Showing posts with label hybrid. Show all posts
Showing posts with label hybrid. Show all posts

Monday, 2 February 2009

Animal Eggs Not Suitable Substitutes to Produce Stem Cells

Eggs of another species turns off the genes needed to make an embryo instead of turning them on Monday, 02 February 2009 Since the cloning of Dolly the Sheep over a decade ago, somatic cell nuclear transfer (SCNT) has been considered a promising way to generate human, patient-specific stem cells for therapeutic applications. The shortage of human donor eggs has led to efforts to substitute animal oocytes. However, a new study published online ahead of print in the Volume 11, Number 2, 2009 issue of Cloning and Stem Cells, demonstrates that animal oocytes lack the capacity to fully reprogram adult human cells. Robert Lanza, M.D. from Advanced Cell Technology (Worcester, MA), and colleagues compared the reprogramming of human cells using oocytes obtained from cows, rabbits, and humans. They report their findings in a paper entitled, "Reprogramming of Human Somatic Cells Using Human and Animal Oocytes." “Mixing human and animal cells does not appear to program the egg properly,” said Dr. Robert Lanza in an interview with Reuters. "For the last decade, we've carried out literally hundreds of experiments trying to create patient-specific stem cells using animal eggs," Lanza said. "We got beautiful little hybrid embryos, but it didn't work no matter how hard we tried." The ability to reprogram human cells using oocytes would enable the production of patient-specific stem cells that could then be differentiated to become any type of somatic cell and used for cell or tissue repair or placement therapy. This extensive reprogramming requires that the oocyte turn on, or up-regulate a large number of genes in the donor nucleus. Although previous reports have documented the formation of cloned embryos using both human and animal eggs, to date, there have been no data indicating to what extent the donor human DNA was reprogrammed. Lanza et al. show for the first time that human oocytes have the capacity to change these patterns of gene expression, and that interspecies (human-to-animal) cloning does not produce the same results. Although the human-bovine and human-rabbit clones looked similar to the human-human embryos, the human-animal hybrids did not exhibit the changes in gene expression seen in the human-human clones and normal embryos. A mouse-human hybrid petered out after just one division. The cow and rabbit human hybrids went further, but stopped at the point when maternal DNA is supposed to kick in and turn the ball of cells into a proper embryo, Lanza said. Lanza's team used a new method called global gene expression analysis to see which genes were turned on and off as the eggs grew. "We never had the tools before to actually look inside the cell and see what's going on," Lanza said. It appears that using the egg of another species turns off the genes needed to make an embryo instead of turning them on, he said. But the human-human clone did turn on the right genes, although it, too stopped dividing before it could produce stem cells, Lanza said. "We see exactly the same genes turned on in a normal embryo are actually turned on in a human clone," he said. “We examined the factors recently used to reprogram skin cells (to induce pluripotent stem cells),” said Robert Lanza. “At the center of cellular reprogramming lies the activation of the transcription factors Oct4, Sox2, and Nanog. These core factors were activated in both the normal and cloned human embryos. In striking contrast, the human-animal hybrids showed no difference or a down-regulation of these critical pluripotency genes −effectively silencing them — thus making the generation of stem cells impossible. Without appropriate reprogramming, these data call into question the potential use of animal egg sources to generate patient-specific stem cells. It also renders the moral controversy surrounding the use of human-animal hybrids mute.” Specifically, they did not achieve up-regulation of these critical pluripotency-associated genes needed for stem cell production. For example, human oocytes significantly up-regulated Oct-4, Sox-2, and Nanog (22-fold, 6-fold, and 12-fold, respectively), whereas the bovine and rabbit oocytes either showed no difference or a down-regulation of these critical pluripotency-associated genes, effectively silencing them. "This very important paper suggests that livestock oocytes are extremely unlikely to be suitable as recipients for use in human nuclear transfer. This is very disappointing because it would mean that production of patient-specific stem cells by this means would be impracticable," says Ian Wilmut, Ph.D., Editor-in-Chief of Cloning and Stem Cells and director of the Centre for Regenerative Medicine, in Edinburgh. Reference: Reprogramming of Human Somatic Cells Using Human and Animal Oocytes Young Chung, Colin E. Bishop, Nathan R. Treff, Stephen J. Walker, Vladislav M. Sandler, Sandy Becker, Irina Klimanskaya, Wan-Song Wun, Randall Dunn, Rebecca M. Hall, Jing Su, Shi-Jiang Lu, Marc Maserati, Young-Ho Choi, Richard Scott, Anthony Atala, Ralph Dittman, Robert Lanza Cloning and Stem Cells. ahead of print, doi:10.1089/clo.2009.0004 ......... ZenMaster


For more on stem cells and cloning, go to CellNEWS at http://cellnews-blog.blogspot.com/ and http://www.geocities.com/giantfideli/index.html

Thursday, 4 September 2008

Changes to Embryonic Stem Cells Caused by Down Syndrome

Changes to Embryonic Stem Cells Caused by Down Syndrome Thursday, 04 September 2008 Scientists investigating the mechanisms of Down Syndrome (DS) have revealed the earliest developmental changes in embryonic stem cells caused by an extra copy of human chromosome 21 – the aberrant inheritance of which results in the condition. Their study is published online today (Thursday 4 September) in the American Journal of Human Genetics. Lead by Dean Nizetic, Professor of Cellular and Molecular Biology at Barts and The London School of Medicine and Dentistry, the team utilised embryonic stem cells from a previously genetically engineered species of mice carrying a copy of human chromosome 21. They discovered that extra chromosome 21 - a genetic state known as trisomy 21 - disturbs a key regulating gene called NRSF or REST, which in turn disturbs the cascade of other genes that control normal development at the embryonic stem cell stage. Furthermore, they identified one gene (DYRK1A) on human chromosome 21, whose overdose in trisomy (DS) is responsible for the observed effects. Down Syndrome belongs to the group of conditions called 'aneuploidies', defined by an abnormal loss or gain of genetic material, i.e. fragments of chromosomes or whole chromosomes. Aneuploidies cause congenital anomalies that are a prime cause of infant death in Europe and the USA, and are currently on the increase with advancing maternal age in European countries. The number of people with DS in Europe exceeds half a million. The condition is more common than muscular dystrophy and cystic fibrosis. However, the development of new therapeutic concepts is hindered by the fact that unlike muscular dystrophy and cystic fibrosis, where a single mutated gene causing the disease is known, the entire human chromosome 21 (containing around 300 genes) still has to be dissected into individual gene-dose contributions to the DS symptoms. Professor Nizetic, calling for further research into the components of the disturbed cascade he and his team have revealed said: "We hope that further research might lead to clues for the design of new therapeutic approaches tackling developmental delay, mental retardation, ageing and regeneration of brain cells, and Alzheimer's disease. In other words, we hope our work will open new routes to tackle the genetics of these health disorders, approaching them from the "back entrance", as dominant component-symptoms of Down Syndrome." Reference: DYRK1A-Dosage Imbalance Perturbs NRSF/REST Levels, Deregulating Pluripotency and Embryonic Stem Cell Fate in Down Syndrome Claudia Canzonetta, Claire Mulligan, Samuel Deutsch, Sandra Ruf, Aideen O'Doherty, Robert Lyle, Christelle Borel, Nathalie Lin-Marq, Frederic Delom, Jürgen Groet, Felix Schnappauf, Serena De Vita, Sharon Averill, John V. Priestley, Joanne E. Martin, Janet Shipley, Gareth Denyer, Charles J. Epstein, Cristina Fillat, Xavier Estivill, Victor L.J. Tybulewicz, Elizabeth M.C. Fisher, Stylianos E. Antonarakis, Dean Nizetic The American Journal of Human Genetics, 04 September 2008, 10.1016/j.ajhg.2008.08.012 ......... ZenMaster


For more on stem cells and cloning, go to CellNEWS at http://cellnews-blog.blogspot.com/ and http://www.geocities.com/giantfideli/index.html

Tuesday, 5 August 2008

Progress of China's Stem Cell Research

Impressive Scope of Chinese Stem Cell and Regenerative Medicine Research Tuesday, 05 August 2008 To get an assessment of how extensive and serious stem cell research has become in China proper, it is only to look through the proceedings from Shanghai International Symposium on Stem Cell Research, held in November 2007, and published in Cell Research (Volume 18, Issue S1, August 2008) today. The organisers write: “the topics of the representations covered: adult stem cells; embryonic stem cells; stem cell niche and regulation; reprogramming, epigenetics and cloning; directed stem cell differentiation; stem cells and diseases; global issues of stem cell research: ethics, international collaborations and publications.” Several hundreds of Chinese researchers (and Chinese born scientists from other countries) participated in the meeting, which show a truly impressive wide range and scope of the Chinese efforts in stem cell research and regenerative medicine. The symposium was co-organized by the Key Laboratory of Stem Cell Biology, Shanghai Institutes for Biological Sciences; the Chinese Academy of Sciences (CAS); Shanghai Jiaotong University School of Medicine; Fudan University; Beijing University Stem Cell Research Center; and Guangzhou Institutes of Health and BioMedicine of CAS, together with the International Society for Stem Cell Research (ISSCR). This is in stark contrast to the recently held China Stem Cell Technology Forum in Taizhou (see Stem Cell Forum in China Demonstrate Cutting Edge Research), which only tried to promote the questionable practices of Beike Biotechnology Co., Ltd.. Reference: Abstracts from 2007 Shanghai International Symposium on Stem Cell Research Cell Research Volume 18, Issue S1, August 2008 ......... ZenMaster


For more on stem cells and cloning, go to CellNEWS at http://cellnews-blog.blogspot.com/ and http://www.geocities.com/giantfideli/index.html

Tuesday, 1 July 2008

HFEA Licence Human-pig Hybrid Embryos

HFEA Licence Human-pig Hybrid Embryos 
Tuesday, 01 July 2008 

A licence to create human-pig embryos to study heart disease has been issued by the British fertility watchdog the Human Fertilisation and Embryology Authority. This is the third animal-human hybrid embryo licence to be issued by HFEA and the first since the Commons voted in favour of this controversial research last month. An HFEA spokesman said it had approved an application from the Clinical Sciences Research Institute, University of Warwick, for the creation of hybrid embryos. 

The centre has been offered a 12 month licence with effect from today, July 1. The Licence Committee was satisfied that the research was permissible within the law and met the criteria required by the 1990 Human Fertilisation and Embryology Act. 

The effort at the University of Warwick is led by Professor Justin St John

"This new license allows us to attempt to make human pig clones to produce embryonic stem cells," he said to The Telegraph. 

 He will study mutation for certain kinds of cardiomyopathies, which make the heart lose its pumping strength. He researchers will mainly study the power-houses of cells, the mitochondria, and genetic defects that affect their ability to support heart cells. 

 Teams in Newcastle and London are already creating hybrids. The former have already created hybrids with cow eggs to study the basics of how the use of genes changes in early development, the latter a range of species to generate stem cells from people with neurodegenerative disorders. 
......... 

ZenMaster


For more on stem cells and cloning, go to CellNEWS 
at http://cellnews-blog.blogspot.com/

Sunday, 18 May 2008

Gordon Brown Urges Support for Embryo and Stem Cell Research

Gordon Brown urges support for embryo and stem cell research Sunday, 18 May 2008 Scientists should be given the legal framework necessary to pursue cures for diseases like Parkinson's, Alzheimer's and cancer, the British PM Gordon Brown has said. Writing in the Observer newspaper today, Mr Brown said "we owe it to ourselves and future generations" to allow scientists to use properly regulated stem cell research. He said providing clear laws for researchers could save "millions of lives". Adult stem cells are already being used in treatments for conditions including leukaemia and heart disease. Scientists are close to breakthroughs that will allow embryonic stem cells to be used to treat a much wider range of conditions, especially those affecting the brain and nervous system. Mr Brown said that he has "deep respect" for those opposed to the research on religious grounds, and the proposed legal framework has been designed to be as clear as possible. The use of 'human admixed embryos', where human and animal genetic material is used together, will address the shortage of embryonic stem cells, he explained. "Let me be clear: if we want to sustain stem cell research and bring new cures and treatments to millions of people, I believe admixed embryos are necessary. The question for me is not whether they should exist, but how their use should be controlled." Read more: Why I believe stem cell researchers deserve our backing The Observer - Sunday May 18 2008 UK Department of Health Stem Cell pages ......... ZenMaster


For more on stem cells and cloning, go to CellNEWS at http://cellnews-blog.blogspot.com/ and http://www.geocities.com/giantfideli/index.html

Wednesday, 14 May 2008

Study on Attitudes to Stem Cell Research

BBVA Foundation international study on attitudes to stem cell research Wednesday, 14 May 2008 Unlike most scientific and technological advances, which tend to take their place silently in society, biotechnology often finds itself the center of public debate and regulatory attention, due partly to the moral issues posed by many of its applications. In this second BBVA Foundation international study on “Attitudes to Biotechnology” (the first was in 2003), the sample has been enlarged from nine to twelve European countries (Austria, Czech Republic, Germany, Denmark, Spain, France, Ireland, Italy, Netherlands, Poland, United Kingdom and Sweden), with the addition of countries from other continents; namely the United States, Japan and Israel. The selection of countries was informed by both their demographical weight and their variability from the standpoint of religious beliefs and cultural traditions. Information was gathered through 1,500 face-to-face interviews in each country with subjects aged 18 and over (around 22,500 interviewees in all) conducted between April 2007 and February 2008. The design and analysis of the survey were the work of the Department of Social Studies and Public Opinion of the BBVA Foundation. The present study focuses on attitudes towards one biotechnology application: research with embryos for the purpose of obtaining stem cells. In particular, it analyzes how far public opinion is informed about stem cells, expectations and reservations regarding research with embryonic stem cells and differences in support for such research depending on the origin of the embryos used. Attention also goes to the attitudes held on the creation of hybrid embryos for stem cell research. PUBLIC UNDERSTANDING OF THE NATURE OF STEM CELLS The data show that the percentage of the population that admit having heard or read anything about this kind of cell was notably uneven across the survey countries: over 70% had heard or read about stem cells in Sweden and Denmark (86%), and also the United Kingdom, Netherlands and United States (between 70% and 75%); and over 55% in Italy, France, Ireland, Spain, the Czech Republic and Germany: while awareness of stem cells was less than 45% in Poland, Austria, Israel and Japan. As well as information about stem cells, the survey enquired about how far citizens understood the properties of such cells and the procedures used for obtaining them. The results point to a moderate understanding of stem cell properties: surpassing 50% in seven of the fifteen countries, between 40% and 50% in another four and below this threshold in the four remaining (Austria, Poland, Japan and Israel). In contrast, people had a poor understanding about how stem cells are extracted and the consequences for the embryo, with percentages no higher than 30% in the United States, between 15% and 20% in a further six countries and lower still in the remainder. VIEWS ABOUT RESEARCH WITH STEM CELLS In most societies there is a broad consensus around the usefulness of research with few-day-old human embryos in order to obtain stem cells. The mean agreement score with the idea that such research is very useful stood higher than the midpoint (5 on a scale from 0 to 10) in all countries except Austria, and was upwards of 6 points in nine of the fifteen countries, with Denmark and Sweden out in front. But this overall perception of usefulness does not rule out feelings of risk or moral dilemmas. Hence the data show considerable reservations about the risks entailed by researching with human embryos that are a few days old for the purpose of obtaining stem cells. There is general disagreement with the idea that this application poses no serious risks, with mean agreement scores below the midpoint (5) in eleven of the fifteen countries. The citizens perceiving least risk are the Danish and the Dutch, with Austrians, Americans and Japanese lined up at the other extreme. The moral or immoral nature of the application meets with divided opinions among survey countries. The majority view in Austria, Germany, Poland, Japan, Israel and United States is that this kind of research is immoral (mean agreement score above the midpoint on the scale), while those most strongly disagreeing with this supposed immorality are the citizens of Denmark, Spain, the United Kingdom and Italy (mean agreement score below the midpoint). Finally, opinions tend to cluster round the midpoint in the remainder of countries. POSSIBLE MEDICAL BENEFITS Debate and regulations regarding research with embryonic stem cells try to weigh up the medical benefits that may be obtained in future (the end pursued) against the moral reservations felt about this kind of research (the means utilized). When the possible medical benefits deriving from stem cell research are opposed in abstract terms to the rights of the embryo, opinions are divided both between and within countries:

  • In Spain, the Czech Republic, Sweden, Denmark, France and the Netherlands, the balance leans to a greater or lesser extent towards the side of medical benefits. Hence the majority agree with the statement that “the medical benefits for many human beings that can perhaps be obtained in the future thanks to research with embryos that are a few days old are much more important than the embryos' rights”.
  • In Austria, Ireland, Germany, Poland, the United States, Japan and Israel, the balance inclines more or less (depending on the country) towards the rights of embryos: that is, a majority dissent from the idea that “the medical benefits for many human beings that can perhaps be obtained in the future thanks to research with embryos that are a few days old are much more important than the embryos' rights”.
  • Finally, the balance is more centered (mean value of 5) in the United Kingdom and Italy.

When the potential medical benefits are spelled out as treatments for what are seen as serious diseases (Parkinson's, Alzheimer's or diabetes), a majority in all countries declare themselves in favour of such research. The mean agreement with the assertion that “research with stem cells from embryos that are a few days old should be supported as a means of finding effective treatments for diseases such as Parkinson's, Alzheimer's or diabetes as soon as possible” was above the midpoint in every country with the exception of Austria, and exceeded 6 points in nine cases, with Spanish and Czech citizens agreeing most strongly. Besides moral objections, this kind of research meets with other reservations to do with ideas of what is natural or unnatural and concern about interfering with or altering the balance of nature. Citizens in most of the survey countries tended to agree that “research with human embryos that are a few days old is an unacceptable interference into the natural processes of life”, with agreement being firmest in Germany, Austria, Poland and Israel. There is also widespread concern that this kind of research may lead to other more dubious uses. The idea that “allowing research with embryos that are a few days old in order to obtain stem cells for use in medicine will open the door to other morally reprehensible uses” meets with considerable approval even in the countries favourably disposed to this application. The consensus round this view is especially marked in France, Germany and Japan. At the same time, research using embryonic stem cells touches on the moral or ethical framework of each individual, and in this sense moral criterion of religious inspiration is a key explanatory vector. In a context of plural opinions, the data show that the dominant view of the moral condition of the few-day-old human embryo is that it is close or identical to that of a human being. The strictly biological view finds widest support in Denmark and Sweden, where opinions are more equally distributed between those believing it makes no sense to talk about a moral condition of the embryo and those seeing it as close or identical to a human being. This view of the embryo as close or identical to a human is most frequently expressed in countries such as Austria, Germany and the United States. In Spain, opinions are quite sharply divided: 27% state that it makes no sense to talk about the moral condition of an embryo that is a few days old, while 25% take the intermediate position and another 35% see its moral condition as close or identical to that of a human being. ACCEPTANCE OF THE USE OF EMBRYOS DEPENDING ON THEIR ORIGIN Public debate and regulatory attention concerning research with stem cells has recently crystallized around two concrete scenarios: the use of spare embryos left over from fertility treatments and the use of embryos created specifically for biomedical research purposes. Citizens in most survey countries make differing judgments on these two scenarios, with acceptance of the use of spare embryos in all cases greater than that of embryos created for research. In the case of spare embryos, mean scores were in the approval zone in all countries except Austria (4.4) and Japan (4.6), and stood higher than 6 points in Denmark, Sweden, the Czech Republic, the Netherlands and Spain. In the case of embryos created for research, scores tended to range from 4 to 5 points, with support only at all emphatic in the Czech Republic (6.2). The citizens of Spain, Italy, the United Kingdom and Poland expressed marginal approval (just scraping in above 5 points on the scale) while remaining countries were all in the rejection zone. CREATION OF HYBRID EMBRYOS Faced with a shortage of human embryos for use in advancing stem cell research, British scientists have sought official permission to create hybrid embryos. In September 2007, the UK agency regulating embryo research and fertility treatments (Human Fertilization and Embryology Authority) approved the creation of hybrid embryos for the purpose of obtaining stem cells for biomedical research. The technique in question involves the implanting of the nucleus of an adult human cell into the egg of an animal from which the nucleus has been previously extracted. The BBVA Foundation survey also questioned citizens about their attitudes to such advances. The creation of hybrid embryos causes divided reactions both between and within countries. The baseline scenario meets with attitudes of rejection (below 5 on an acceptance scale from 0 to 10) in most of the countries studied. Only in the Czech Republic, Spain, Italy, Israel and Denmark does the mean score approach the midpoint on the scale. The citizens of Poland, France, Austria and Germany are the most critical of this application. Predominant in most countries is the fear that the technique could get out of control and lend itself to dangerous uses. This feeling appears to run deepest in Poland, France, Austria and Israel. A rather different reaction emerges in Denmark, the Netherlands and Sweden, where rejection of the creation of hybrids appears to have less to do with fear, and possibly more to do with perceptions that it is interfering with nature. .........

ZenMaster
For more on stem cells and cloning, go to CellNEWS at http://cellnews-blog.blogspot.com/ and http://www.geocities.com/giantfideli/index.html

Tuesday, 13 May 2008

Genetically Modified Human Embryo Stirs Controversy

Scientists create first GM human embryo 
Tuesday, 13 May 2008 

Researchers at Cornell University in New York have made a breakthrough in genetics by creating the first genetically modified (GM) human embryo. The GM embryo was produced to study how early cells in the embryo develop, but the scientists destroyed it just after five days. Led by Nikica Zaninovic, researchers at Cornell University used a virus to add a gene, a green fluorescent protein, to an embryo left over from assisted reproduction. It is believed to be the first documented genetic modification of a human embryo. 

Zaninovic's achievement was announced at the American Society for Reproductive Medicine annual meeting in 2007, but was only publicized recently when the United Kingdom's reproductive technology regulators reviewed the research. One of the authors of the study said to AP that the work was focused on stem cells. He noted that the researchers used an abnormal embryo that could never have developed into a baby anyway. 

"None of us wants to make designer babies," said Dr. Zev Rosenwaks, director of the Center for Reproductive Medicine and Infertility at New York-Presbyterian/Weill Cornell Medical Center. Dr. Rosenwaks said the research had been approved by a review board at his medical center and been privately financed, so it did not violate federal restrictions on research involving human embryos. 

 Doctors already put foreign genes into people as part of gene therapy to treat diseases. But those genetic changes generally cannot be passed on to future generations because they are made to only certain types of cells in the body, like blood cells or muscle cells. Genetic changes made to an embryo would theoretically be heritable if the embryo became a baby. So far, this has been a no-go area for scientists and medical professionals. 

 The breakthrough has brought with it major concerns. The British regulator, the Human Fertilisation and Embryology Authority (HFEA), has even cautioned that such controversial experiments may lead to "large ethical and public interest issues". However, the HFEA has said that it is preparing for scientists to apply for licences to create GM embryos. 

A paper, published by the authority, states: “The bill has taken away all inhibitions on genetically altering human embryos for research. The Science and Clinical Advances Group [of the HFEA] thought there were large ethical and public interest issues and that these should be referred for debate.” 

 The House of Commons in Britain is about to consider legislation permitting this and other controversial reproductive technologies, such as the creation of chimeras – human-animal hybrid embryos. The first voting on this Bill took place yesterday in the British Parliament. There the MPs voted to allow, with a great majority, the plan to update the human embryology laws to continue to their next Parliamentary stage. The research raises a number of difficult ethical questions. 

Though adding a fluorescent protein was merely a proof-of-principle step, modified embryos could be used to research human diseases. Scientists say embryos wouldn't be allowed to develop for more than a few weeks, much less implanted in a woman and brought to term. If the embryos were allowed to develop, genetic modifications – which would be permanent and passed to future generations – might prevent disease. 

Modifications might also be used for other reasons – physical appearance, intellectual prowess and personality changes – though the necessary science remains hypothetical at this point. Developing such techniques would necessarily involve at this stage trial-and-error and risk-taking with human life.

Let's have that debate:
What do you think CellNEWS readers? 

  • Should genetically modified human embryos be used in research, or reproduction? Both? Neither? 
  • What would be the advantages or disadvantages? 
  • Would it OK to produce ‘designer babies’ in the future, when the technique is perfected? 

Reference: 
N. Zaninovic, J. Hao, J. Pareja, D. James, S. Rafii, Z. Rosenwaks. 
ASRM 2007 Annual Meeting, Poster session. 

Other Online Resources: 
HFEA 
......... 

ZenMaster

For more on stem cells and cloning, go to CellNEWS 
at http://cellnews-blog.blogspot.com/

Wednesday, 2 April 2008

Human-animal Hybrid Embryos Created in Newcastle

Human-animal Hybrid Embryos Created in Newcastle Wednesday, 02 April 2008 Britain's first human-animal hybrid embryos have been created, forming a crucial first step, scientists believe, towards a supply of stem cells that could be used to investigate debilitating and so far untreatable conditions such as Alzheimer's disease, Parkinson's and motor neurone disease. Lyle Armstrong, who led the work, gained permission in January from the Human Fertilisation and Embryology Authority (HFEA) to create the embryos, known as "cytoplasmic hybrids". He presented the preliminary findings of the project at a conference at the Sennet in Israel the 25th March 2008. His team at Newcastle University produced the embryos by inserting human “banked” cells - derived from a human embryonic stem cell line from Newcastle (Ncl-1) - into a hollowed-out cow egg. An electric shock then induced the hybrid embryo to grow. The embryo, 99.9% human and 0.1% other animal, grew for three days, until it had 32 cells. Eventually, scientists hope to grow such embryos for six days, and then extract stem cells from them. The researchers insisted the embryos would never be implanted into a woman and that the only reason they used cow eggs was due to the scarcity of human eggs. John Burn, head of the Institute of Human Genetics at Newcastle University, said the embryos had been created purely for research and that the research is entirely ethical. He told the BBC's Six O'Clock News last night: "If you look down the microscope it looks like semolina and it stays like that. It's never going to be anything other than a pile of cells. What it does is give us the tools to find out the simple questions: how can we better understand the disease processes by working with those cells in the body?" "This is licensed work which has been carefully evaluated. This is a process in a dish, and we are dealing with a clump of cells which would never go on to develop. It's a laboratory process and these embryos would never be implanted into anyone.” "We now have preliminary data which looks promising but this is very much work in progress and the next step is to get the embryos to survive to around six days when we can hopefully derive stem cells from them." The research has not yet been published, but the team plans to submit the work for peer review in the coming months. Other scientists welcomed the work but also urged caution in interpreting the results. Colin Blakemore, a former head of the Medical Research Council, said: "The creation of hybrid embryos is not illegal and researchers in Newcastle and London were granted provisional licences for such research in January, after extensive consultation by the HFEA ... This research is at a very early stage and no results have been peer-reviewed or published.” "However, these preliminary reports give hope that this approach is likely to provide stem cells for research without the use of human eggs or normal human embryos. The new bill is intended to confirm the arrangements for regulation of this important area of research."

See more:

Scientists create Britain's first hybrid embryos Independent, UK - April 2 2008 British scientists create human hybrid Guardian, UK - April 2 2008 Embryo breakthrough ITN, UK - April 2 2008 British team makes mixed human animal embryos Times Online, UK - April 2 2008 Hybrid embryos made by UK scientists Telegraph, United Kingdom - April 1 2008 UK's first hybrid embryos created BBC News, UK - April 1 2008 ......... ZenMaster


For more on stem cells and cloning, go to CellNEWS at http://www.geocities.com/giantfideli/index.html

Tuesday, 5 February 2008

Three Parent Embryos Created

Three Parent Embryos Created - Again! Tuesday, 05 February 2008 Ten human embryos each containing the DNA from one man and two women have been created in a project that within three years could lead to the first genetically altered babies being born in Britain. The aim is to treat mitochondrial disorders, inherited diseases that can include fatal liver failure, stroke-like episodes, mental retardation with intractable epilepsy, muscle weakness, diabetes and deafness. All cells of the body have many (typically 1000-10,000) mitochondria. Mitochondria are tiny energy-producing structures ('organelles', the cell's equivalent to organs of the body) vital to cell function. If they malfunction then organs will eventually fail. The mitochondria are transmitted to the next generation through eggs, but not via the sperm, so mitochondrial defects are only inherited from the mother. The Newcastle team would take a one-day old IVF embryo from a couple at risk of mitochondrial disease, when the DNA cargoes from the sperm and egg are still separate and sit in structures called pronuclei. Then they would remove these pronuclei and insert them into an emptied egg from a second woman, which contains healthy mitochondria. The resulting early embryo would contain DNA from the parents in the nucleus, plus the mitochondria from the egg donor. If implanted back into the mother and a girl were born in this way, the inserted mitochondria would be passed to future generations to free them of potentially deadly disorders, too. Boys would not pass on the implanted mitochondria, because sperm do not contain mitochondria. Professor Patrick Chinnery, a member of the Newcastle team, said: "We believe that from this work, and work we have done on other animals that in principle we could develop this technique and offer treatment in the foreseeable future that will give families some hope of avoiding passing these diseases to their children." This procedure has been performed successfully previously (see Three Parent Embryo’s Created, CellNEWS - Wednesday, 15 October 2003). Articles: Transplant creates embryos with three parents Telegraph - Last Updated: 12:01am GMT 05/02/2008 Three-parent embryo formed in lab BBC - Last Updated: Tuesday, 5 February 2008, 11:13 GMT Scientists create three-parent embryos Reuters - Tue Feb 5, 2008 11:17am EST ......... ZenMaster
For more on stem cells and cloning, go to CellNEWS at http://www.geocities.com/giantfideli/index.html

Friday, 18 January 2008

UK HFEA Approves Human-Animal Hybrid Embryo Research

UK HFEA Approves Human-Animal Hybrid Embryo Research Friday, 18 January 2008 The Human Fertilisation and Embryology Authority (HFEA) yesterday granted permission to two groups of scientists to create human-animal embryos for research. Two centres, King's College London and Newcastle University, will now be able to begin their work under one-year research licences. Scientists from the two centres submitted applications last year to create human stem cells using animal eggs. The process involves injecting an empty cow or rabbit egg with human DNA. A burst of electricity is then used to trick the egg into dividing, so that it becomes a very early embryo from which stem cells can be extracted. "The HFEA License Committee determined that the two applications satisfied all the requirements of the law," the agency said. Scientists want to create hybrid embryos by merging human cells with animal eggs in a bid to extract stem cells. The embryos would then be destroyed within 14 days. At the moment, scientists in the UK have to rely on human eggs left over from fertility treatment, but they are in short supply and are not always good quality. Dr Stephen Minger and colleagues at King's College London want to create hybrids to study diseases known to have genetic causes — such as Alzheimer's disease, spinal muscular atrophy and Parkinson's disease. Dr. Lyle Armstrong's team at The Northeast England Stem Cell Institute, Newcastle University, are planning to use the technique to help understand how stem cells differentiate into different tissues in the body. Dr Armstrong said: "Now that we have the licence we can start work as soon as possible.” "We have already done a lot of the work by transferring animal cells into cow eggs so we hope to make rapid progress." "Finding better ways to make human embryonic stem cells is the long-term objective of our work and understanding reprogramming is central to this." "Cow eggs seem to be every bit as good at doing this job as human eggs so it makes sense to use them since they are much more readily available but it is important to stress that we will only use them as a scientific tool and we need not worry about cells derived from them ever being used to treat human diseases." Professor Sir John Gurdon, a Cambridge University researcher who has injected human DNA into frogs' eggs, said: "Scientifically... I'm not persuaded it will work. If you put cells from one species into the egg of another, the egg may divide, but you could get a lot of genetic abnormality that won't lead to good-quality stem cells." Links: HFEA Kings College London Newcastle University ......... ZenMaster


For more on stem cells and cloning, go to CellNEWS at http://www.geocities.com/giantfideli/index.html

Sunday, 11 November 2007

UN Analysis on Human Cloning

Ban human reproductive cloning, or prepare for human rights for clones, says UN study. Sunday, 11 November 2007 A report by the United Nations University's Institute of Advanced Studies (UNU-IAS) on the advances on human cloning comes to the conclusion that the international community faces a stark choice: outlaw human reproductive cloning or prepare for the creation of cloned humans. In the second case global leaders need to be prepared to protect the rights of cloned individuals from potential abuse, prejudice and discrimination. The report by the UNU-IAS says a ban on human reproductive cloning, coupled with freedom for nations to permit controlled therapeutic research, is the global community's best option. The report is entitled “Is Human Reproductive Cloning Inevitable: Future Options for UN Governance”. Virtually every nation opposes human reproductive cloning and more than 50 countries have legislated bans on such efforts. However, attempts to reach a binding worldwide treaty failed at the UN in 2005, over divisions on whether to outlaw all cloning or permit cloning of human cells for research. Only a minority of countries supported a non-binding Declaration on Human Cloning to outlaw all types of cloning. At present, another 140 members of the UN have no laws regulating human cloning efforts, therefore providing loopholes for unscrupulous scientists. “Human reproductive cloning could profoundly impact humanity,” says UN Under-Secretary-General Konrad Osterwalder, Rector of UNU. “This report offers a plain language analysis of the opportunities, challenges and options before us – a firm and thoughtful base from which the international community can revisit the issue before science overtakes policy.” Without an international prohibition, human reproductive cloning accomplished in certain countries could be judged perfectly legal by the International Court of Justice, warn UNU-IAS co-authors Brendan Tobin, Chamundeeswari Kuppuswamy, Darryl Macer and Mihaela Serbulea. “Failure to outlaw reproductive cloning means it is just a matter of time until cloned individuals share the planet,” says barrister Mr. Tobin of the Irish Centre for Human Rights, National University of Ireland, at Galway. “If failure to compromise continues, the world community must accept responsibility and ensure that any cloned individual receives full human rights protection. It will also need to embark on an extensive awareness building and sensitivity program to ensure that the wider society treats clones with respect and ensure they are protected against prejudice, abuse or discrimination.” Presently “there is almost universal international consensus on the desirability of banning reproductive cloning based in part on religious and moral grounds, but mostly on concerns about underdeveloped technologies producing clones with serious deformities or degenerative diseases,” Mr. Tobin adds. “The failure to adopt an international convention on therapeutic cloning means that reproductive cloning is inadequately controlled. There are maverick scientists who are continuing with experimentation.” “As technologies advance and possibilities of success increase, the current consensus is likely to erode and with it the possibility of securing a ban on reproductive cloning.” “... but will the world be ready to accept cloned individuals?” “Whichever path the international community chooses it will need to act soon – either to prevent reproductive cloning or to defend the human rights of cloned individuals,” says Dr. A.H. Zakri, Director of UNU-IAS, based in Yokohama, Japan. The report calls the prospect of human cloning “one of the most emotive and divisive issues to face UN negotiators and the international community in recent years.” There have been no substantiated claims of cloned human embryos grown into foetal stages and beyond but such an historic event is not far off, most experts agree. Chamundeeswari Kuppuswamy, one of the co-authors of the report and law lecturer at Sheffield University, said: "China has guidelines on human reproductive cloning but no law as such, while there are many African countries that don't have any legislation in place." "It is not terribly expensive to set up the experiments, process the eggs and get the raw materials needed to perform cloning and as research in the area continues, someone is going to manage it." "The state of the science at the present time, however, means that there are going to be a lot of failures and deformities in any clones produced, which is one of the major concerns if it goes on unregulated." “Licences are being granted for therapeutic cloning, which means in time scientists will perfect the technique for human reproductive cloning.” Cloning have been achieved with many mammals like mice, sheep, pigs, cows, horses and dogs and US researchers last summer accomplished the first cloning of a primate – a rhesus monkey embryo cloned from adult cells and then grown to generate stem cells. Reproductive cloning is, for examples, banned in the UK but scientists are allowed to clone embryos for therapeutic research. Two years ago, a team at Newcastle University managed to create the country's first cloned human embryo, which survived for five days in a laboratory. Prof Alison Murdoch, who led the Newcastle team, said: "We shouldn't be afraid of the idea of having two individuals with genetically identical material, although I cannot see a good clinical need for that." "The risk you run by trying to ban cloning outright is that it may send those scientists who want to do that kind of research to countries where it is completely unregulated." Prof. Ian Wilmut, who led the team that cloned Dolly the sheep, welcomed the UN report, insisting that it would be "dangerous and ethically inappropriate" to clone a child. “By contrast, a method for the production of embryo stem cells would provide important new opportunities to study inherited diseases.” Reference: Is Human Reproductive Cloning Inevitable: Future Options for UN Governance ......... ZenMaster


For more on stem cells and cloning, go to CellNEWS at http://www.geocities.com/giantfideli/index.html

Friday, 19 October 2007

Interspecies Chimeric Mice Using ESCs Created

Scientists create 'interspecies' rodent using embryonic stem cells Friday, 19 October 2007
From left: Mus musculus (house mouse); chimera, a genetic fusion of a house and wood mouse; and Apodemus sylvaticus (wood mouse). Photo courtesy of Bruce Lahn.
By injecting embryonic stem (ES) cells from a wood mouse into the early embryo of a house mouse, an international team of scientists has produced normal healthy animals made up of a mixture of cells from each of the two distantly related species. This is the first time that stem cells from one mammalian species have been shown to contribute extensively to development when introduced into the embryo of another, very different species. In an advanced online posting on Oct. 3, 2007, in the journal Human Molecular Genetics, scientists from the University of Chicago, Sun Yat-sen University, China, and the University of Liverpool, U.K., describe how they produced a viable "chimera" – a single organism with traits from two different species. Although both are rodents, the wood mouse (Apodemus sylvaticus) and the house mouse (Mus musculus) have evolved separately for up to 20 million years. Their genes differ by as much as 18 percent, about 12 times the difference between human and chimpanzee. Before now, scientists have used ES cells to make chimeras within the same species or with closely related species. "There are surprisingly high degrees of conservation in developmental programs between at least some distantly related mammalian species," said study co-author Bruce Lahn, a Howard Hughes investigator and professor of human genetics at Chicago. "When early embryonic cells from two divergent species are mixed together, they can communicate with each other properly and develop into one seamless, functional organism." "These results demonstrate the feasibility of differentiating ES cells into a wide range of cell types in vivo by introducing them into an evolutionary divergent host," the authors wrote. "This interspecies approach may be the only way to study ES cells of some species, such as human ES cells, in an in vivo context." The scientists extracted wood mouse ES cells and introduced a gene that produced a fluorescent protein, which enabled them to visually track the descendents of the stem cells in the chimeric organisms. They then injected about 15 wood mouse ES cells into each of the 1,250 house mouse blastocysts and transferred the viable embryos into 44 surrogate house mouse mothers. From these, 220 pups were born, 16 of them (7.3 percent) showed chimerism based on their appearance. In those 16 chimeras, up to 40 percent of the cells in some organs were wood mouse cells. These cells were integrated into all of the tissues at various levels. The chimeras appeared healthy and had no apparent defects. They did demonstrate some behavioural differences. They were less "jumpy" than a typical wood mouse but more so than a typical, much tamer, house mouse. Although genetically different (the wood mouse has 48 chromosomes, the house mouse, 40), both of these species have similar developmental schedules. The gestation period for a wood mouse is 23 days; the gestation time for a house mouse is 19 days. They also have approximately the same body size. The chimeras varied in terms of how much and where the injected ES cells generated tissue. "It's completely random where the cells will develop and grow tissue," Lahn said, adding that more studies are planned. "We're going to continue with these animals for a while to see if we can understand the developmental cues and learn how to manipulate the system," Lahn said. "For example, could injected wood mouse embryonic stem cells contribute more extensively to the liver in a house mouse that carries a genetic defect that prevents it from growing its own liver? Or, could we alter the stem cells in ways that could prevent them from contributing brain tissue?" The researchers also plan to merge mouse and rat, which have vastly different body sizes, as well as 20 percent genetic difference. Key Scientific and Technological Projects of Guangdong Province and of Guangzhou, and the National Natural Science Foundation of China funded this project. Other authors of the paper are:
Jaehyun Lee, Donghyun Park, Eric Vallender, Tammy Vallender and Li Zhang, of the University of Chicago; Shu-Nong Li, Wei-Qiang Li, Bao-Feng Ma, Tao Wang, Xin-Bing Yu and Xiu-Ming Zhang, of Sun Yat-sen University in Gaungzhou, China; Lahn, Frank Fuxiang Mao and Andy Peng Xiang, affiliated with both institutions; and John Waters of the University of Liverpool, U.K.
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Thursday, 6 September 2007

UK Government Approves Hybrid Embryo Creation

UK Government Approves Hybrid Embryo Creation Thursday, 06 September 2007 The UK government's fertility regulator HFEA yesterday agreed to allow scientists to create human-animal hybrid embryos for stem cell isolation and medical research into debilitating diseases. Dr Lyle Armstrong of Newcastle University's Institute for Human Genetics, who is one of the applicants for this new research, called the decision “excellent news”. "It is a positive outcome, not just for our work but for the progress of British science in general, and we hope that this will lead to new technologies to benefit everyone,” he said. “It does seem a little abhorrent at first analysis, but you have to understand we are using very, very little information from the cow in order to do this reprogramming idea.” “It's not our intention to create any bizarre cow-human hybrid; we want to use those cells to understand how to make human stem cells better.” Another team from King’s College in London has also applied to the HFEA to use hybrid embryos. Dr Stephen Minger, of King's College, said he “applauded” the HFEA for its decision as it was the only ethically justifiable option if scientists were to push forward with their research. It is now expected individual hearings for these two applications will be held in November with other scientists expected to follow suit. HFEA statement on its decision regarding hybrid embryos 5 September 2007 “The decision on how the HFEA should approach the licensing of human-animal hybrids and chimera research has presented a particular challenge as this research is so novel in legal, scientific and ethical terms.” ”In order to ensure that the Authority was able to make an appropriate and reasoned decision, we needed to ensure we had a comprehensive and robust evidence base as a foundation for that decision.” ”Once we had established that such research would legally fall within the HFEA's remit to license, we were then able to start to assess whether such research would, in principle, be necessary and desirable in both scientific and ethical terms. ” ”As such the HFEA, working with support from the Government's Sciencewise programme, put together a detailed and comprehensive consultation gathering evidence from scientists and the wider public about the issues raised by this research. This has been far more than just opinion polling and has involved a series of detailed deliberative sessions where the full range of issues raised by such research were discussed. This enabled participants to make their own informed judgements, asking questions and challenging their own views. ”Having looked at all the evidence the Authority has decided that there is no fundamental reason to prevent cytoplasmic hybrid research. However, public opinion is very finely divided with people generally opposed to this research unless it is tightly regulated and it is likely to lead to scientific or medical advancements. ” ”This is not a total green light for cytoplasmic hybrid research, but recognition that this area of research can, with caution and careful scrutiny, be permitted. Individual research teams should be able to undertake research projects involving the creation of cytoplasmic hybrid embryos if they can demonstrate, to the satisfaction of an HFEA licence committee, that their planned research project is both necessary and desirable. They must also meet the overall standards required by the HFEA for any embryo research. ” ”Having looked at the principles behind this kind of research, an HFEA licence committee will now look at the details of the two specific research applications that were submitted earlier this year. We would hope to have a decision on both applications in November. ” ”In general, people who do not fundamentally oppose embryo research are prepared to accept that human animal research may have some value. But there is a clear demand from people to know more about what researchers are doing and their plans for future work, highlighting a need for better communication about science and research from both the scientific community and ourselves as regulator. In the coming months we will be looking to see how this can be delivered. ” ”In terms of other kinds of hybrid and chimera research, it became very clear that not only did the scientific community not wish to perform such research at present but that the prospect was so distant that they could not envisage what form this research would possibly take in the future. ” ”The Authority felt it would be completely wrong to make a decision on broader hybrid and chimera research without an adequate evidence base. However, the HFEA will continue to monitor the potential for this wider research and any emerging evidence through its 'horizon scanning’ programme.” Links: HFEA ......... ZenMaster


For more on stem cells and cloning, go to CellNEWS at http://www.geocities.com/giantfideli/index.html

Tuesday, 4 September 2007

UK HFEA watchdog should approve 'cybrid' embryos

UK HFEA Watchdog should approve 'cybrid' embryos Tuesday, 04 September 2007 The creation of embryos that are part-human and part-animal should be approved by the Government’s fertility watchdog on Wednesday, after a consultation revealed strong scientific support for the work and only limited public concern. The Human Fertilisation and Embryology Authority (HFEA) is expected to agree in principle that scientists can use interspecies embryos that are 99.9 per cent genetically human to investigate diseases such as Parkinson’s and diabetes. A decision to allow cytoplasmic hybrid or “cybrid” embryos, formed by placing human DNA into an empty animal egg, is anticipated after the four-month consultation found that most opposition to the experiments comes from people who object to all embryo research. The wider public, by contrast, was broadly supportive: a poll found that 61 per cent agreed with such work if it might improve understanding of diseases. Scientists also backed the research overwhelmingly. A positive ruling would clear the way for the authority to consider licence applications from research teams at King’s College, London and the University of Newcastle-upon-Tyne, who want to produce cybrids to create stem cell models of disease. See also: UK Government Approves Hybrid Embryo Research ......... ZenMaster


For more on stem cells and cloning, go to CellNEWS at http://www.geocities.com/giantfideli/index.html

Sunday, 26 August 2007

British scientists in hybrid embryo plea

British scientists in hybrid embryo plea Sunday, 26 August 2007 Last year, British scientists applied for licence to create human-cow hybrid embryos, to isolate stem cells from the resulting blastocysts. Now, the Human Fertilisation and Embryology Authority is expected to announce its decision next week on whether to give permission to the UK laboratories to create the hybrid embryos to advance the understanding of genetic diseases. Dr Stephen Minger from King's College London is one of the researchers that has applied for a licence to do work using such hybrids. Another is Dr Lyle Armstrong, who is based at the North East England Stem Cell Institute (NESCI ) at the International Centre for Life in Newcastle. Dr. Minger said in an interview with The Observer, that: “I'm cautiously optimistic that the authority will allow us a licence. I hope we have made the case that by doing this research; we can study a number of genetic diseases far more clearly. The cell discoveries we make could then be used to develop therapies for diseases such as Alzheimer's which affect so many people, but for which we now have almost no therapy to offer.” To do this work they would need a large number of embryos to make stem cells, far more than could be achieved by asking women to donate their eggs for research. Instead of using human eggs and sperm for these experiments, Dr. Minger thinks it makes far more sense to use cow eggs, since these can be taken from ovaries of thousands of cows that are slaughtered every day anyway. To do this work they would need a large number of embryos to make stem cells, far more than could be achieved by asking women to donate their eggs for research. The British government this spring shifted its position on animal-human hybrid embryos: having been initially against the concept, it is now proposing to allow partial hybrids, where a complete set of human genes is inserted into an animal's egg cell, for research purposes only, through a new Human Tissue and Embryo Bill aimed at overhauling the laws surrounding fertility treatment. The move has prompted strong protests from some religious and anti-abortion groups that oppose any such research. ......... ZenMaster


For more on stem cells and cloning, go to CellNEWS at http://www.geocities.com/giantfideli/index.html

Wednesday, 1 August 2007

Leave UK hybrid embryo decisions to experts

Leave UK hybrid embryo decisions to experts, panel says August 1, 2007

Experts, not government ministers, should decide what kind of hybrid animal-human embryo experiments to allow in Britain, a parliamentary panel said in a report issued on Wednesday.

Parliamentarian Phil Willis, who led the committee, said the government should leave the decision to regulators with the expertise to weigh potential scientific benefits.

"On the question of research using inter-species embryos, the committee is quite clear that it wishes to see a greater role for the regulator within a broad permissive framework set out by Parliament," Willis told a news conference before the release of the report. ..........

What do you think? Is it good or bad to keep politicians out of scientific decisions? .........

ZenMaster


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CellNEWS at http://www.geocities.com/giantfideli/index.html

Sunday, 29 July 2007

Would you like a pig’s heart?

Is it right to clone animals for human transplants? July 29, 2007 Several research groups, and companies, are trying to make transgenic and cloned pigs to alleviate the organ donor shortage. Opponents have said that it raises serious ethical issues over the use of animals and poses a major safety question for humans. Do you think this marks a scientific breakthrough in cloning and availability of organs for transplants? Or does it raise concerns over the methods being used in cloning technology? Could you think of receiving a pig organ or tissue yourself, if needed? Pigs are very suitable for many reasons, they haven’t been chosen without thought: they are about the same size (body weight) as we are, they have a very similar internal anatomy as we, they grown fast (full size within a year) and are genetically well characterised. Several research groups, and now companies, are trying to make transgenic pigs for many years now, which would lack one of the major immunological obstacles to this xenotransplantation (transplanting organs between different animals and humans). It’s a simple sugar molecule on the surface of pig cells that now has been removed in these new breeds, and before was known to be the major immunological reactant in humans transplanted with pig tissues. The animals lack the gene responsible for "alpha-1,3-galactosyltransferase" (GT) — an enzyme normally present in the pig vascular system. Humans have natural, preformed antibodies to GT, resulting in immediate (acute) rejection of any pig-to-human transplant. The fact that these genetically engineered "GT-knockout" pigs lack GT removes one obstacle to cross-species transplantation, or xenotransplantation, between pigs and humans. Apart from the possible transplantation of organs such as the kidney or heart, pigs are also viewed as a potentially invaluable source of islet cells — the insulin-producing cells of the pancreas — for use in transplantation as a treatment for type-1 diabetes. Preliminary studies have reported encouraging results with transplantation of organs from GT-KO pigs into nonhuman primates. Hearts transplanted from GT-KO pigs into baboons have survived for several months, without the need for intensive drug treatment to suppress the recipient animal's immune system. However, many obstacles remain to be overcome before exploratory studies of xenotransplantation from GT-KO pigs to humans can begin. The transplanted hearts do not show the pattern of acute, overwhelming rejection typical of cross-species transplantation. However, there is evidence of another type of rejection, characterized by blood clots developing in the small blood vessels. This suggests a possible "coagulation dysregulation" between pigs and primates. New approaches will be needed to address the problem: either improved approaches to immunosuppressant drug therapy or further genetic manipulation of the donor animals. A lot is also known about pig’s physiology during medical procedure’s which make them suitable for this kind of treatment. Do you know that live sedated pigs are used for many training purposes for catastrophe medicine (surgeons who need training on complex wounds) and military doctors (shot gun and shell wounds)! Some argue these issues can be very emotional and scary for many people. True, but that’s exactly why they need to be discussed, to take away the scary part. It is usually when you don’t know, or don’t talk about something straight out, it becomes more and more scary. When you get to know the details and ventilating your anxiety it usually becomes easier to live with. Some people ask “Why spend so much money and effort on this?” This kind of work to develop donor organs from pigs, is not particular expensive compared to other things our societies put money on. And in the long run there will be a lot of savings instead, when people can live a healthy life instead. And they are definitely not impractical experiments. If you think so, you have not understood the slightest of what can be done to help people. ......... ZenMaster


For more on stem cells and cloning, go to CellNEWS at http://www.geocities.com/giantfideli/index.html

Friday, 29 June 2007

New Regulations Needed For Xenotransplantations

New Regulations Needed For Patients Receiving Animal Tissue Donation June 29, 2007 A new article in the Journal of Law, Medicine and Ethics calls for a change in the regulations surrounding xenotransplantation, the transplanting of animal cells, tissues or organs into humans. Although few xenotransplantation procedures have been done to this time, there appears to be a lack of awareness among potential xenotransplant patients about the risk of the procedures, and the required lifetime of infectious disease monitoring that come with it. ......... ZenMaster


For more on stem cells and cloning, go to CellNEWS at http://www.geocities.com/giantfideli/index.html

Thursday, 26 April 2007

EU lawmakers back rules for stem cells

EU lawmakers back rules for stem cells and other cures Reuters - Wed Apr 25, 2007 European lawmakers backed new rules for stem cell and other advanced medical therapies on Wednesday, despite opposition from a key member of the European Parliament.The European Union legislature rejected so-called ethical amendments to the regulation that will create a centralized process for approving new tissue and cell engineering therapies. ................. Some background: Embryo-cell vote spotlights MEPs' ethics EU parliament set for clash over stem cell research MEP defends stance on EU gene therapy rule ................. ZenMaster


For more on stem cells and cloning, go to CellNEWS at http://www.geocities.com/giantfideli/index.html

Friday, 6 April 2007

Britain urged not to ban hybrid embryo research

Britain urged not to ban hybrid embryo research Reuters - Wed Apr 4, 7:03 PM ET Scientists and lawmakers urged Britain on Thursday to scrap a proposed ban on creating hybrid animal-human embryos for research into illnesses such as Parkinson's, stroke and Alzheimer's. In December, the British government proposed a ban on the creation of hybrid embryos due to what it called "considerable public unease," but the Commons Science and Technology Committee said a ban was unacceptable and could harm British science. ......... ZenMaster