Tag: cells

Bioethics Blogs

The Very Early Embryo & Its Moral Signifiance

by Andrew J. Prunty

As technology and biological research continue to develop in the twenty-first century, it is necessary to address and further define the ethical considerations of embryonic research and the appropriate rights that may limit the extent of human research on zygotes, blastocysts, and fetal scientific advancement. Because the area of harvesting embryonic stem cells remains significantly undefined, both legally and morally, there are vastly different opinions between researchers and bioethicists, mainly because of ethical limitations, on the rights that should be granted to cells with the potential to develop into human beings and the consequences of neglecting significant scientific research or advancement.

Current laws in the United States differ at the federal and state level, but there is no consistency in recognizing human embryos as humans, or affording them the same legal rights granted to a child; in fact, legal precedent actually detracts certain rights from developing embryos, favoring a human’s ability to destroy a potential human being (i.e. Roe v. Wade[i]) or the categorization of embryos as property (i.e. Davis v. Davis[ii], A.Z. v. B.Z.[iii], Marriage of Dahl[iv], or Reber v. Reiss[v]). These case law samples suggest the courts’ inability to reach a conclusion as to what is the status of an embryo.

The debate is not only circumscribed to matters of research, but to fundamental controversial and intertwined issues of bioethics such as: when life begins, embryonic stem cells, fetal rights, abortion, et cetera. All these topics are contentious and when one topic arises, they begin to comingle.

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 Ethics of In Vitro Gametogenesis

Françoise Baylis comments on the ethics of using gametes derived from human induced pluripotent stem cells for future human reproduction.

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A recent New York Times article, provocatively titled “Babies from Skin Cells? Prospect is Unsettling to Some Experts,” has once again drawn attention to controversial research by scientists at Kyushu University in Japan who succeeded in making fertile mouse pups using eggs created through in vitro gametogenesis (IVG). This is a reproductive technology that involves creating functional gametes (sperm and eggs) from induced pluripotent stem cells. Induced pluripotent stem cells are cells derived from adult body cells (such as skin cells) that have the ability to become other body cells including reproductive cells (sperm and eggs).

Supporters of this reproductive technology eagerly anticipate similar research in humans. Indeed, enthusiasts are quick to trumpet the potential benefits of in vitro gametogenesis. These benefits fall into three general categories.

First, we are told that research to derive human gametes from induced pluripotent stem cells is important for basic science. It will advance our understanding of gamete formation, human development, and genetic disease. In turn, this increased understanding will create new options for regenerative medicine.

Second, we are told that this research will allow clinicians to improve fertility services. For example, with in vitro fertilization (IVF), women typically have to undergo hormonal stimulation and egg retrieval. This can be onerous in terms of the time required for interviews, counseling, and medical procedures. It can also be harmful. Potential psychological harms include significant stress and its sequelae.

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

Babies From Skin Cells?

Prospect is unsettling to some experts. Nearly 40 years after the world was jolted by the birth of the first test-tube baby, a new revolution in reproductive technology is on the horizon — and it promises to be far more controversial than in vitro fertilization ever was

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 News

Stem cell research. The two sides of the coin

Science facing market

The “heads” of stem cell research

Stem cells today represent a great hope for the future of regenerative medicine due to their ability to differentiate into cell lines of almost any tissue, making them a promising therapeutic option for many diseases.

These pluripotent cells are found in embryonic and also in adult tissues. Their isolation and culture in specific media may lead to the development of tissues that are useful in regenerative therapies for conditions such as heart disease, myelopathies, diabetes, nerve injuries, retinopathies, etc. After their isolation, they are injected directly into the tissues to be regenerated, so that the stem cells differentiate into cells of these same tissues.

A third way of obtaining pluripotent cells is that described by Yamanaka 10 years ago, a finding for which he was awarded the Nobel prize in Medicine. Starting from a differentiated adult cell, Yamanaka managed to find a way of “dedifferentiating” it so that it returned to its pluripotent state, to then “redifferentiate” it into a particular cell line with therapeutic utility. These are known as iPS or induced pluripotent stem cells.

Similarly, tissues that simulate the function of certain organs have been reproduced in vitro from stem cells, and could, in the future, be an alternative to current organ transplantation.

The current state of the clinical application of stem cells remains uncertain. Although successful outcomes have been reported in some fields, such as cardiology and haematology, many clinical trials and therapeutic applications have failed due to problems arising in the differentiation processes and the appearance of tumours.

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

CRISPR used in viable human embryos and germline genetic modification. An ethical apprach

From an ethical point of view, the use and destruction of human embryos, members of our species and worthy of full dignity is completely unacceptable and, it should be noted,  these experiments involve genetic modification of the germline, the safety of which is still far from being guaranteed

On 9th March this year, New Scientist reported the first results obtained by a team of scientists in China who had applied the CRISPR gene editing technique in normal human embryos.

This technique has already been applied in China on two occasions in non-viable human embryos, which have a limited capacity for development and so would be unable to result in the birth of a child, even if implanted in a woman. The efficacy of the technique was very low in both studies, giving rise to numerous off-target mutations (in parts of the genome where nothing should have happened).

In England, gene editing in embryos has already been approved, which in theory will use embryos left over from in-vitro fertilisation treatments. However, the results of this research have yet to be published.

Details of technique applied

In the aforementioned study published in New Scientist, the technique was applied to six embryos with some mutation in their DNA (they had been created purposely to have these mutations, fertilising eggs with sperm from men who had a hereditary disease). The genome was correctly repaired in only one of these embryos, but in another two, the repair occurred only in some cells. In a fourth embryo, CRISPR introduced an undesired mutation, while in another two, the technique did not work.

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

All we like SHEEFs, Part 2

Carrying on with last week’s musings…

In thinking further, I think my attempt was confused by conflating the moral status of a SHEEF—a synthetic human entity with embryo-like features, something more than a clump of cells of human origin, but less than a human being—with reasons why I might want to hold that nobody should ever make certain sorts of SHEEFs.

Again, SHEEFs are human, not non-human.  But they may not command a “right to life” in every instance.

I would return to a statement I made last week, that any totipotent human entity, that is, any human entity capable of developing into a full human being under the right circumstances, should be accorded a full human right to life from the moment he or she comes into existence.  We other humans ought to give him or her a chance to live, care for him or her as one of us, grant him or her any research protections extended to human research subjects in general, and so on.  So-called human “embryos in a dish” would be in this group.

The same cannot be said for individual human cells, including human gametes formed from cells like induced pluripotent stem cells.  There may be arguments why those ought not to be produced, but that is for another time.

I would not say that a laboratory-created or sustained human heart, for example, ought to be protected from instrumental uses, including destruction for the research enterprise.  I think I would want to argue that we humans ought not make such a thing as part of a human-non-human animal hybrid, but again, that’s a different argument.   Such a hybrid would not make human moral claims on us to be preserved and cared for as humans.

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: Biological Bubble Machine

Credit: Chi Zhao, David Busch, Connor Vershel, Jeanne Stachowiak, University of Texas at Austin

As kids, most of us got a bang out of blowing soap bubbles and watching them float around. Biologists have learned that some of our cells do that too. On the right, you can see two cells (greenish yellow) in the process of forming bubbles, or plasma membrane vesicles (PMVs). During this blebbing process, a cell’s membrane temporarily disassociates from its underlying cytoskeleton, forming a tiny pouch that, over the course of about 30 minutes, is “inflated” with a mix of proteins and lipids from inside the cell. After the PMVs are fully filled, these bubble-like structures are pinched off and released, like those that you see in the background. Certain cells constantly release PMVs, along with other types of vesicles, and may use those to communicate with other cells throughout the body.

This particular image, an entrant in the Biophysical Society’s 2017 Art of Science Image Contest, was produced by researchers working in the NIH-supported lab of Jeanne Stachowiak at the University of Texas at Austin. Stachowiak’s group is among the first to explore the potential of PMVs as specialized drug-delivery systems to target cancer and other disorders [1].

Until recently, most efforts to exploit vesicles for therapeutic uses have employed synthetic versions of a different type of vesicle, called an exosome. But Stachowiak and others have realized that PMVs come with certain built-in advantages. A major one is that a patient’s own cells could in theory serve as the production facility.

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

Engineered Bone Marrow Could Make Transplants Safer

“We’ve made an accessory bone that can separately accommodate donor cells. This way, we can keep the host cells and bypass irradiation,” Varghese said.

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

Muscle Enzyme Explains Weight Gain in Middle Age

Thinkstock/tetmc

The struggle to maintain a healthy weight is a lifelong challenge for many of us. In fact, the average American packs on an extra 30 pounds from early adulthood to age 50. What’s responsible for this tendency toward middle-age spread? For most of us, too many calories and too little exercise definitely play a role. But now comes word that another reason may lie in a strong—and previously unknown—biochemical mechanism related to the normal aging process.

An NIH-led team recently discovered that the normal process of aging causes levels of an enzyme called DNA-PK to rise in animals as they approach middle age. While the enzyme is known for its role in DNA repair, their studies show it also slows down metabolism, making it more difficult to burn fat. To see if reducing DNA-PK levels might rev up the metabolism, the researchers turned to middle-aged mice. They found that a drug-like compound that blocked DNA-PK activity cut weight gain in the mice by a whopping 40 percent!

Jay H. Chung, an intramural researcher with NIH’s National Heart, Lung, and Blood Institute, had always wondered why many middle-aged people and animals gain weight even when they eat less. To explain this paradox, his team looked to biochemical changes in the skeletal muscles of middle-aged mice and rhesus macaques, whose stage in life would be roughly equivalent to a 45-year-old person.

Their studies, published recently in Cell Metabolism, uncovered evidence in both species that DNA-PK increases in skeletal muscle with age [1]. The discovery proved intriguing because the enzyme’s role in aging was completely unknown.

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 IVF Keepsake?

As a father of two teenagers (and one who will join that esteemed company in a month), I am fluent in “sarcasm,” the native tongue of this group. Mine only use English sparingly, to do business. So, I often read headlines of stories in newspapers (remember those?) and online as sarcastic, and the articles they lead as spoofs. This one, in the “Parenting” section of an Australian web journal called “Kidspot,” immediately led me there. It speaks of a company that will take embryos from in vitro fertilization (IVF) that have not been implanted, and for which the biological parents have no plans of implanting, and turn them into keepsake jewelry. But this is no spoof.

The couple interviewed in the piece, having completed a 6-year journey through infertility and IVF, has a 4-year old son and twin toddlers. With seven remaining embryos, they had a decision to make. For them, “Donation wasn’t an option, the annual storage fee was an added financial strain, and disposing of them unimaginable.” Enter a company called “Baby Bee Hummingbirds,” who placed the embryos in a heart-shaped pendant.

My first impulse, not without some merit, was to find this all a rather ghastly business. Each of these embryos is a unique genetic human created in the image of God. I find myself critical of parents who don’t seem to have fully thought out the ramifications of fertilizing ten or more eggs. If these are genuinely human beings, then the creation (if that’s the right word) of “leftovers” is itself deeply problematic.

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.