Tag: cells

Bioethics News

A Lesson From the Henrietta Lacks Story: Science Needs Your Cells

It’s often portrayed as a story of exploitation. Henrietta Lacks, a poor, young African-American woman, learned she had terminal cancer. Cells collected from a biopsy of her cancer were cultured without her knowledge or permission to develop a cell line, called HeLa. Over the ensuing decades, research using HeLa cells led to scores of medical advances, saving lives — and making a lot of money for a lot of people, though not for Ms. Lacks’s family

Source: Bioethics Bulletin by the Berman Institute of Bioethics.

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

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

Creative Minds: Preparing for Future Pandemics

Jonathan Abraham / Credit: ChieYu Lin

Growing up in Queens, NY, Jonathan Abraham developed a love for books and an interest in infectious diseases. One day Abraham got his hands on a copy of Laurie Garrett’s The Coming Plague, a 1990s bestseller warning of future global pandemics, and he sensed his life’s calling. He would help people around the world survive deadly viral outbreaks, particularly from Ebola, Marburg, and other really bad bugs that cause deadly hemorrhagic fevers.

Abraham, now a physician-scientist at Brigham and Women’s Hospital, Boston, continues to chase that dream. With support from an NIH Director’s 2016 Early Independence Award, Abraham has set out to help design the next generation of treatments to enable more people to survive future outbreaks of viral hemorrhagic fever. His research strategy: find antibodies in the blood of known survivors that helped them overcome their infections. With further study, he hopes to develop purified forms of the antibodies as potentially life-saving treatments for people whose own immune systems may not make them in time. This therapeutic strategy is called passive immunity.

Already, Abraham has begun collecting blood samples from survivors of Ebola, Marburg, and other hemorrhagic fevers. The next step—and it can be a long and tedious one—is to isolate the B immune cells that produce the antibodies responsible for fighting each of the viruses. When he finds one, Abraham will then identify and sequence the specific immunoglobulin genes encoding those antibodies in the appropriate B cell.

Having those DNA sequences in hand, Abraham can make large quantities of the antibodies, allowing him to study their ability to neutralize the viruses in lab dishes and infected animals.

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

New Section: Law & Bioethics

New Section: Law & Bioethics — Voices in Bioethics

New Section: Law & Bioethics

Apr 19

Apr 19 New Section: Law & Bioethics

Politicize my Bioethics: Compensation for egg cells

Nov 11 Politicize my Bioethics: Compensation for egg cells

Call For Stories

Mar 23 Call For Stories

Source: Voices in Bioethics, opinions, scholarship, and news from the world of bioethics.

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

An Assessment of Mitochondrial Replacement Therapy

By: Alexa Woodward

Last year, a baby boy was born from an embryo that underwent mitochondrial replacement therapy (MRT). MRT was used to prevent this child from inheriting a mitochondrial disease from his mother, specifically infantile subacute necrotizing encephalomyelopathy – a disease that affects the central nervous system and usually results in death within the first few years of life. While controversial, assisted reproductive technologies (ARTs) such as MRT provide prospective parents with additional options and have the potential to improve the quality of human life by preventing disease.

This story is of bioethical interest because this technique results in germline modification, which is the alteration of DNA in the reproductive cells of humans that will be passed on to their offspring. Implementing MRT in humans has consequentially garnered much criticism, from simple health-related implications (such as unknown harms to potential offspring and eugenics concerns) to the futuristic next logical step of scientific intervention; directly editing the nuclear genome.

With MRT, modifications affect the mitochondrial genome (mtDNA), not the nuclear genome. Researchers emphasize the lack of bearing that mtDNA has on personal characteristics and the overall maintenance of “genetic integrity,” especially when compared to using the whole donor egg with an “unrelated” nuclear genome.1 Even so, additional concerns arise regarding the long-term anthropological effects, blurring the distinction between therapy and enhancement, and issues of resource allocation.

Mutations and deletions  in the mitochondrial genome can result in mitochondrial diseases affecting the neurological, musculoskeletal, cardiac, gastrointestinal, renal, and other systems, all of which are incurable.  MRT uses the intended parents’ nuclear DNA in conjunction with a donor’s mitochondria.

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

Breakthrough Immunotherapies Seem Like a Dream Come True for Children with Leukemia

Guest Post: Nancy Jecker, Aaron Wightman, Abby Rosenberg, Doug Diekema

Paper: From protection to entitlement: selecting research subjects for early phase clinical trials involving breakthrough therapies

A breakthrough therapy to cure cancer in children suffering from acute lymphoblastic leukemia (ALL) is a dream for many families.  New immunotherapies appear to make this dream a reality. Such therapies use a person’s own immune cells to recognize and combat their disease. In the largest study to date of ALL patients treated with a form of immunotherapy known as Chimeric Antigen Receptor (CAR) T-Cell therapy, a 93% remission rate was reported. Such results are a glimmer of hope for those whose prognoses were previously considered very poor.

However, the good news is tempered by the fact this potentially lifesaving experimental therapy may not be available to everyone who might benefit. And demand is growing as word spreads. Since CAR T-cell therapy for ALL is available only through clinical trials, do patients have a right to participate? How should we choose among medically suitable candidates?

We have faced these questions before. Most recently, with ZMapp to treat Ebola Virus Disease, azidothymidine (AZT) to treat HIV and AIDS, and Immunitab (Gleevac) to treat Chronic Myleogenous Leukemia. Are patients suffering from devastating, life-threatening diseases entitled to breakthrough therapies?

In a recent paper, we argue that benefit is a continuum, from the complete uncertainty associated with standard research, to an intermediate stage where evidence of benefit mounts and reaches a peak, to a final stage of clearly demonstrated benefit that is sufficient to gain approval for clinical applications.

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

Blinded by the Promise of Stem Cell Treatments

Alan F. Cruess cautions against the use of unproven stem cell ‘treatments.’

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Recently, many of you may have read about three patients who are blind after receiving stem cell ‘treatments.’  The patients were ‘treated’ at a Florida clinic for age-related macular degeneration. This common eye condition is the leading cause of vision loss among people over the age of 50. The clinic harvested stem cells from the patients using liposuction and then injected these stem cells into their eyes. Again, these three patients, are now all blind as a result of this unproven ‘treatment.’

There are two types of age-related macular degeneration: ‘wet’ and ‘dry.’ In recent years, treatment of wet macular degeneration has been transformed by new drugs which can be very effective if they are applied early. Meanwhile, treatment of the more common dry macular degeneration remains elusive. As such, patients with dry macular degeneration may be desperate to prevent and reverse blindness and willing to try emerging regenerative therapies.

Some experimental stem cells treatments to prevent blindness are promising, and they are being studied worldwide in laboratories and highly regulated clinical trial settings. In these settings, the safety and efficacy of experimental treatments can be closely monitored. Yet, the safety and efficacy should be called into question when these so-called ‘treatments’ are marketed outside of the research context. This was the case at the Florida clinic.

Before subjecting oneself or a loved one to any new ‘treatment’ with stem cells patients should be informed about the risks and potential benefits of the proposed 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

Snapshots of Life: Healing Spinal Cord Injuries

Caption: Mark McClendon, Zaida Alvarez Pinto, Samuel I. Stupp, Northwestern University, Evanston, IL

When someone suffers a fully severed spinal cord, it’s considered highly unlikely the injury will heal on its own. That’s because the spinal cord’s neural tissue is notorious for its inability to bridge large gaps and reconnect in ways that restore vital functions. But the image above is a hopeful sight that one day that could change.

Here, a mouse neural stem cell  (blue and green) sits in a lab dish, atop a special gel containing a mat of synthetic nanofibers (purple). The cell is growing and sending out spindly appendages, called axons (green), in an attempt to re-establish connections with other nearby nerve cells.

So, what spurred this particular neural stem cell to reactivate itself? The secret lies in the nanofiber gel. It’s been specially engineered to mimic the structure within a healthy spinal cord, as well as seeded with biochemical signals that naturally prompt the cell to grow and start forming connections.

The image—a winner in the Federation of American Societies for Experimental Biology’s 2016 BioArt competition—was taken by Mark McClendon and Zaida Alvarez Pinto, researchers in the lab of Samuel Stupp at Northwestern University, Evanston, IL. They used a scanning electron microscope to capture the image and then colorized the neural stem cell and nanofibers to make it a work of art.

McClendon and Alvarez Pinto hope that this gel, along with other bioengineered materials under development in the Stupp lab, might one day be used to prevent or reverse loss of function in people who suffer severe spinal cord or other nerve injuries.

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 situation of the clinical use of stem cells

In January 2017, an article was published in JAMA (The Promise of Palliative Care – Translating Clinical Trials to Clinical Care) which, in our opinion, summarises the situation of the clinical use of stem cells extremely well.

It begins by referring to the possible sources of stem cells: embryonic, adult and induced, the latter known as iPS cells.

Stem cells clinical use

It continues by saying that stem cells have many clinical applications, especially stem cells from bone marrow; these are used particularly in haematological diseases, but also in bone fractures, retinal diseases, spinal cord injuries, Parkinson’s and Huntington’s disease, and in myocardial infarction, although many of these treatments are still in the experimental phase.

While stem cells might sooner or later help to treat many patients, they can also have negative side effects if not used correctly, as these cells can emigrate to other parts of the body and create problems, as well as causing tumors.

Finally, the authors refer to the proliferation of clinics offering stem cell treatments, warning that many of these do not meet the necessary quality requirements, since they are not supervised by the health control agencies of the different countries and, as such, they offer the possibility of remarkable cures that are not yet medically proven. Cosmetic treatments and treatments for arthritis and autism are particularly sought after.

See our Special Report about this matter.

La entrada The situation of the clinical use of stem cells aparece primero en Bioethics Observatory.

Source: 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 Blogs

Fighting Parasitic Infections: Promise in Cyclic Peptides

Caption: Cyclic peptide (middle) binds to iPGM (blue).
Credit: National Center for Advancing Translational Sciences, NIH

When you think of the causes of infectious diseases, what first comes to mind are probably viruses and bacteria. But parasites are another important source of devastating infection, especially in the developing world. Now, NIH researchers and their collaborators have discovered a new kind of treatment that holds promise for fighting parasitic roundworms. A bonus of this result is that this same treatment might work also for certain deadly kinds of bacteria.

The researchers identified the potential new  therapeutic after testing more than a trillion small protein fragments, called cyclic peptides, to find one that could disable a vital enzyme in the disease-causing organisms, but leave similar enzymes in humans unscathed. Not only does this discovery raise hope for better treatments for many parasitic and bacterial diseases, it highlights the value of screening peptides in the search for ways to treat conditions that do not respond well—or have stopped responding—to more traditional chemical drug compounds.

Humans, parasites, and bacteria depend on the same cellular pathway to break down glucose for energy. This life-sustaining metabolic pathway includes essentially all of the same enzymes with one notable exception: cofactor-independent phosphoglycerate mutase (iPGM). This enzyme is found in parasites and bacteria, but not in people. Yes, we humans have an enzyme that does that same job—but it does so in a different way and is assembled from an entirely different sequence of amino acid building blocks.

Given this very exploitable difference, iPGM jumped several years ago to the top of the list as a drug target that would kill disease-causing parasites without harming people.

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.