The BBC and CNN reported in July 2011 the successful implantation of the world’s first lab-grown stem cell windpipe in a human subject. This project features people from various parts of the globe starting with the patient: a 36-year-old geology student from Eritrea who was studying in Finland. In June 2011, he became the world’s first recipient of a synthetic windpipe. His surgeon, Dr. Paolo Macchiarini, was trained in Italy, Alabama, and France, and taught in Germany and Spain before moving to Sweden, where the surgery was performed. The windpipe was constructed in London, with parts supplied by a Massachusetts biotech company.

The international team of scientists and doctors created a replica of the patient’s windpipe using nanotechnology to build a spongy scaffold. Cells from the patient’s bone marrow (stem cells) and nose (providing the pattern for cartilaginous tissue) were placed around the scaffold. This took place inside a bioreactor to encourage growth of all the various types of cells. After just two days of growth, the new organ was ready for transplant. Since the cells were from the patient, they would not pose a risk of rejection.

Shows a synthetic engineered windpipe or trachea

Figure 1. Shows a synthetic engineered windpipe or trachea.

This is an exciting biotechnology breakthrough that combines innovations in stem cell research and the emerging field of regenerative medicine.

As scientists learn more about stem cells and how to engineer them in the lab, these cells are more frequently being employed in standard or routine medical treatments. Adult stem cells show a great deal of promising results with over 126,000 treatments in the US alone. Further research may also help alleviate the problem of the shortage of donated organs such as kidneys.

 Figure 2. Shows work done in China on ears using 3D printing of stem cell-based formulas.

 Figure 2. Shows work done in China on ears using 3D printing of stem cell-based formulas.

Successful 3-D printing of ears to replace missing or damaged tissues was reported in 2014. 3D printing is very promising for more complex body parts. In the UK at University College in London, Professor Alex Selfalian and his colleagues have been engineering and developing exact copies of the patient’s ear as shown above. They use 3D scanning and printing technology. Animal studies have been encouraging. This technology is about to undergo its first actual test within the human body; however, China is ahead of other nations by at least 3 years. Within the next few months, the very first clinical trial of its kind will see a dozen ear transplants performed on children in India. Trials are also expected to begin in the UK next year.

Figure 3. Shows 3D printed ear implanted into rat.

Figure 3. Shows 3D printed ear implanted into rat.

The way the procedure will work is quite amazing. First, a 3D scanner will scan the normal ear of the patient. Inside the computer program, the scan will be inverted and turned into a 3D printable model. The researchers will then 3D-print the ear out of a spongy, plastic-like material that is porous and will act as a scaffold. The ear will then be placed under the skin on the forearm of the patient for between 4 and 8 weeks. Over this time, the forearm skin will grow around the scaffold, along with the necessary blood vessels. The ear is then removed from the arm, and transplanted to the patient’s head.

“This is going to revolutionize organ transplantation,” Dr Michelle Griffin, a surgeon at University College Hospital, told the BBC’s Inside Out program. “When children are born without ears or congenital deformities of the ear they have to go through quite invasive surgery. The new method will be less expensive and better.”

Figure 4. Shows open source Biolab using 3D bioprinting platform with earlobe vasculature system.

Figure 4. Shows open source Biolab using 3D bioprinting platform with earlobe vasculature system.

Figure 5. China is conducting clinical trials on various methods to replace ears lost to accidents or disease.

Figure 5. China is conducting clinical trials on various methods to replace ears lost to accidents or disease.

Figure 6. 3D printing of synthetic kidney and prostate computer models for clinical trials

Figure 6. 3D printing of synthetic kidney and prostate computer models for clinical trials.

Dr. Anthony Atala is the director at Wake Forest University Institute for Regenerative Medicine. Dr. Atala is formerly a surgeon and urologist at Harvard University. He is also co-founder of Regenerative Medicine Institute in the hopes of catalyzing the rapid development of a new specialty. The ultimate objective of regenerative medicine is to create body parts using methods such as molds, scaffolding, and 3D printing to replace parts lost to trauma, disease, and age. Several of these methods are now being pursued by startup companies as well as many research centers around the globe.

Researchers and physicians at Wake Forest, other US institutions, Asia, and in Europe have implanted some of the early laboratory-constructed human body parts including windpipes, bladders, urethras, ears, and noses.

Research teams learned they could grow mesenchymal stem cells, a type of stem cell normally found in bone marrow, from skin samples, by subjecting normal cells extracted from the patient to a shock such as bathing in a mildly acidic pH or by genetic manipulation. These induced stem cells can then be converted to body parts when stimulated with hormones and growth factors to coax the stem cells into becoming fat, muscle, and bone cells. These newly-differentiated cells are used to grow sheets of cells of one type such as epithelial or muscle or cartilage.

Expected to be perfected soon are body parts such as synthetic corneas, heart valves, skin, cartilage, lost digits, muscles, and later more complex organs such as kidneys, livers, and whole human hearts.

It takes about seven weeks to grow enough new tissue to make a human bladder. When the tissue is engineered, scientists wrap it around a bladder-sized support made from fine fibers of a collagen-like substitute. The outside of this scaffolding is wrapped with a layer of muscle, while the inner cavity is lined with the sheet of epithelial cells. The new bladder is inflated and deflated repeatedly while being bathed in nutrient fluid at about 37 degrees Centigrade (body temperature). Before the bladder is installed in the patient, to insure adequate oxygen-carrying blood, researchers use a blood vessel-rich segment of membrane, which may be extracted from either the intestinal or abdominal wall.

The artificial support is replaced with the natural matrix over about one year. The new organ or body component is now the same as a healthy human bladder. Over two hundred patients have received new bladders and similar body parts grown this way. The current success rate is over 80%.

Despite the limited funding, the US is making progress in this field; however, other countries have leapfrogged over the USA. For example, China and India have actively entered the market.

In 2018, China published results of its synthetic ear project and is continuing their clinical trials on ears. Global progress is changing medicine forever.


Dr. Levin

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Dr. Levin was born and grew up in Vermont with many winters spent in Florida as a child. As a teenager he wrote poetry, served as a lifeguard and played football. He currently enjoys sailing, exploring underwater caves, snorkeling, writing science fiction and other pursuits. After working on the Apollo and Mars projects, he returned to school to study under Nobel Laureate Paul Dirac, obtaining his PhD in 2.5 years. Dr. Levin founded two companies and served the science policy apparatus in President Ford’s administration. He has been published over 44 times in scientific literature and was awarded over 32 US patents. The science fiction writer is now emerging with his first work, a trilogy entitled 30th Century. The first award-winning book, 30th Century: Escape, is currently available on Amazon. Book two in the series, 30th Century: Revived, will be out in April 2018.

2018-12-10T22:06:28+00:00 April 17th, 2018|Blog, Human physiology|