arroyo stem cell doctor's clinic ordered

CLOSURE. The Tagaytay City Office of the Mayor orders the immediate closure of the Green & Young Health & Wellness Center. Photo by Jee Geronimo/Rappler

MANILA, Philippines The clinic in Tagaytay City where former President Gloria Macapagal-Arroyo sought alternative treatment in 2012 but whose doctor was recently exposed to be unlicensed has been ordered to close down.

In a resolution dated May 29, the office of Mayor Agnes Tolentino directed Antonia Park to immediately stop the operation of her clinic which was listed as a massage clinic/sauna/turkish/swedish bath.

The resolution listed down adequate, relevant evidence that Park unlawfully used and practiced medicine in her clinic. It cited the following in revoking Green & Young Health & Wellness Center's business permit:

The above evidence were based on several affidavits, a Professional Regulatory Commission document which showed Park is not authorized to practice medicine in the country, and a 2012 statement from Park regarding the condition of and alternative treatment for Arroyo.

In July 2012, Park took in Arroyo for possible stem cell therapy. Park used the title MD in her statement released to the press. (READ: Fourth stem cell treatment for Arroyo)

Republic Act 2382 or The Medical Act of 1959 considers a person as engaged in the practice of medicine when he/she uses MD after his/her name.

ILLEGAL PRACTICE. Dr Antonia Park in this Nov 17, 2012 photo taken by Kate Tan. Photo from Bernard Tan.

Since Park herself admitted she is not a registered physician in the Philippines, any act constituting practice of medicine will be considered as violative of the law.

The Office of the Mayor said in the resolution it found sufficient ground for the revocation of the business permit and the closure of the establishment.

More:
Immediate closure of Arroyo stem cell doctor's clinic ordered

Scientists identify link between stem cell regulation and the development of lung cancer

PUBLIC RELEASE DATE:

19-Jun-2014

Contact: Shaun Mason smason@mednet.ucla.edu 310-206-2805 University of California - Los Angeles

UCLA researchers led by Dr. Brigitte Gomperts have discovered the inner workings of the process thought to be the first stage in the development of lung cancer. Their study explains how factors that regulate the growth of adult stem cells that repair tissue in the lungs can lead to the formation of precancerous lesions.

Findings from the three-year study could eventually lead to new personalized treatments for lung cancer, which is responsible for an estimated 29 percent of U.S. cancer deaths, making it the deadliest form of the disease.

The study was published online on June 19 in the journal Stem Cell. Gomperts, a member of the UCLA Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research and the UCLA Jonsson Comprehensive Cancer Center, collaborated with Manash Paul and Bharti Bisht, postdoctoral scholars and co-lead authors of the study.

Adult stem cells in lung airways are present specifically to repair the airways after injury or disease caused by smoking, pollution, viruses or other factors. Gomperts and her team found that this reparative process is tightly regulated by molecules called reactive oxygen species, or ROS.

Recent research has shown that low levels of ROS are important for signaling the stem cells to perform important functions such as repairing tissue damage while high levels of ROS can cause stem cells to die. But the level of ROS needed for repair to be initiated has remained a subject of debate among researchers.

The UCLA study found that the dynamic flux of ROS from low to moderate levels in the airway stem cells is what drives the repair process, and that the increase in ROS levels in the repairing cell is quickly reduced to low levels to prevent excessive cell proliferation.

Gomperts' lab found that disrupting this normal regulation of ROS back to low levels is equivalent to pulling the brakes off of the stem cells: They will continue to make too many of themselves, which causes the cells not to mature and instead become precancerous lesions. Subsequent progressive genetic changes to the cells in these lesions over time can eventually allow cancerous tumors to form.

Continue reading here:
Scientists identify link between stem cell regulation and the development of lung cancer

The Adult Stem Cell Technology Center, LLC Announces Patent for Induced Pluripotent Stem Cells Produced with a Single …

Valencia, Spain (PRWEB) June 24, 2014

Today at Cell Science-2014 in Valencia, Spain, Dr. James L. Sherley, Director of Bostons Adult Stem Cell Technology Center, LLC, announced the issue of another significant patent to the companys growing portfolio of adult tissue stem cell intellectual property. The new patent issued today (U.S. Patent and Trademark Office No. 8,759,098) protects a method for producing induced pluripotent stem cells (iPSCs) with a single non-genetic agent.

Director Sherley made the announcement at the conclusion of his keynote address at the 4th Annual World Congress on Cell Science and Stem Cell Research. After discussing unique aspects of adult stem cells that are often overlooked, he highlighted a proposed connection between adult stem cells and iPSCs that was the basis for the newly patented biotechnology.

iPSCs are currently the subject of intense biological and biomedical research. These artificially produced stem cells provide the research capabilities of human embryonic stem cells (hESCs). But since their production does not involve human embryos, iPSCs do not pose ethical concerns. However, because of their genetic defects and propensity for forming tumors, also like hESCs, it is unlikely that iPSCs will ever be of sufficient quality and safety for use in regenerative medicine therapies.

Despite the problems preventing direct application of iPSCs for medical therapies, their use to develop biological surrogate cells for difficult-to-obtain cells for diseased human tissues for research is unparalleled (e.g., living brain cells from children with autism). For this reason, new technologies, like those represented by the ASCTCs new patent, are important for leading the way to more efficient production of higher quality iPSCs.

Unlike the recently discredited reports of acidic conditions as a single non-genetic agent for producing iPSCs, the ASCTCs technology has a well-established historical record and biological rationale. The method was originally proposed in the National Institutes of Health (NIH) Directors Pioneer Award research of ASCTC Director Sherley, when he was a research professor at the Massachusetts Institute of Technology.

The active agent, xanthine, is a naturally occurring normal compound found in the bodys blood and tissues. In earlier ASCTC studies, xanthine was shown active for expanding adult tissue stem cells. Xanthine is a member of a class of compounds called purines that regulate the action of a well-known cancer-protective gene called p53. The p53 gene has also been shown by several laboratories to be an important factor in the efficiency of iPSC cell production.

For the ASCTC technology, xanthine-expanded adult tissue stem cells are placed in commonly used iPSC culture medium supplemented with xanthine as the only additive. The usual introduction of specific genes or their experimental manipulation is not required. The new single-agent technology yields iPSCs at efficiencies similar to methods that require direct genetic manipulation.

The ASCTCs iPSC production technology was described in an earlier issue of the Journal of Biomedicine and Biotechnology (Par, J.-F., and Sherley, J. L. 2011. Culture Environment-Induced Pluripotency of SACK-Expanded Tissue Stem Cells, J. Biomed. Biotechnol. vol. 2011, Article ID 312457, 12 pp., 2011. doi:10.1155/2011/312457). Thus far, the method has only been applied to purine-expanded mouse pancreatic tissue stem cells. It also has not been evaluated for combined effects with other iPSC production methods. Director Sherley notes that, wider evaluation of the new technology will help to establish its range as an advantageous new reagent for producing higher quality iPSCs more efficiently.

************************************************************************************************************* The Adult Stem Cell Technology Center, LLC (ASCTC) is a Massachusetts life sciences company established in September 2013. ASCTC director and founder, James L. Sherley, M.D., Ph.D. is the foremost authority on the unique properties of adult stem cells. The companys patent portfolio contains biotechnologies that solve the two main technical problems production and quantification that have stood in the way of successful commercialization of human adult tissue stem cells for cell medicine and drug development. Currently, ASCTC is employing its technological advantage to pursue commercialization of mass-produced therapeutic human liver cells and facile assays for screening-out drug candidates that are toxic to adult tissue stem cells.

Continue reading here:
The Adult Stem Cell Technology Center, LLC Announces Patent for Induced Pluripotent Stem Cells Produced with a Single ...

Time-lapse study reveals bottlenecks in stem cell expansion

PUBLIC RELEASE DATE:

12-Jun-2014

Contact: Hannah Postles h.postles@sheffield.ac.uk 01-142-221-046 University of Sheffield

A time-lapse study of human embryonic stems cells has identified bottlenecks restricting the formation of colonies, a discovery that could lead to improvement in their use in regenerative medicine.

Biologists at the University of Sheffield's Centre for Stem Cell Biology led by Professor Peter Andrews and engineers in the Complex Systems and Signal Processing Group led by Professor Daniel Coca studied human pluripotent stem cells, which are a potential source of cells for regenerative medicine because they have the ability to produce any cell type in the body.

However, using these stem cells in therapies is currently hampered by the fact they can acquire genetic changes during prolonged culture which are non-random and resemble mutations in cancer cells.

Researchers used time-lapse imaging of single human embryonic stem cells to identify aspects of their behaviour that restrict growth and would be targets for mutations that allow cells to grow more efficiently.

Dr Ivana Barbaric, from the University of Sheffield's Department of Biomedical Science, said: "We study pluripotent stem cells, which have huge potential for use in regenerative medicine due to their ability to become any cell in the human body. A pre-requisite for this is maintaining large numbers of undifferentiated cells in culture. However, there are several obstacles such as cells tend to die extensively during culturing and they can mutate spontaneously. Some of these genetic mutations are known to provide stem cells with superior growth, allowing them to overtake the culture a phenomenon termed culture adaptation, which mimics the behaviour of cancer cells.

"In order for pluripotent stem cells to be used safely in regenerative medicine we need to understand how suboptimal culture conditions, for example culturing cells at low split ratios, affect the cells and can lead to culture adaptation."

The team's research combined the use of time-lapse microscopy, single-cell tracking and mathematical modelling to characterise bottlenecks affecting the survival of normal human embryonic stem cells and compared them with adapted cells.

See the original post:
Time-lapse study reveals bottlenecks in stem cell expansion