« February 2011 | Main | April 2011 »

8 posts from March 2011

March 24, 2011

Tiny zebrafish shows how kidney regeneration could be achieved

This content has moved!

Please read this article on its new home, Signals BlogTiny zebrafish shows how kidney regeneration could be achieved

March 22, 2011

New technologies in stem cell biology and a call to reach back in time

by David Kent

I recently attended a special conference on Stem Cells, Development, and Cancer run by the American Association for Cancer Research (AACR) where Connie Eaves from the British Columbia Cancer Agency chaired a session entitled “Emerging Technologies” and said something that rang very true to me. She challenged the audience to read the papers from their field that were written many years ago and look for the ideas and hypotheses being tested and ask themselves how similar they are to those being pursued today – they simply lacked the tools to address them. In short, she made a very strong case for the importance of novel technologies and for biologists to be particularly tuned in to new developments and how they can impact their research. Anecdotally, I was once asked by Connie in my PhD to read a particular paper on the heterogeneity of blood cell progeny that, to my surprise, spelled out many of the theories and questions I was pursuing in my own studies. From a theoretical perspective, the testing framework had all been outlined in this paper and practically carried out in a more mature cell compartment. The really humbling part was that this particular report was published in 1982… when I was one. What has changed, of course, is that emerging technologies (in this case, the ability to isolate highly enriched fractions of stem cells and cell culture conditions to keep them alive and in the stem cell state) have made it possible to find answers to these questions, which has moved our understanding of stem cells forward. However, it is interesting to note that the researchers from 1982 would have happily done the same experiments if they’d only had the tools at their disposal.

Continue reading "New technologies in stem cell biology and a call to reach back in time" »

March 17, 2011

Aussies review embryonic and cloning legislation

by Ubaka Ogbogu

The Australian government is currently reviewing their stem cell and cloning research laws. The review, which began on December 22, 2010 with the appointment of an independent Legislation Review Committee (LRC) chaired by a retired federal judge, is the second since the enactment in 2002 of the Prohibition of Human Cloning for Reproduction Act and the Research Involving Human Embryos Act. The Australian Parliament amended both statutes in 2006, following an initial review mandated by each statute. The amended statutes contain provisions that require the Australian Minister of Mental Health and Aging to undertake further legislative reviews. These provisions instruct the reviewers to consider, among other things, medical and scientific development in embryonic stem cell research andthe actual or potential clinical and therapeutic applications of such research.”

Results from a government survey conducted in 2010 showed that the majority of Australians are in favour of stem cell research using both adult and embryonic stem cells. This report was one of the documents submitted to the LRC by the Australian Stem Cell Centre (ASCC) as part of their recommendations in support of the current regulatory framework. The ASCC submission includes five key recommendations:

Continue reading "Aussies review embryonic and cloning legislation" »

March 15, 2011

At long last… a national cord blood bank for Canada

Yesterday the Ministers of Health for the Provinces and Territories of Canada announced an investment of CAD $48M over eight years to establish a national umbilical cord blood bank for Canada. This is a very welcome, and some might say, overdue investment for which many organisations in the stem cell field have been advocating for some time.

Blood and marrow (stem cell) transplantation is an important tool in the treatment of some leukemias, disorders of the blood making system (aplastic anemia, thalassemia, sickle cell anemia) and is now being piloted for the treatment of some immune and metabolic disorders such as Crohn’s, multiple sclerosis and diabetes. This process relies on the ability to identify a donor who has an identical or near identical immune system. While a brother/sister has a one in four chance of being a match, most Canadians do not have a suitable family donor due to small family size, and currently there are around 800 patients waiting for a transplant according to Canada’s unrelated bone marrow donor registry (OneMatch.ca). 

Umbilical cord Blood is a rich source of stem cells and can be used as an alternative to adult bone marrow or blood. However, in the absence of a public cord blood bank, Canada has had to import all of the cord blood used in the treatment of these diseases, at an average cost of CAD $37,000 per cord according to Canadian Blood Services. Last year 96 such transplants were performed in Canada. However, many more potential patients were left untreated because they were unable to find a match. The multicultural melting pot in which we all live and take pride in as Canadians also means Canada is one of the most genetically diverse countries in the world, and as a consequence immune matches can be difficult to find. For example, Canada’s indigenous Métis peoples are not represented in the cord blood banks of other nations. It is on these groups that Canada’s newly funded Cord Blood Bank will focus, in order to ensure that these potentially life saving therapies are available to all Canadians, regardless of their heritage.

 

March 09, 2011

Is great science sitting on a shelf?

Patenting report shows disconnect in Canada

OldbooksXSmall


by Paul Krzyzanowski

Got a patentable idea? You might want to move to Switzerland. A recent article in the Globe and Mail compared Canada's patenting activity to other major countries, and the small European nation came out a clear winner.

2010 was a record year for US patents issuances to countries around the world. The Globe reported that US patents granted to Canadian applicants increased by 20 per cent – a commendable increase, until one notices that this was still behind those granted to applicants from other countries like Japan (up 26 per cent), Germany (up 25 per cent), South Korea (up 26 per cent) or the U.S. itself (up 24 per cent).  It’s possible that these across-the board increases simply represent a backlog of patents created by the 2008 credit crisis, but since total U.S. patent grabs have increased annually each year since 2007 it suggests that the recent poor economic conditions didn’t affect patenting activity drastically.

Continue reading "Is great science sitting on a shelf?" »

March 07, 2011

Art, science and the perceptions of promise

What role does art play in communicating science? It's a question that has been asked and studied rather extensively and it was one of the topics raised during the POP/SCIENCE panel discussion at the Glenbow Museum in Calgary last Thursday. The event was held in conjunction with the Perceptions of Promise art exhibit, currently running at the Glenbow until March 20.

 

Scientists themselves are wary and somewhat concerned about the accuracy of artistic and pop culture interpretations of stem cell science. But, when it comes to newspaper reporting of stem cell and genetic research, studies have found that reporters are not doing a bad job, overall. As Timothy Caulfield suggested in his talk at the Understanding Stem Cell Controversies course, the over-optimism often begins with the scientists themselves, who are required to demonstrate or promise applicable results in order to compete for smaller slices of the research funding pie. So if 24's Jack Bauer can be cured of his prion disease using stem cells, is this error necessarily the fault of the script writers? No, but nor can the scientists be blamed, suggests Caulfield. In describing a clear path to the clinic, they are simply doing what is requested by the funding agencies, who are acting on dictates of government, who, in turn, are responding to the needs and desires of the public. And around it goes.

The bigger question is whether artists and mainstream media are required to be accurate in their portrayals of science. As the panel pointed out, the job of artists is not to relate the science accurately (and as panelist Karen Rothenberg intoned, if artists did represent science in a factual manner, the resulting artwork would be very boring), but to interpret and reflect on science through the lens of society. This is a question that has permeated society for a very long time -- and the boundaries are not always entirely clear. Consider, for instance, the anatomical drawings of Leonardo da Vinci, which presented an entirely new way for people -- including the scientists of the day -- to look at science and art in the context of their everyday lives. 

Nor are the roles of scientists and artists always so polarized and the Perceptions of Promise exhibit demonstrates this quite clearly. The workshop that launched the project brought artist and scientists together to explore, connect and ultimately to collaborate. Perhaps the most illustrative example of this are the stunning paintings by Daniela Schlüter, which incorporated the procedural sketches of stem cell scientist Paul Cassar. 

Art and popular media may not get it right, but they do get us thinking and talking about science in ways that cannot be achieved through traditional scientific channels. As art and science are both driven primarily by curiosity and a desire to understand, such opportunities for discussions should be welcomed -- no, encouraged -- as a means to provoke new and better scientific and artistic pursuits.

- Lisa Willemse, SCN Director of Communications

March 03, 2011

Are stem cells branded?

I've heard many different adjectives used to frame discussions of stem cells: powerful, promising, controversial, cutting edge, rejuvenating, mysterious, sexy, to name but a few. All of these descriptors are used in various ways to promote particular opinions, beliefs or imagery of stem cells and many of them, I would argue, are vastly overused and in some cases, quite misleading.

While sitting in the morning session at the Understanding Stem Cell Controversies course currently taking place in Calgary, I was introduced to a new adjective in the stem cell lexicon -- branded (and, oddly enough, this descriptor was used by two presenters, Brian Kwon and Timothy Caulfield). Can a word, typically attached to such concepts as corporate identity and customer loyalty, be used in relation to the broad field of stem cells? Of course it can. There may not be a logo to solidify that brand, but the adjectives I listed are, in essence, the brand of stem cells. 

At the heart of this morning's discussions was the use (or misuse) of the stem cell brand not just to sell stem cell products such as face creams and spa treatments, but also to instil a belief that stem cell therapies are a routinely available and the best choice to be made in treating otherwise incurable injuries or disease. As an orthopaedic surgeon, Brian Kwon noted that "every one of my patients asks about stem cell treatment".

In fact, Kwon's current research found that the number of spinal cord injury patients who would choose a stem cell treatment outnumbers those who would choose a conventional drug therapy (assuming that both treatment options exist). Think about it. A spinal cord stem cell treatment would be highly invasive, requiring a major operation, exposure of the spinal cord, injection of a needle into the spinal cord itself and possibly a prolonged course of immunosuppressants. Conventional drug therapies are typically administered either orally or intravenously. 

Kwon further noted that a 2009 sample of media reports about potential treatments for spinal cord injury all used the term "stem cell" as part of the news story, even when the treatment in question had nothing to do with stem cells whatsoever. See more of Kwon's presentation:

 

Since stem cells have thus far resisted any attempt to define ownership, the brand also defies any single entity's attempt to manage it. For the scientific community, this is troubling. Timothy Caulfield spoke about a current trend to shift the stem cell brand identity from a scientific and clinical framework to the realm of "alternative medicine". Such a shift would negate the authority of scientists in their attempts to raise awareness of the dangers of stem cell tourism by distancing them from public discussions on the issue. 

-- Lisa Willemse, SCN Director of Communications

March 02, 2011

Genomic instability in iPS cells

by Chris Kamel

They're promising, but not perfect. Induced pluripotent stem cells are perhaps one of the most studied areas of stem cell research today, as researchers work to improve their method of production, but new findings out of Canada and Finland suggests that the process of reprogramming may cause unwanted and irreversible DNA damage. As such, the rush to improve iPS cell generation may, in itself, be partially responsible for decreased integrity of the cells.

To date, several methods of reprogramming have been developed with the partial aim of improving the efficiency of iPS cell generation. The reprogramming process involves the introduction of a key set of genes which, along with turning terminally differentiated cells into stem cells, can alter other aspects of cell biology. For example, one of the genes involved in reprogramming, the oncogene c-Myc, can interact with p53 and p21 activities. This has a positive effect on reprogramming efficiency but can also lead to genomic instability.

One mark of genomic instability is copy number variation (CNV), an abnormal number of copies of DNA caused by the deletion or duplication of regions of the genome. The Canadian-Finnish paper, to be published tomorrow in Nature, demonstrated that human iPS cells have more CNVs than human ES cell lines, and that the number of CNVs decreased as the induced pluripotent cells were passaged in culture. These observations were independent of gene delivery method, original cell source, and the presence or absence of c-Myc, and suggest that generation of CNVs occurs with the reprogramming process. Focussing on copy number variation caused by genomic deletions, the authors found that in "young" iPS cell populations, many deletions were found in regions responsible for mainenance of an undifferentiated state in ES cells. As cells were passaged in culture, these deletions were not found indicating these cells were being selected against and overgrown.

The study demonstrates that the reprogramming process to generate iPS cells is associated with a high mutation rate. While selection deleterious mutations in culture brings the number of CNVs in line with those in human ES cells, it does not exclude the fact that some mutations may, in fact, offer selective advantage and lead to propagation of unwanted traits. The paper offers some new insights into the reprogramming mechanisms and potential downsides of the iPS approach. Better understanding of the reprogramming process and of the genomic integrity of iPS cell lines could lead to more efficient techniques and higher quality iPS cells for use in future research and therapeutic applications.