Tag: transplantation

Bioethics Blogs

Do Extended Pluripotent Stem Cells Raise Ethical Issues?

On April 6, the journal Cell published work (subscription or online article purchase required) from the Salk Institute in San Diego, in which scientists have created a new “reprogrammed” stem cell.

These cells are called “extended pluripotent stem cells” or “EPS” cells.  They are different from embryonic stem (ES) cells, which are removed from intact embryos that arise from fertilization—typically requiring specific creation and destruction of an embryo.   Of course, ES cells can be human or non-human, depending on the source.

EPS cells are similar to “induced pluripotent stem cells,” or iPSCs, invented in 2006.  The latter are generated from adult skin cells that have been reprogrammed, using genetic alterations.

EPS cells may be made by reprogramming ES cells or skin cells or, if I understand the work correctly, iPSCs.  In this case, the reprogramming is done with a cocktail of chemicals in the lab.

But EPS cells are more capable than iPSCs.  Unlike iPSCs, which can give rise to many different types of cells but not all—including not a placenta and not an entire intact new individual—EPS cells can do all of that.  They are totipotent, meaning they can make all the cells of an individual from their species.  Moreover, they are quite long-lived in the laboratory.  EPS cells from one species—e.g., humans—can be placed into non-human (e.g., mouse) embryos to make hybrid animals that, it appears, survive quite well and can breed.  And, remarkably, the authors of the Cell paper report (again, if I understand correctly, and I think I do) that they were able to use a mouse EPS cell to give rise to a whole new mouse, not “just” a laboratory tissue hybrid.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

Bioethics Blogs

Teaching Medical Anthropology by Ari Gandsman

In the decade since becoming a full time professor, medical anthropology has been one of my core courses. I have taught it seven times.  Although the basic structure of the course remains similar, emphases have shifted over time. Perhaps I can best highlight the evolution of the course through a discussion of readings I use since readings are the backbone of a syllabus.  Even though I generally do not follow texts closely since I see lectures as overlapping but also supplemental and complimentary to readings, I try to mirror topics that they will be reading about, often highlighting a general theoretical literature or approach while the students read a single illustration.

Starting from the beginning, my history of medical anthropology remains the same, focusing on when “medicine” was subsumed into broad and now antiquated anthropological categories of magic and witchcraft. I never stray far from Evans-Pritchard’s Witchcraft, Oracles & Magic Among The Azande, an apparent professional contractual obligation for meAlthough I have given them the entire ethnography [the abridged in print edition] to read twice in the past, I have more lately just given them a short excerpt, often “The Notion of Witchcraft Explains Unfortunate Events.” I once also used W.H. Rivers Medicine, Magic and Religion but, although fascinating and of historic importance, it proved esoteric for an undergraduate course.  When I first started teaching, I tried to include more on non-Western medical systems, including using ethnographies on Traditional Chinese Medicine or Tibetan medicine. More recent students may be disappointed that I do not delve further into non-Western medical systems, what many students with hazy ideas of the discipline may think a medical anthropology course should almost entirely consist of.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

Bioethics News

Patient’s own menstrual blood stem cells used to treat Asherman’s syndrome

Infertility treatment.”The best option for endometrial regeneration in patients with Asherman’s syndrome.”

Asherman’s syndrome is an acquired uterine abnormality characterised by the presence of intrauterine adhesions, and which clinically causes infertility, recurrent miscarriages and menstrual changes. Its prevalence ranges between 2% and 22% of infertile women.

Several surgical and medical treatments have been proposed, but outcomes have been unsatisfactory. Now, a study published in Human Reproduction has proposed treating the condition with adult stem cells obtained from the patient’s own menstrual blood.

To date, seven infertile women with Asherman’s syndrome have been treated. All patients were of reproductive age (33.7 ± 1.5 years) and had suffered infertility for 4.8 ± 1.2 years.

Menstrual blood stem cells. The blood stem cells obtained on day 2 of menstruation were transplanted to the uterus, followed by hormone stimulation.

Another successful cell therapy with no ethical difficulties

Endometrial thickening and return to its normal morphology were observed in all patients. One patient became pregnant spontaneously; four others underwent embryo transfer and two of these became pregnant.

The findings of this study suggest that transplantation of adult stem cells obtained from the patient’s own menstrual blood may be one of the best options for endometrial regeneration in patients with Asherman’s syndrome.

This practice — from a bioethical point of view — merits a favourable assessment, since adult stem cells are used which, as we know, present no ethical difficulties for use.

La entrada Patient’s own menstrual blood stem cells used to treat Asherman’s syndrome aparece primero en Bioethics Observatory.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

Bioethics News

New advances and challenges in the production of human-animal chimeras

They had overcome the obstacle of using human embryonic stem cells, but that even so, a ethical difficulty remained with the producing organs formed almost entirely of human cells in experimental animals.

It seems a little excessive that, in less than two months, we have dedicated three reports to the latest studies by Juan Carlos Izpisúa and his group. Nonetheless, we believe that the importance of his work merits this level of interest.

In our first report, we referred to a study published in Nature, which describes — among other breakthroughs — the production of human-animal chimeras in order to generate quasi-human organs for use in transplantation. In the report, we mentioned the ethical difficulties evident in the study as a result of the use of human embryonic stem cells.

In the second, we discussed the new steps taken in the production of human organs in animals, in connection with an interview by Izpisúa published in Investigación y Ciencia (the Spanish version of Scientific American). In the interview, Izpisúa particularly stressed that, from an ethical point of view, they had overcome the obstacle of using human embryonic stem cells, but that even so, a potential ethical difficulty remained with the possibility of producing organs formed almost entirely of human cells in experimental animals.

Now, we evaluate these experiments by analysing the latest findings published in an article in scientific journal Cell (see HERE).  We also discuss another paper by a different research group, in which the authors also describe the production of human-animal chimeras, likewise with the intention of producing organs for transplantation.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

Bioethics Blogs

Regenerative Medicine: The Promise and Peril

Caption: Scanning electron micrograph of iPSC-derived retinal pigment epithelial cells growing on a nanofiber scaffold (blue).
Credit: Sheldon Miller, Arvydas Maminishkis, Robert Fariss, and Kapil Bharti, National Eye Institute/NIH

Stem cells derived from a person’s own body have the potential to replace tissue damaged by a wide array of diseases. Now, two reports published in the New England Journal of Medicine highlight the promise—and the peril—of this rapidly advancing area of regenerative medicine. Both groups took aim at the same disorder: age-related macular degeneration (AMD), a common, progressive form of vision loss. Unfortunately for several patients, the results couldn’t have been more different.

In the first case, researchers in Japan took cells from the skin of a female volunteer with AMD and used them to create induced pluripotent stem cells (iPSCs) in the lab. Those iPSCs were coaxed into differentiating into cells that closely resemble those found near the macula, a tiny area in the center of the eye’s retina that is damaged in AMD. The lab-grown tissue, made of retinal pigment epithelial cells, was then transplanted into one of the woman’s eyes. While there was hope that there might be actual visual improvement, the main goal of this first in human clinical research project was to assess safety. The patient’s vision remained stable in the treated eye, no adverse events occurred, and the transplanted cells remained viable for more than a year.

Exciting stuff, but, as the second report shows, it is imperative that all human tests of regenerative approaches be designed and carried out with the utmost care and scientific rigor.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

Bioethics News

The Future of Bioethics: Organ Transplantation, Genetic Testing, and Euthanasia

By Ana Lita

When you think of bioethics, some of the first hot-button topics you may consider are organ transplantation, fertility and genetic engineering, and end-of-life-care. The Global Bioethics Initiative serves as a platform to address many bioethical questions and engages in public debates to develop resolutions to present and emerging issues.

Dr. Ana Lita, founder of the Global Bioethics Initiative, discusses the various areas GBI addresses and highlights the organization’s contributors in their prospective fields. She acknowledges the valuable contribution of the current president of GBI, Dr. Bruce Gelb, in the field of organ transplantation. She also addresses the original co-founder of GBI, Dr. Charles Debrovner, and his lifelong passion in the field of fertility and genetic engineering. Lastly, Dr. Lita offers a brief insight into the future of Bioethics in these uncertain times.

ORGAN MARKETS AND THE ETHICS OF TRANSPLANTATION 

Recent developments in immunosuppressive drugs and improved surgical techniques have now made it much easier to successfully transplant organs from one human body to another. Unfortunately, these developments have led to the rise of black-markets in human organs. This underground market is where people who need kidneys to survive or to improve the quality of their lives, for example, purchasing such organs from impoverished persons in the developing world. In January 2017, scientists announced that they successfully created the first human-pig hybrid and a pig embryo with some human characteristics. Given the increasing need for transplant organs, should such markets be regulated and legalized?  Could the success of therapeutic cloning eliminate the need to consider this option?

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

Bioethics Blogs

The Semantics of Therapy, Part II

A previous blog post of “The Semantics of Therapy” posed three questions about the human genome being a “patient” to be treated. One reader found the post “provocative and disturbing” and called for further explanation and discussion of the questions posed. That will take some time and several postings.

The first of the questions to be considered is this: If the “patient” is a genome, to whom does the researcher answer?   An answer from recent history may shed some light on this important issue.

33 infertile couples underwent a novel procedure at New Jersey’s Saint Barnabas Medical Center during the years 1996-2001. Embryologist Jacques Cohen used cytoplasmic transfer–ooplasm from the oocytes of fertile women was transferred into the eggs of infertile women–in the hope of establishing pregnancies in the latter. The outcome was 13 pregnancies and 17 babies from the Saint Barnabas experience (see accounts here and here).

According to a 2014 BBC article, one resulting pregnancy, which ended in miscarriage, revealed a missing X chromosome in the fetus. The same anomaly was noted in another child: one of a set of twins from a different pregnancy. Later, one child showed evidence of developmental delay. In 2014, Cohen estimated that the worldwide experience of cytoplasmic transfer between oocytes had resulted in the births of 30-50 babies, although the FDA had effectively stopped the procedure in the U.S. in 2002.

What had the follow-up on the babies born through cytoplasmic transfer been in 2014?

Due to a lack of funding, Cohen says, it hasn’t been possible to find out about how any of the children like Alana who were born from cytoplasmic transfer are doing.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

Bioethics Blogs

Equipoise and Caution Regarding “Ethical” Stem-Cell Therapy

You may have seen one of the many news reports this week about an “adult” stem cell treatment gone bad.  In it, doctors, not working in regulated industry or in the bounds of a clinical trial, injected stem cells derived from a person’s fatty tissue into the eyeballs of three people in an attempt to treat a vision-destroying condition called macular degeneration—and all three lost what remaining vision they had.  T

In a separate experience, two people received “reprogrammed” stem cells, also called “induced pleuripotent stem cells” or “iPSCs,” for the same condition, and they did not appear harmed, and may have been showing early signs of improvement, one year later.  In this second case, the cells are described as having undergone rigorous quality testing before being injected into the patients’ eyeballs.

The two cases are described in this week’s New England Journal of Medicine.  The links above are to those reports; subscription may be required to read them.  NEJM makes some of its editorials and perspective pieces generally available, other articles not.  Two such articles, one from FDA and one from a physician at Boston Childrens’ Hospital, address these cases.  In both opinion articles, the authors argue that careful regulation and quality control of stem cell studies is critical to their ethical testing.

To say this position is hard to argue with is a gross understatement.  I will confess that on this blog, in the past, I have wondered whether some use of “adult” or “somatic” stem cells is over-regulated, as, for example, when such cells are obtained from a woman’s fatty tissue, and reinjected into her in an attempt at breast reconstruction after surgery.  I’ve seen proposals in the past for work like that, and it seemed pretty straightforward—recovering a cell layer from a centrifuge, and reinjecting, all under sterile conditions.  The doctors in question in the case I saw were not in any way trying to cut any corners.  But existing regulation would have prevented their proposed breast-surgery work without a couple million dollars’ worth of the kind of work needed, and usually funded by industry, before commencing human trials of a new treatment.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

Bioethics Blogs

ORGAN DONATION AFTER MEDICAL AID IN DYING

Jennifer A. Chandler describes some of the ethical and legal challenges surrounding organ donation following medical assistance in dying.

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Today, it is medically possible to donate organs following death brought about by medical assistance in dying. This currently happens in countries like Belgium and the Netherlands. People with neurodegenerative conditions like amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig’s disease, or multiple sclerosis (MS) are eligible to donate organs. Those with cancer, however, are not eligible because of risks to recipients.

In Canada, people with neurodegenerative conditions who satisfy the legal eligibility criteria for assisted dying may also meet the medical eligibility criteria for organ donation. However, this possibility raises novel ethical, legal, and policy issues that must be carefully considered. The following four hypothetical cases illustrate some of these issues.

CASE 1 – A patient seeks assisted dying and wants to donate to a family member.

Some provinces allow people to direct their organ donations to relatives after they die. Some patients who choose assisted dying may derive some comfort from being able to help a family member in this way. There is the risk, however, that patients may feel pressured to seek assisted dying, in part, to benefit a sick relative.

CASE 2 – A family member is asked to consent to cornea donation for a loved one who passed away through assisted dying. The patient was not asked about this before his death because he was not registered as an organ donor, and nobody wanted to burden him with the decision. 

It seems inappropriate not to ask patients about organ donation prior to death, when they are capable of speaking for themselves.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

Bioethics News

Thomas Starzl, Trailblazer in Organ Transplantation, Dies at 90

March 7, 2017

(NPR) – Thomas Starzl, the doctor who pioneered liver transplant surgery, has died at the age of 90. In an announcement on its website, the University of Pittsburgh Medical Center said Starzl died peacefully at his home on Saturday. “His work in neuroscience, metabolism, transplantation and immunology has brought life and hope to countless patients, and his teaching in these areas has spread that capacity for good to countless practitioners and researchers everywhere,” his family wrote in a statement issued Sunday by UPMC and the University of Pittsburgh.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.