The University of Southampton

Engineering Replacement body parts 2024-2025

An interdisciplinary module

The Amazing Spider Goat

Several years ago, in my GCSE biology class, I first encountered the concept of gene editing and transgenic animals. Since then, I have become very interested in medical devices and biomaterials. Spider goats perfectly combine these topics and pave the way for potentially revolutionary advances in medicine and healthcare.

Spider goats appear to be completely regular goats at first glance. However, they have a secret superpower: the ability to produce the spider silk protein in their milk!

There are various ways to produce transgenic animals. The way it was originally achieved in spider goats was by taking some skin cells from the goat and inserting the gene from the spider that creates the silk protein into the nucleus. The nucleus could then be removed from the skin cell and put into an egg cell, which was then implanted into a goat. The result is a goat that can produce the protein for spider silk in its milk. [1]

In an article written by T. Miller [1], she interviews Justin A., who helped create the original herd of these spider goats, and he explains how the silk is extracted from the goat’s milk.

Firstly, the goat’s milk is collected and frozen. Once the milk has thawed, it can be purified. The first step is to remove any fats and then filter out the smaller proteins. The spider silk protein is separated by selective precipitation (separating a solid from a solution [2]) and washed. Once a purified form of the spider silk protein is obtained, it is suspended in water and placed in a microwave. The purified liquid silk protein can be easily manipulated into its desired form.

THE AMAZING SPIDER GOAT (a short comic)

The type of spider silk focused on by most studies is dragline silk. It has some interesting properties, such as having a good balance between strength and elasticity to enable the spider to catch flying prey. These unique properties means that it surpasses the majority of all natural and man-made materials [3].

Some of its most beneficial properties [3]:

  • Strong
  • Tough
  • Biocompatible (compatible with living tissue [4])
  • Minimally immunogenic (produces an initial immune response, but there are no long term effects)
  • Exceptional cytocompatibility (has very little effect on the structure and function of tissues it comes into contact with [5])
  • Slow degradation rate

These properties are a result of mainly two spidroins (proteins) that comprise the silk: MaSp1 and MaSp2. These proteins have very repetitive amino acid sequences that lead to the formation of specific final structures that give the silk its unique physical properties.[3]

The use of spider silk in medicine is certainly not a new idea. In fact, it was even used by the ancient Greeks and Romans to promote wound healing [3]!

The possibilities for the biomedical applications of spider silk is what particularly interests me about this topic, since it relates to the majority of the modules I am currently studying. For example, both this module and the Orthopaedic Biomechanics module have covered tissue engineering and spider silk has shown great promise to enhance current solutions in this area [7]:

  • Skin regeneration and wound dressing
    • It has been shown to promote the healing of burns
  • Cartilage and tendon tissue engineering
    • Acts as a good scaffold because it degrades relatively slowly and scaffold shouldn’t degrade faster than the rate of new tissue formation [3]. It is also very biocompatible.
  • Neural tissue engineering
    • Has been proven to aid in nerve regeneration

Spider silk also has desirable properties for use in drug delivery and its high tensile strength and excellent biocompatibility make it a good choice for a suture [7].

  • The spiders are very territorial, so are difficult to keep [3]
  • The silk needs to be made in large quantities to be useful

As much as I see a great potential in the use of spider silk to improve healthcare, I understand that there are ethical concerns surrounding the use of transgenic animals. The procedures the animals go through are invasive (e.g. superovulation and taking tissue samples). It is also felt by some people that altering animals in this way is disrupting the natural order of the universe. Ultimately, it is important we take into account the welfare of animals when doing this type of research.

[1] T. Miller, “The Spectacular Spider Goat – Goat Journal,” Goat Journal, Aug. 12, 2021. https://goatjournal.iamcountryside.com/kids-corner/the-spectacular-spider-goats/ (accessed Mar. 23, 2025).

[2] “Selective Precipitation — Overview & Examples,” expii. https://www.expii.com/t/selective-precipitation-overview-examples-8536 (accessed Mar. 24, 2025).

[3] F. Bergmann, S. Stadlmayr, F. Millesi, M. Zeitlinger, A. Naghilou, and C. Radtke, “The properties of native Trichonephila dragline silk and its biomedical applications,” Biomaterials Advances, vol. 140, p. 213089, Sep. 2022, doi: https://doi.org/10.1016/j.bioadv.2022.213089.

[4] Merriam-Webster, “Definition of BIOCOMPATIBILITY,” Merriam-webster.com, 2017. https://www.merriam-webster.com/dictionary/biocompatibility (accessed Mar. 23, 2025).

[5] M. F. Sigot-Luizard and R. Warocquier-Clerout, “In Vitro Cytocompatibility Tests,” Test Procedures for the Blood Compatibility of Biomaterials, pp. 569–594, 1993, doi: https://doi.org/10.1007/978-94-011-1640-4_48.

[6] Bronwyn Thompson, “Bionic silkworms with spider genes spin fibers 6x tougher than Kevlar,” New Atlas, Sep. 21, 2023. https://newatlas.com/materials/silkworms-spider-genes-spin-fibers/ (accessed Mar. 23, 2025).

[7] B. Bakhshandeh, S. S. Nateghi, M. M. Gazani, Z. Dehghani, and F. Mohammadzadeh, “A review on advances in the applications of spider silk in biomedical issues,” International Journal of Biological Macromolecules, vol. 192, pp. 258–271, Dec. 2021, doi: https://doi.org/10.1016/j.ijbiomac.2021.09.201.

The Controversial Future of Inter-Species Chimeras

Before the stem cells lecture, I was not aware of inter-species chimeras. During the lecture it was proposed that they could be the solution to organ shortages. I found this an interesting proposition, and imagined a world where no one dies waiting for an organ. However, the thought growing of organs in another animal made me uneasy, and since learning about it, I’ve been wondering whether I would accept one if I needed it.

So what are they?

An inter-species chimera is an organism containing cells from two or more genetically distinct species. After further research I found that pigs are the most promising candidates for this research due to similarities in organ size.

Process of their creation for organ transplantation:

Video: me

As I learned more, I gained an appreciation for the innovation of genetic engineering. In theory, inter-species chimeras could be used to provide unlimited transplantable organs, but at what cost?

Image: mouse-human chimeric embryo with human cells labelled with green fluorescent protein by Jian Feng [1]

How far can we really go?

Despite promise with recent experiments forming tissues, inter-species chimeras face massive challenges. The high risk of organ rejection reminded me how fragile biology is and how even innovations struggle to overcome nature.

There are also numerous ethical concerns. How does this technology challenge our perspectives on humanity and morality? I thought about how others would react to the process of their creation. Recognising the controversy of this topic, I surveyed the public to gauge their opinions.

“The most egregious abuses of medical research” – George W. Bush describing human–animal chimeras [2]

The results were evenly split, reflecting the diverse range of beliefs that should be considered.

Reasons ranged from fear of the unknown to ethical concerns. Many of those in favour argued saving lives justifies their use. Chimera creation involves genetic modification and experiments that could cause pain or distress to animals. Unlike human, animals cannot give consent. Is it ethical to use them for experiments solely for human benefit? Before their use, key concerns must be addressed first.

“The more you can show that it stands to produce something that will actually save lives … it shifts the scale of risk-benefit assessment in favour of pursuing research and away from those concerns that are more philosophical” – Vardit Ravitsky, a bioethicist [3]

To alleviate concerns, regulatory measures could be enhanced, implementing welfare assessments. Involving the public in decision-making would also help align advancements with societal values. However, even different countries have different opinions, and religious and cultural perspectives are also highly diverse.

It is clear that this topic needs to be approached sensitively, considering both individual beliefs and societal values.

What other choice do we have?

The demand for organ transplants is not decreasing. So, what are our other options? One possible solution is in-vitro stem cells allowing for patient-specific organs. Integrating techniques such as 3D bio-printing could also help us move towards a brighter future. [4]

Image: 3D bio-printing used to synthesise tissues [5]

My final thoughts

I’m torn between saving lives and animal welfare. After more research, the complexity of the issues is only more apparent. The number of articles expressing concerns has greatly impacted my perspective, highlighting the key considerations needed before implementation.

I believe we should innovate, but within boundaries. Should we set clear limits on inter-species organ growth, and if so, what should those be? Whilst some have argued the potential to save lives outweighs concerns, I don’t think it is that clear cut. The question isn’t just whether we can create inter-species chimeras, but whether we should.

References:
[1] https://www.the-scientist.com/chimera-research-opens-new-doors-to-understanding-and-treating-disease-71254
[2] https://www.pnas.org/doi/10.1073/pnas.1615787113
[3] https://www.washingtonpost.com/news/speaking-of-science/wp/2017/01/26/scientists-create-a-part-human-part-pig-embryo-raising-the-possibility-of-interspecies-organ-transplants/
[4] https://www.sir.advancedleadership.harvard.edu/articles/engineering-high-tech-solutions-organ-shortage#:~:text=Joseph%20Vacanti%2C%20Professor%20of%20Surgery,an%20interdisciplinary%20field%20that%20applies
[5]https://blogs.manchester.ac.uk/mioir/2023/06/09/can-3d-bioprinting-cure-organ-trafficking/

Can we sell medical waste?

Immortal cells

I recently read The Immortal Life of Henrietta Lacks by Rebecca Skloot1; the remarkable story of an American woman whose cervical cancer was used to make the first immortal cell line, HeLa. In vitro cell research is normally constrained by the Hayflick limit2; cell lines die out after a few days. Lacks’ cancer was so aggressive that its cells could divide indefinitely, providing an invaluable biological material still used today. Incredibly, few know her name. The cells were used without her knowledge or consent, and her family knew nothing for twenty years.

This story raises important questions about human tissue ownership, notably: who owns medical waste, and can it be sold? Skloot heavily implies that the Lacks family should be compensated for Henrietta’s cells, but I’m not sure it’s so simple.

A video by Hank Green on SciShow, with further information about immortal cell lines and HeLa cells.3

Tissue ownership in the UK

My friend works for the Southampton Imaging4 group and routinely uses femoral heads, leftover from hip replacement surgery, in his research. Recently introduced to tissue ethics, I had several questions for him. My Gran had a hip replacement – are scientists experimenting on her bone? Could they extract stem cells from the marrow and make a cell line like HeLa?

Thankfully, the Human Tissue Act 20045 (HTA) restricts research on tissue to licensed labs and requires informed consent from all donors. My friend assures me that strict protocols are followed, from surgery to the lab to disposal, and that his lab must comply with the Declaration of Helsinki6.

What does this mean for Lacks’ family?

Henrietta Lacks was treated unethically. Her cells should not have been used without her consent, violating her dignity when she was extremely vulnerable. Furthermore, it’s now possible to sequence HeLa’s genome, raising concerns about Lacks’ and (her family’s) privacy. Unfortunately she died in 1951, before widespread adoption of informed consent as best practice.

Henrietta Lacks. Photo from the National Geographic7

In her book, Skloot implies that Lacks’ family should be paid for the cells. It’s important to note that HeLa cells are not full organs, nor were they healthy – if not for their scientific usefulness they would have been deemed medical waste. In the US it is illegal8 to sell one’s organs, but consent and payment law for other tissue is more permissive than in the UK, where selling human tissue is banned.

I strongly support the UK position that selling human tissue for money, regardless of purpose or usefulness, is unacceptable. Tissue derived from a person’s body deserves to be treated with more dignity than a mere commodity.

Even if the act of selling one’s own tissue were ethical, a culture that allows it is not. It would encourage objectification of the human body and provide incentive for organ theft. Nobody should have to resort to selling their tissue. Meixuan Li’ 9 wrote a post exploring this concept taken to a dystopian extreme; prisoners exchanging their organs for reduced sentences. The very idea is abhorrent.

This is why, while Henrietta Lacks was wronged, her family should not be financially compensated. Payment for human tissue, even retrospectively, is morally unacceptable.

Sources

  1. Skloot R. The Immortal Life of Henrietta Lacks. Crown Publishing Group (2010) ↩︎
  2. Hayflick’s handy guide to immortality and cell senescence. The Genetics of Basic Things and Stuff. 30th November 2022 (cited 24th March 2025). Video: 5:13 min. Available from: https://www.youtube.com/watch?v=w5SBZOa_qAg ↩︎
  3. Immortal Cells Turn 96. SciShow. 1st August 2016 (cited 20th March 2025). Video: 4:41 min. Available from: https://www.youtube.com/watch?v=sXY6-wLesYY ↩︎
  4. Southampton Imaging. University of Southampton (cited 21st March 2025). Available from: https://www.southampton.ac.uk/research/institutes-centres/southampton-imaging ↩︎
  5. Legislation. Human Tissue Authority (cited 21st March 2025). Available from: https://www.hta.gov.uk/guidance-professionals/codes-practice-standards-and-legislation/legislation ↩︎
  6. WMA Declaration of Helsinki – Ethical Principles for Medical Research involving Human Participants. World Medical Association. 2024. (cited 21st March 2025). Available from: https://www.wma.net/policies-post/wma-declaration-of-helsinki/ ↩︎
  7. Marc Silver. A New Chapter in the Immortal Life of Henrietta Lacks. National Geographic. 2013 (cited 21st March 2025). Available from: https://www.nationalgeographic.com/science/article/130816-henrietta-lacks-immortal-life-hela-cells-genome-rebecca-skloot-nih ↩︎
  8. Can you sell organs in the United States? Donor Alliance; Tissue and Organ Donation. 2025. (cited 21st March 2025). Available from: https://www.donoralliance.org/newsroom/donation-essentials/can-you-sell-organs/ ↩︎
  9. Li M. Prisoners ‘Donating’ Organs for Sentence Reduction: Should the Punishment Fit the Crime? 12th March 2025 (cited 21st March 2025). In: Engineering Replacement Body Parts 2024-2025. Available from: https://generic.wordpress.soton.ac.uk/uosm2031-2025/2025/03/12/prisoners-donating-organs-for-sentence-reduction-should-the-punishment-fit-the-crime-2/ ↩︎

A Joint Effort: NHS or Private – What’s the Right Option?

Audio transcript:

The lecture series by Prof Dickinson on prosthetic joints prompted my thoughts on this topic with my tennis interest in Andy Murray and how it has affected close family friends.

The comeback of Murray following his hip resurfacing was astounding. Watching him win the European Open tournament in Belgium post-surgery demonstrated his determination and ability to compete at the highest level.

Andy Murray
An image of Andy Murray playing at the 2012 US Open. Available at https://commons.wikimedia.org/wiki/File:Andy_Murray_(US_Open_2012).jpeg (Accessed: 14/03/2025). By Francisco Diez, licensed under the Creative Commons Attribution 2.0 Generic license from Wikimedia Commons.

Murray’s hip resurfacing was done privately and quickly. I will share two stories from close family friends who have had very different experiences on knee replacements.

What is a knee replacement?

This topic is explained here. The summary is that knee replacements are used to treat pain and stiffness in the joint, usually caused by osteoarthritis. The process involves making an incision in the knee with metal and plastic replacement parts fitted as seen in the image below.

Total knee replacement image
An image of the components for a total knee replacement. Available at https://commons.wikimedia.org/wiki/File:Knee_Replacement.png (Accessed: 14/02/2025). By BruceBlaus, licensed under the Creative Commons Attribution-Share Alike 4.0 International license from Wikimedia Commons.

How successful are knee replacements?

A 2020 NHS report found that from over 80,000 patients, 75% responded that they felt much better following the operation with 64% being very satisfied with the results. The success of this treatment is why I feel access to them is so important, but the question of how to make it fair is challenging.

Wait times

The NHS has a very open website called My Planned Care. Taking the University Hospital Southampton statistics accessed on 21/03/2025, in the orthopaedic department the average wait time for treatment was 21 weeks. This led me to read a journal article “Who should have priority for a knee joint replacement?”. The degree of suffering, payment of National Insurance and caring for dependants are reported as the most important factors.

My friends

Ms D went down the private route for her knee replacement and had the operation within three weeks. Before this time, she had put on weight and was withdrawn socially. After the operation, Ms D’s mobility improved, and she resumed frequent international travels.

Ms C suffers from severe knee pain such that she rarely travels far on foot, something that has dampened her usually bubbly spirits. Ms C is opposed to private treatment. She also has a close friend who had a private knee replacement that was infected. Ms C is on an NHS waiting list for knee replacements and is hoping to have the operation in the next few months.

My dilemma

Both people have very different outlooks. My main concern is regarding quality of life. Ms D has now sadly passed away, but she lived ten years with her knee replacement. Ms C is in her late seventies and suffers. I tried to put it to Ms C’s husband in a recent phone call about “Why don’t you consider the private option?”, but it was quickly shot down. If it could be afforded, then the quality of life improvement would be massive, surely it would be worth the money?

Concluding thoughts

Having been a medical student for a couple of years before switching university courses, I have seen first-hand how the NHS system is struggling. I often have a pessimistic view on its survivability in its current form and I see private healthcare as a necessary evil.

Knowing that both suffered greatly, with Ms D having a huge quality of life improvement, makes me uncomfortable with the fact that this could’ve been avoided in Ms C’s case. I find myself feeling regret that Ms C hasn’t put her morals aside for the benefit of her physical and mental wellbeing.

The video below summarises my debate

Unwilling Immortality: The Stolen Cells of Henrietta Lacks


Previous to our lectures on bioethics, I believed that I had a very uncompromising way of assessing scientific ethical concerns: with some exceptions, the advancement of science was worth the cost of a few. From someone who grew up surrounded by scientific minds, this utilitarianism made sense. Why shouldn’t we strive for “the greatest happiness of the greatest number” as stated by Jeremy Bentham? However, since learning about watershed moments in history like the Nuremberg trials, I have learnt that not everything can be so easily segregated into right and wrong. This lead me to reflect on a scientific controversy that I had learned of in my previous year of study: HeLa cells.


What are HeLa cells?

HeLa cells were the first immortal human cell line to be created. Derived from cervical cancer cells, they were cloned in 1953 and freely given to researchers for use in labs. Since then, they have been at the forefront of many medical breakthroughs: from gene mapping to cancer research. Arguably, their most notable use was in the development of the Polio vaccine in 1952.


The Woman Behind The Cells

Henrietta Lacks was an African-American woman born in August 1920. She died of an aggressive cervical cancer at the John Hopkins hospital at the age of 31. Unbeknownst to her, one of the gynaecologist who performed her biopsies, Dr Grey, had removed a sample of the tumour for research purposes. He was able to isolate the cancer cells and thus create the first immortal human cell line: HeLa. Knowledge about the use of her cells was not revealed to the family until an article published in Rolling Stone until 1976. Since then, there has been much conversation about the unethical obtainment and distribution of Henrietta’s cells.

Henrietta Lacks

Learning from the Past

The main issue regarding HeLa cells was lack of consent. Although this was acceptable at the time, since then, Henrietta’s name has been shared alongside her medical record and even her cell’s genome. Following this, the Henrietta Lacks Foundation, established in 2010, provides grants to descendants, and families whose bodies have been used for research without consent. Henrietta’s descendants have worked tirelessly to create rules over the use of HeLa cells but there is still work to be done. Suggestions of revisions to the NIH Common Rule to protect human participants in US government funded research regarding consent have been put forward. In addition, there is a general consensus that institutions that have used HeLa cells must examine how they will right histories previous wrongs.


What are my Thoughts?

From a scientist’s perspective, the actions of Dr Grey seem understandable. To some, even justifiable. To me however, it is a clear example of where our thirst for knowledge clouds our judgment on what is morally right. Informed consent is a relatively easy standard to meet when obtaining samples for research, especially in cases such as these where the patient is of sound mind. I do not condone the actions of Dr Grey. Despite this, the argument could be made that to remove or limit both past and future contributions of the HeLa cells to modern medicine would be both a disservice to Henrietta. Without her, many scientific advancements would not have been possible. Instead, I think it possible to find a middle ground. One which allows the continued use of the HeLa cells in research whilst also acknowledging their origins.

So reader, over to you. What are your thoughts on the continued use of these cells?


Learn More

If you’re interested in Henrietta Lack’s story, you can find out more with these links below:

The Future and Ethics of Stem Cell Research

It is clear that the future of medicine lies in stem cell research, offering treatment possibilities to an enormously wide range of diseases using the body’s own healing mechanisms. Despite this, stem cell research faces many ethical implications (particularly embryonic stem cells), posing a dilemma between morality and furthering scientific innovation.

What are Stem Cells

Stem cells are undifferentiated cells that have the potential to become many types of specialised cells. The ethical problems lie in collecting the stem cells a there are two separate types: adult (somatic) and embryonic. Adult stem cells are multipotent, meaning they can differentiate into a wide range of specialised cells, but they are limited and they eventually sensece. In comparison, embryonic stem cells are pluripotent, meaning they can divide into any cell type.

Why are Stem Cells Useful?

The potential of stem cells is massive, it is believed that they could be involved in the cure for Parkinsons’s, Alzheimer’s and type 1 diabetes. Conditions relating to tissue damage could become things of the past as scarred tissue from liver cirrhosis or scarred heart tissue from heart disease can be replaced without the need for an organ transplant. They are also useful in laboratory purposes as they are useful in making ‘knockout mice’. Knockout mice are made from mating two chimeric mice in which you can remove certain genes, giving a great insight into what each gene does.

Ethical Concerns

Adult stem cells pose little ethical dilemma as all the methods used to extract them pose very little risk, the most common being a bone marrow extraction under local anaesthetic. Ethical dilemmas are raised when embryonic stem cells are used because it can be seen as destroying an early human life, raising the ethical question: when does a human life start?

While those who argue against the use of embryonic stem cells argue that the embryo has a potential for life and therefore the elimination of it is equivalent to the taking of a human life. The argument against this is that there are countless spare embryos after fertilisation procedures that would be discarded anyway, so scientific testing that could save and improve lives is not just permitted, but the right thing to do.

To combat these ethical concerns, a surprising discovery was made that by knocking out 4 genes, adult skin cells could be reverted into pluripotent cells. This helps deal with the ethical dilemma of harvesting the stem cells, but it raises more questions relating to the idea of human enhancement.

Conclusion

This ethical dilemma is a cornerstone moment for human scientific research because it creates a line between morality and scientific research. How far are we willing to go to understand how our body works? Is it okay to cross moral lines against embryos in order to save more lives in the future? At what point do biological enhancements make a person inhuman? The answers to all of these questions will be used as the precedent for the future of medicine.

Should women be paid for egg donation? 

A brief introduction

One topic mentioned in the ethics workshop was egg donation. This is the practice of women donating their eggs either for IVF treatments or for scientific research. There is great variation in the payment of women in different cultures, sparking debate over how donors should be compensated.

How does the process work?

The process of egg collection is lengthy, taking two to three months. Genetic screening is also required before the egg collection occurs which follows a few key steps. 

Firstly, hormone treatment occurs on day two of the cycle. This is done via daily FSH injections to boost the number of follicles formed. Secondly, after a few days of FSH injections antagonist injections occur to supress natural hormone production of the cycle. At this stage blood tests and scans are needed to check for responses to the medication. Further antagonist injections then help the eggs mature. Finally, to collect the eggs from the body pain relief via sedation or general anaesthetic may also be required. The collected eggs are then used fresh or are frozen for later use.

The UK law of egg donation

In the UK it is illegal to profit from this practice however compensation of £985 per cycle (one complete round of treatment) is allowed.  This compensation is strictly processed based, not for actual donation and more can also be claimed to cover fees for expenses such as travel, accommodation and childcare.

Egg donation in the US

In the US the ASRM (American Society for Reproductive Medicine) requirements must be met, and it is possible to donate anonymously which is different to the UK law.

The cost of fresh egg donation ranges from $35, 000 to $50, 000 and is not always limited to processed based compensation, differing to UK law.

Ethical arguments in favour of payment

Egg donation is time consuming due to the duration travel and process. Daily injections also make it extremely inconvenient. There is also a risk to the health of the donor including risks associated with medication such as general anaesthetic and there is potential risk to life due to OHSS and side effects.

Counselling is also legally required, demonstrating the large mental health impact which can be long lasting and not fairly compensated for as mental health affects every aspect of life.

These reasons describe how it could be argued that there is not enough compensation for the risk taken by the donors.

Additionally, the US system assigns great value to the donated eggs which is reflected by the price women are paid for their eggs.

Ethical problems with payment for Egg donation

Major problems associated with paying for egg donation include encouragement to undergo a complicated and painful procedure for those that more urgently need money. A monetary incentive and other potential pressures could also introduce ethical issues about true consent which can be eliminated if the process is voluntary and unpaid.

Overall conclusions

It is a difficult topic with no complete solution. The current UK system allowing some compensation to cover the actual cost of donation feels the most appropriate to me as it offers a middle ground where the women are somewhat looked after but no moral compromises are made. However, a slight increase in the maximum compensation limit could better support the women.

Sources:

  1. Donating your eggs | HFEA
  2. Egg Donor Laws by States – A Comprehensive Guide
  3. Egg donor compensation is to triple under new HFEA guidelines – BBC News
  4. How Much Can You Get Paid for Donating Eggs? – GoodRx

Miniature Miracles: How Organs on Chips Are Revolutionizing Healthcare

Organs you can hold in your hands’ sound like the work of science fiction or the canopic jars of the Egyptian pharaohs. But this is not too far from the present with organs tissue being made on chips (and no, not the salt and vinegar kind). These have been hailed by many as the future of drug development  and an alternative to animal testing. I first heard about organs-on-chips about 5 years ago, they were mentioned as a technology of the future. But while looking into drug research with stem cells I rediscovered these chips and wanted to explore how they are used and what the next 5 years could look like.

What are organs on chips (OoC)?

Simply put they are microchips that are designed to mimic human organs. These contain living cells from different organs like the brain, bones, heart and lungs. They were originally theorised by Michael Shuler who envisioned connecting these to make a whole ‘body on a chip’.

Applications- Drug Development

Currently drug development takes an average of £1.22 billion, 13.5 years and 92% of drugs fail the strict regulations. This staggeringly high failure rate is due to testing on animal (generally mice) before humans. Animal testing unreliably predict if drugs will work due to genetic and immune differences to humans. The current inaccurate, expensive, and lengthy process for drugs development demands a new approach.

OoC’s could Refine testing by Reducing and Replacing the use of animal models. These 3R’s are part of the European Union’s guidelines on ethical animal testing. If regulatory authorities allow the use of OoC’s It would reduce public objections to testing drugs and cosmetics on animals. However, a major drawback of organ-on-a-chip technology is that it only mimics single organs. This means it can’t show how drugs are processed in interacting organs, like the stomach, before reaching their target, which could lead to inaccurate results.

Pros and cons

Pros and Cons of animal testing V OoC’s, the colour indicates the outcome: green= positive, yellow= neutral, red= negative.

The future: Patient-on-a-chip

Researchers are currently striving to develop body-on-chip technology. These would connect existing chips together to form a body circuit, that could mimic a drug’s pathway through the body.

Example of the organs that could be included in the body-on-a-chip. Organ-On-A-Chip Technology: An In-depth Review of Recent Advancements and Future of Whole Body-on-chip | BioChip Journal

I can imagine in the future:

Going to your GP with high blood pressure and they suggest several medications - luckily, they are printing your body chip now- with your stem cells, from your frozen umbilical cord stored when you were born. Now the doctor can test each treatment in your body chip and within a couple of hours your prescription is ready for you. It’s for the drug which will work the best for you with the fewest side effects.

Although this may sound a but far fetched, personalised medicine is a key focus in the NHS's strategy to improve outcomes. These have the potential to save millions of lives, but rely on a cell source. Cells from biopsies are generally uncontentious as there are thorough consent procedures and they involve adult cells. To enable personalised body chips, mesenchymal stem cells would be ideal. However this is accompanied by more legal, religious, and social scrutiny. For drug companies to change their historic means of testing there needs to be a regulatory pathway to integrate OoC’s into the clinical trial stages.

The Woolly Mouse: Gene Editing’s Newest Invention

[1] On 4 March 2025, the de-extinction company Colossal revealed its latest research: the Woolly Mouse. Unlike typical mice which have short, grey hair, this mouse has long, shaggy, tawny-toned hair, mimicking the hair of the Woolly Mammoth. To achieve this, the scientists used many gene-editing techniques to modify up to 7 different genes involved in lipid production, and hair type, both of which differ due to the Woolly Mammoth’s adaptations to surviving in the cold.

[3] Gene editing is the process of modifying DNA via deletion, addition or modification of different genes in different plants, bacteria and animals which can change their physical features like eye colour and disease risk. While the concept and techniques have been developed since the late 1900’s, recent developments of a tool called CRISPR/Cas9 have greatly advanced gene editing.

[2] Gene-editing research often takes place in animals as humans and animals share many genes. Mice are often used as they have a short gestation period of 20 and have well established methods for gene editing protocols, allowing rapid testing compared to other animals. While the findings in mice models are not fully translational to human genes or in this case to Woolly Mammoth genes, they can still be used for research and understanding the effect of different genes and different characteristics.

[3] The de-extinction of the Woolly Mammoth could have great effects on the Artic tundra and convert it back to grasslands seen in the ice age. This could then reduce CO2 released into the atmosphere. Other animals which played unique crucial roles in their habitat, like the passenger pigeon, could also have positive long-lasting effects if they were brought back. While true de-extinction involves different technologies, the use of genetic engineering may be able to create modern replica animals with desirable characteristics which could still bring positive environmental impact.

There are many arguments for not using gene editing for de-extinction. If we use small creatures like rats, then it is possible to lose track of them and they could infiltrate other ecosystems. It also raises ethical issues as even if we could bring back these species are people and people in power ready for this? There is no guarantee that once people can bring back a Woolly Mammoth that people wouldn’t monopolise the discovery and create zoos filled with de-extinct creatures or bring back other species purely for monetary gains. Therefore, new laws will need to be put in place to regulate the ethical use of gene editing for de-extinction. If this technology develops it could also lead to a wider acceptance of gene editing and the use of gene editing in humans which comes with another set of arguments.

Overall, the arrival of the Woolly Mouse highlights the innovative research continuing to be done in the field of gene editing. While the mouse is adorable, it highlights the potential ethical issues around gene editing and could start discussions around introducing laws to regulate the use of gene editing for de-extinction, to prevent a real-life Jurassic Park situation.

References:

[1] E. Callaway, “Meet the ‘woolly mouse’: why scientists doubt it’s a big step towards recreating mammoths,” Nature.com, Mar. 2025, doi: https://doi.org/10.1038/d41586-025-00684-1.

[2] R. Chen et al., “Multiplex-edited mice recapitulate woolly mammoth hair phenotypes,” bioRxiv (Cold Spring Harbor Laboratory), Mar. 2025, doi: https://doi.org/10.1101/2025.03.03.641227.

[3] D. Shultz, “Should we bring extinct species back from the dead?,” www.science.org, Sep. 26, 2016. https://www.science.org/content/article/should-we-bring-extinct-species-back-dead

Ctrl+P: Bio-printing, how it works and societal concerns.

Donor organ transplants

The human body has a limited capacity to heal or regenerate compromised organs. Currently these are normally replaced via transplant from a compatible donor, but there can be complications with rejection when the immune system recognises the transplanted tissue as foreign and there is the initial issue of having enough donors within society to provide the organs needed for transplants everyday. Those of us in the UK should be especially aware of donor shortages, given we must opt out of the organ donor register per the Organ Donation Bill (2019) as consent for donation is automatically assumed otherwise.

A possible solution

Bio-printing uses common 3D printing techniques to construct organs or other bio-materials from base cells in a ‘bio-ink’. Potentially, those waiting for organs could have one purpose printed or their damaged organ repaired (with successful stem cell use demonstrated for both), cutting the risk of rejection and wait time.

Printers?, Ink?, Like a regular printer? Bio-inks are predominantly blends of alginate-gelatine that contain desired cells. The properties of this material must be specialised for its use and the method of printing involved, optimal cell growth and tissue integrity has to be maintained for the cell payload, print temperature and pressure can kill the cells during delivery if not set correctly. Simultaneously the gelatin must be viscous enough for delivery and yet achieve a balance of flexibility and sturdiness once in place to replicate organs as if grown in situ.

The printers involved vary, but most may be familiar, inkjet printers similar to the one on your desk (and possibly built by the same company e.g. Hewlett-Packard) heat the ink and eject it onto the build plate via an array of nozzles in the printhead. Stereolithography (already used by hobbyists like myself with non-bio photopolymers), targets UV or visible light onto a build plate, upon which the bio-ink undergoes a chain reaction from liquid gelatine to a solid scaffold for growth under light exposure.

Extrusion printers build a structure with supports layer by layer, the material is either pushed out of a syringe in liquid form under pressure via pneumatics, pistons or screws or fed into a controlled heated nozzle (called a hot end), liquified and deposited directly onto the structure, the latter being the same premise as for FDM (Fused Deposition Modelling) printers.

HP Inkjet bio-printer
Visuals for how the processes work.

Bio-printing in fiction and societal views

Those of you who’ve read books such as Kiln People or Queen of Angels or watched Westworld know the concerns that can arise with bio-printing. Body modification, cloning and exploitation of humans made through bio-printing have been explored in our media, so what standards can we hold bio-printing to? I myself own two (non-bio)printers, they’re incredibly easy processes to pick up and find equipment for (there have been open source instructions to build your own bio-printer for under £400 from Carnegie Mellon University since 2018) and yet there is no sui generis regulatory body governing the entire process, only partial coverage for the biological material itself under the HTA for tissues and HFEA for stem cells.

My closing thoughts

The concerns above are significant, and yet it seems to me the industry might be getting ahead of being assessed and regulated. Although we’re nowhere near printing the hosts, if someone can inexpensively decide to make their own bio-printers, why don’t specific regulation bodies exist and how could they monitor such possibilities when the process can feasibly be completed in the comfort of your own home.

Westworld (tv series) opening- the park’s hosts are automatons with organic bodies.

References

Information on opt-in, opt-out system: https://www.organdonation.nhs.uk/helping-you-to-decide/about-organ-donation/faq/what-is-the-opt-out-system

Ong, C. S., Yesantharao, P., Huang, C. Y., Mattson, G., Boktor, J., Fukunishi, T., Zhang, H., & Hibino, N. (2018). 3D bioprinting using stem cells. Pediatric research83(1-2), 223–231. https://doi.org/10.1038/pr.2017.252

Murphy, S., Atala, A. (2014). 3D bioprinting of tissues and organs. Nat Biotechnol 32, 773–785. https://doi.org/10.1038/nbt.2958

Chung J, Kapsa R. (2013) Bio-ink properties and printability for extrusion printing living cells. Biomaterials Science. http://dx.doi.org/10.1039/C3BM00012E

Kirillova A, Bushev S, Abubakirov A, Sukikh G. (2020) Bioethical and Legal Issues in 3D Bioprinting. Int J Bioprint; 6(3):272. doi: 10.18063/ijb.v6i3.272.

S. Vanaei, M.S. Parizi, S. Vanaei, F. Salemizadehparizi, H.R. Vanaei, (2021) An Overview on Materials and Techniques in 3D Bioprinting Toward Biomedical Application, Engineered Regeneration, Volume 2, https://doi.org/10.1016/j.engreg.2020.12.001.

Herzog, Josha & Franke, Lea & Lai, Yingyao & Rossi, Pablo & Sachtleben, Janina & Weuster-Botz, Dirk. (2024). 3D bioprinting of microorganisms: principles and applications. Bioprocess and Biosystems Engineering. 47. 1-19. doi: 10.1007/s00449-023-02965-3.

Open source instructions for a bioprinter from CMU: https://engineering.cmu.edu/news-events/news/2018/03/23-bioprinter-feinberg.html