There is no doubt that science has made many incredible breakthroughs in the last 100 years. This is especially true for medicine and bioengineering. From saving vaccines to revolutionary surgical operations, science improves the quality of our lives. To come up with new solutions to age-old problems, scientists need progress. Behind every medical discovery is a laboratory full of amazing ideas. Sometimes these experiments raise ethical issues. But more often they only lead to interesting solutions to intrusive problems.
What solution can be more sophisticated than growing something in the laboratory from scratch? Here is a list of ten incredible lab-grown pieces collected by the Listverse. This you have not seen!
In 2016, US scientists successfully implanted the bones created in the laboratory by fourteen adult mini-pigs of Yucatan. None of the pigs tore off new organs after surgery. Quite the opposite. The blood vessels of bones grown in the laboratory were seamlessly integrated into the already existing system of swine circulation.
How did this become possible at all?
At first scientists scanned the jawbones of pigs and made maps of their structures. Then they created suitable cell forests from cow bones. Stem cells from pigs were introduced into these structures and filled with a nutrient rich solution. The result was a fully functional living bone.
The rat's limb
Scientists from Massachusetts Hospital were on the front pages of newspapers when in 2015 they raised a whole front paw of a rat in the laboratory. This was the first successful project of its kind in the world.
Dr. Harold Ott led the process, also headed the Laboratory of Engineering and Organ Regeneration Ott. In just 16 days, their experiment led to the creation of muscle tissue. That's how they did it.
Dr. Ott and his team took a living rat limb and removed all of its cells. This process is called decellularization. Once the living cells were removed, the scientists remained one on one with a protein frame for the limb.
Then they filled this structure with living cells that formed muscle tissue and blood cells in just a few weeks. To test the functionality of the limb grown in the laboratory, the group applied a weak electric current to the muscle tissue.
The result? The muscles in the limbs were reduced in the same way as if they were normal, grown in organs.
The first burger, bred under the code name "shmyaso" (schmeat), appeared in London in 2013. It was created in the Netherlands by Dr. Mark Post, professor of vascular physiology. His goal was to reproduce meat that "does not cause animal suffering and does not harm the environment", unlike traditional sources of meat. The project took 5 years and 325,000 dollars.
It was after the success of the Post that the excitement about the creation of laboratory meat began. Memphis Mear, a start-up from San Francisco, created laboratory mitbols in 2016. He also raised chicken sticks – the first in the world.
Nevertheless, it is unlikely that meat grown in the laboratory will be available to the general public until 2021.
A group of scientists from Spain and La Hoya, California, at the Salk Institute successfully cultivated human cells in a pig embryo. The aim of the study was to eventually grow whole human organs that will be used for transplantation, inside other animals. Scientists from Salk have already grown several rat organs inside mouse embryos. But with the latest research, inevitable ethical questions were raised.
In 2015, the United States stopped funding the study of interspecific chimeras for taxpayers' money. In chimera genetics, it is a natural phenomenon when one organism has two or more different sets of DNA.
But the interspecific chimera contains DNA of two or more species. This raises concerns about whether pigs or other animals implanted in human cells will develop the functions of the human brain.
Juan Carlos Izpospuia Belmonte and his team stated that they are aimed to "test the possibility of focusing on human cells when creating certain tissues, while avoiding any contribution to the brain, sperm or ovum."
In 2016, scientists from the Institute of Zoology of the Chinese Academy of Sciences created viable mouse sperm from stem cells. To do this, they extracted stem cells from mice and injected them into testicular cells of newborn mice.
Qi Zhou and Xiao-Yang Zhao, who conducted the experiment, also subjected stem cells to several chemicals involved in the development of spermatozoa. Among them were testosterone, a hormone that causes the growth of the follicle, and the growth-causing hormone from the pituitary.
Two weeks later, scientists received fully functional sperm cells. They implanted this sperm into a living egg and passed the zygote to the female mice. During the experiment, nine mice were born, some of them continued their own offspring. Although this insemination process was not as effective as artificial insemination using natural semen (3% success vs. 9%), this study gives great hope for future infertility treatment.
Blood stem cells
Two different teams of scientists have developed an innovative approach to creating blood stem cells. One group was from the Boston Children's Hospital under the direction of George Daley. They started from human skin cells and "reprogrammed" them to make them become induced pluripotent stem cells. The IPS-cell is the artificially created universal stem cell.
Next, the Daley team injected transcription factors into the IPS cells, which are genes designed to control other genes. After this, the modified IPS cells were implanted in mice for further development. (If you remember, this made those mice interspecies chimeras).
After 12 weeks, these scientists created only a precursor of blood stem cells. But the second team managed to go further.
Weil Cornell's Medical College Shahin Rafiy and his team missed the creation of the IPS. Instead, they took the cells from the blood vessels in adult mice and injected them with four transcription factors. Then they moved the cells to petri dishes, equipped to recreate the human blood vessel environment.
These cells were transformed into blood stem cells. The stem cells from this experiment were so powerful that they completely cured a group of mice suffering from a low number of blood cells due to radiation therapy.
In 2016, Canadian biophysicist Andrew Pelling and his team from the University of Ottawa successfully cultivated human tissues using apples. With the help of the method of decellularization, they removed the existing cells in the apple and stayed with cellular "forests". However, it is this cellulose that gives apples their juicy crunch.
Pelling and his team cut out a piece of apple in the shape of an ear and inserted into it human cells. Cells filled the structure and created an ear concha (outer part of the ear).
Why did you need this experiment? To create cheaper implants. According to Pelling, with his laboratory material there is also less fuss than with conventional biological materials, which are often taken from animals or dead bodies. His method is also not limited to apples. He tries to reproduce his creations on petals of flowers and other vegetables.
The penis of a rabbit
In 2008, Dr. Anthony Atala of Wake Forest Institute of Restorative Medicine made a group of rabbits mate. But it was not an ordinary group of rabbits. All males had penises grown in the laboratory. This idea Atal nurtured and developed since 1992.
Of all the 12 penises created in the laboratory, all allowed the rabbits to mate. Eight rabbits successfully ejaculated, and four – had offspring.
By 2014, Atala and his team created six human penises with the hope of gaining FDA approval for a transplant to humans. The scientists subjected the organs grown in the laboratory to thorough tests using a machine that stretched and squeezed them to make sure that they would withstand the daily load.
A group of scientists also set up machines to pump fluids to organs and lead to an erection. As of 2017, the transplantation of these organs to people has not yet received approval, but is still ahead.
Dr. Anthony Atala and his team also grew human vaginas in their laboratory. These organs were then implanted in four teenagers in Mexico, who, as a result of a rare deviation, were born without them.
To create these organs, the Atala team took a small sample of skin from each girl. Then they created biodegradable forests and introduced into them cells grown on the basis of tissue samples.
The first of these operations was conducted in 2005. Subsequent follow-up of women did not reveal long-term complications caused by the operation. All four women reported normal sexual functioning. However, only two women have uterus. It is unclear whether the other two will be able to bear children.
Sergiu Pasca from Stanford University grew a mini-brain for two years. Scientists call it a cerebral organoid. Being only 4 millimeters in diameter, this small lump of human brain tissue was grown in a laboratory of stem cells. Taking the necessary hormones, scientists were able to force the tissue to grow into a structure that almost completely mimics the parts of the brain.
And do you know what was the biggest difference between the usual part and its miniature version?
The brain grown in the laboratory did not have blood vessels or white blood cells and did not follow the typical stages of neurological development. Instead, they ceased to ripen in the equivalent of the first trimester of human development.
The brain has non-neuronal cells called astrocytes, which reach full maturity in laboratory organelles. Astrocytes are auxiliary cells that create and reduce the connections between neurons as needed. They also create connections with the blood vessels leading to and from the brain and play an important role in the perception of injuries.