Regeneration & Enhancement

Current estimates put the number of cells in an average human body at 37.2 trillion. A cell has three parts: membrane, cytoplasm and nucleus. The nucleus is the control centre and contains the DNA, which stores genetic instructions to create an organism. The nucleus also holds RNA and proteins. RNA influences how genes are read, which determines individual characteristics. The nucleus also contains 23 pairs of chromosomes, which consist of a strand of DNA with hundreds or thousands of genes. A gene is a segment of DNA with information on heredity. The 20,000 or so genes in the genome also encode information for making proteins, which are the building blocks for making all body structures (skin, tissue, organs etc).

Gene therapy began in the 1990s, when researchers discovered how to correct or influence how genes function. This knowledge was used in new treatments for blood disorders and degenerative muscle diseases. Gene therapy delivered a functional copy of a damaged or missing gene into affected cells, using a virus as courier. As technology has progressed, some newer approaches have moved away from the delivery of healthy genes and instead directly target an affected gene within the cell. In particular, the CRISPR method employs molecular tools that can modify or remove the affected gene. This method of gene editing was initially used in trials focused on specific conditions, such as sickle cell disease. Scientists are now investigating a range of treatments for cancers, neurological diseases and autoimmune disorders.

While the idea of regeneration has long been central to the understanding of health and illness, the development of specialised medicine and the ability to drill down to the molecular level have given it great potency in the search for preventative treatments and cures for modern intractable diseases. Research into the behaviour and unique qualities of stem cells now plays a vital role in regenerative medicine, which involves replacing or renewing damaged or diseased cells, tissue or organs to restore their normal function. These are the shapeshifting cells that enable us to develop from a single cell into an adult human being, to make new tissue, heal broken bones and replace injured skin.

We have to make cells constantly to keep our bodies functioning and we rely on stem cells to replace specialised cells that are impaired or used up. Stem cells are defined by two key characteristics: the ability to continuously divide and produce exact copies; and the ability to change into a specialised type of cell. Stem cell therapies are currently used in certain surgical operations, such as bone marrow transplants and skin grafts. Promising advances include initial success in the use of stem cells to reverse type 1 diabetes and gene-editing of bone marrow stem cells to treat a specific blood disorder. People who may eventually benefit from stem cell treatment include those with spinal cord injury, heart disease, Parkinson’s disease, stroke and osteoarthritis.

The next generation of gene and stem cell therapies raise many ethical issues, not least that they will be hugely expensive and many people will be unable to afford them. Scientists will also need to stay aware of the known and emerging risks, such as the finding that a proportion of lab-grown stem cells may develop cancer-causing mutations. Future gene editing in human embryos will create a whole new set of issues, such as the potential to maximise desired attributes in the newborn baby by altering its genetic make-up, while it is easy to imagine how treatments for specific conditions may morph into selective body or brain enhancement. For desperate patients and their families, there is another risk – the spread of unauthorised stem cell clinics that take advantage of regulatory loopholes and experiment with unproven treatments and supposed cures.

Stem cells are used in the lab to grow organoids – tiny tissue cultures that can replicate much of the complexity of an organ, or convey aspects of it. Study of organoids can provide insights on human development and disease, as well as allowing scientists test new drugs. Novel technologies include: implanted 3D-printed scaffolds for bone and tissue regeneration; and retinal organoids grown from skin stem cells. Researchers have also succeeded in created mini-hearts and mini-brains, which are starting to act like developing human hearts and brains. This could possibly lead to a form of consciousness, where lab-grown brain organoids become capable of thought and human-like emotions, as their size and lifespan increase. They have already reached a point where scientists think they show signs of intelligence, and experts are wondering if and when they should be accorded legal status, such as the right not to be treated badly.

The first successful human organ transplant was performed in 1954, when a kidney was donated between identical twins. Use of drugs to combat rejection has allowed some types of transplant operations to become routinely effective, with successful womb transplants from living donors being a recent advance.  The world shortage of available human organs means that xenotransplantation (animal to human) also continues to develop, with current lab trials including the use of hearts and kidneys from genetically modified pigs. The goal of using a patient’s own cells to grow stem cell-based internal organs for transplantation back into their body has not yet become reality.

The development of neural implants to assist people with various conditions is progressing rapidly and producing some remarkable results. These implanted devices work by communicating electrical signals to and from the brain and between the brain and body, so that (for example) someone paralysed from the neck down is able to carry out a physical action, someone who has had a severe stroke can recover a form of speech, or someone who has epilepsy is protected from the brain impulses that trigger seizures. The technology of brain-machine interfaces, which now encompasses deep brain stimulation and the use of AI, is targeting a broad range of health problems and illnesses, including chronic pain, tinnitus, brain cancer, mental disorders and Parkinson’s disease.

In the Lifespinners world of 2048, regenerative medicine has made enormous strides, our modern life-threatening diseases no longer trouble its privileged older residents and the focus is turning to experimental methods of brain and mind enhancement. The issues this raises are highlighted by 80-year-old Isabel, who declares: ‘I don’t want to get into mind … control, exposing our most intimate thoughts and treating our inner space like it’s outer space, a frontier of discovery and something to battle over, mine for resources and colonise for human expansion.’ Despite these objections, she signs up for the lab trial aimed at enhancing social intelligence and empathy, while Trish, her close friend and rival, chooses to join a trial concerned with the curation of personal memories.

Returning to the present day, there is a rapidly growing industry focused on the production and marketing of cognitive-enhancing substances (nootropics) in the form of non-prescription supplements, drinks and various foods. Some of these are based on well known traditional medicines and natural substances, while others are synthetic chemical compounds. Their effects on the brain can include increased blood circulation and oxygen flow, with additional nutrients generating more energy, but these effects may be small in terms of their power to boost specific aspects of cognitive performance in a healthy brain, such as improved memory or increased creativity.

In the field of healthcare, AI is regarded as an invaluable aid in tasks such as assessing cancers, recognising anomalies on imaging tests and predicting level of risk in childbirth. It can also help in the design of drugs and the search for clues in curing serious diseases. In addition, it can collect an unprecedented amount of comprehensive and holistic data on a person’s state of health and medical history and has the power to combine these disparate data to inform accurate diagnosis and the best treatment options.

Like other specialities, mental health is a developing field for AI, with some experts envisaging digitally-driven personalised care that offers ready tools to manage challenging situations. Therapy chatbots are becoming more common in treatment and some draw on well-recognised methods such as Cognitive Behaviour Therapy, which has a specific structure and set exercises. This can reduce the risk that the chatbot acts unpredictably, although research is still needed on ways to ensure that they are reliable and don’t cause harm. There is also concern that characterisations of chatbots as following a therapeutic path, or indeed being therapists at all, can mislead vulnerable patients and give them unrealistic expectations. On the positive side, some patients may find that they relate more easily with a bot than with humans and this might boost wellbeing.

Beyond healthcare, present-day robots come in a bewildering variety of shapes and sizes, ranging from the tiniest nanobot to giant industrial machines. While many traditional robots have rigid structures, soft robotics has brought in novel materials and features that can include sensory skins and fabricated muscles. This has led to flexible devices that give the robot a sense of touch and an awareness of the surrounding environment. The technology is expected to have multiple future applications in areas such as the design of surgical tools and prosthetics. Bionic limbs have moving parts that are electronically controlled and allow for precise control and flexibility, making them potentially attractive to people who are seeking bodily enhancement or augmentation, rather than a vital replacement part.

Despite the considerable hype and great expectations, an autonomous, multi-functioning robot that can carry out all the household tasks while we relax and socialise is still quite far from becoming a reality. Advances are being made in the operation of robots operating semi-autonomously with human control, but the complexities and unexpected occurrences of the real world still present big challenges to machine intelligence working alone in many environments.

Turning to advances on the near horizon, mini magnetic robots and computer-designed organisms (xenobots) made from animal stem cells may have many important practical uses, such as transporting medicines within the body or extracting foreign objects. The current generation of robots have expanded out from manufacturing and computer gaming environments into more personal social contexts, such as residential care homes and schools. In these settings, they need to be relatable and trustworthy. Studies have explored the peculiar Uncanny Valley theory, which suggests that humans get more uncomfortable as robots become more human-like. While there are cognitive and evolutionary explanations for this response, it might steadily reduce with greater familiarity, along with confidence (hopefully) that we humans remain in ultimate control.

Virtual reality (VR) is rapidly expanding in healthcare, where it has proved to be an effective pain relief tool. Being immersed in a calming virtual landscape can reduce pain during unpleasant medical procedures. Digital avatars have also been used to represent the voices heard by people with psychosis, while surgeons in different geographical locations have performed surgery together and VR therapy is employed to support people with conditions ranging from autism to visual impairment, cancer and mental ill-health. Patients are given tasks to carry out in virtual environments, facilitating a holistic approach that extends to individual lifestyle and other factors relevant to their condition. In another emerging therapy, VR is being used to help people overcome cocaine addiction through ‘cue exposure’ to realistic situations that trigger the urge to take the drug. Some psychologists are also now using a combination of virtual reality and a psychedelic substance such as psilocybin, which shows promise in making the brain more flexible through new neural connections and helping the patient to tackle deeply ingrained and unhelpful thought patterns.

Virtual representations of the real world – known as digital twins – are already common in industry. As examples, there are digital doubles of cities, ports and power stations. The idea has moved into biology, with predictions that humans may soon have a digital twin created at birth. In personalised medicine, the twin could be used to inform medical decisions on treatments and predictions of how a particular disease might develop. Many projects are at an early stage but they include research aimed at twinning or emulating the brain. As with growing brain organoids, digital brain twinning poses stark ethical questions: Who owns the twin? Does the twin have rights? Where does its data go after the person dies? And perhaps most intriguingly, what happens if someone wants to choose their super-fast digital brain in preference to their natural one?

Edited October 2024