Each year, over 4,000 Americans need a heart transplant, but only half of them will get one. And even if they do, there’s a high risk that their body will reject the new heart because their immune system may start a campaign against the alien cells.
That’s the current situation just in the US. Bleak, I know. But that all may change any day now since scientists seem to have found a way to grow functioning hearts in the lab! Most human organs can regenerate their cells after they experience some damage. That’s just how incredible our bodies are! Unfortunately, this doesn’t refer to the heart.
If a person has a heart attack, the dead or damaged heart cells can’t regenerate. Instead, they get replaced with scar tissue. And that’s a serious threat since such scar tissue neither transmits electric impulses nor contracts. As a result, the heart fails.
That’s why it’s crucial to find a solution to the problem of heart transplants, and scientists are so close to saving the day! In 2015, a group of researchers from Harvard Medical School and Massachusetts General Hospital announced that they’d figured out how to deal with the issue of organ shortage.
Besides that, they’d also found a way to reduce the chances that a patient’s body would reject a newly transplanted organ. The answer lies in human skin cells, which can regenerate human heart tissue. Did you catch that? Heart cells from the skin! The researchers followed the technique based on a detergent solution.
To really simplify an incredibly complex procedure, they basically rid a donor heart of the cells that could potentially start an unwanted immune reaction. Remember, it’s because of this immune rejection that a patient’s body doesn’t accept a transplanted organ.
The researchers tested this method on 73 donor hearts. The organs weren’t suitable for transplantation and, therefore, could be used for research purposes. First of all, the scientists stripped the hearts of part of their cells. After that, they used an innovative technique to turn adult skin cells into special stem cells that were capable of creating different cell types.
And since they could potentially become any kind of cell, the researchers turned them into two types of heart tissue. The next step was to make sure that these versatile cells didn’t get rejected by the rest of the heart. For the following two weeks, the hearts covered with the new cells stayed in a nutrient solution.
On top of that, the researchers put the developing heart under the same conditions it would be in once inside the body. As a result, in two weeks, the scientists got hearts with well-developed structure and tissue. They looked exactly like any other immature human heart. And most importantly, after the scientists gave a shock of electricity to the organs (are you ready for this?), they started to beat! Naturally, the final goal of this research is to grow a full-scale human heart.
Unfortunately, up to this point, scientists haven’t managed to develop a working heart from a patient’s own tissues. Remember, the hearts used in this experiment were given to the researchers because they couldn’t be transplanted. Plus, there are some other issues surrounding the structure of the heart that scientists still need to perfect.
But the fact of the matter is that this organ can be successfully grown in the lab. There, the cells can develop inside a special structure. The researchers do currently have a plan that will help them achieve their aim. They want to increase the number of versatile stem cells. After all, a real full-scale heart will need tens of billions of them.
Next, the scientists will try to find out how to make these cells mature faster because time is of the essence when it comes to needing an organ transplant. And the final step will be to improve the body-like conditions in which the hearts will grow. The researchers are sure that this approach will help them grow customized hearts. If it works, patients won’t have to worry about their bodies rejecting their own heart.
And that, Bright Siders, is incredible news! However, the heart isn’t the only organ to be grown in the lab. Scientists have already successfully cultivated several structures of the human body. On top of that, they’ve worked out how to grow “organoids,” which are itsy-bitsy human organs.
For example, scientists from the Ohio State University have grown a tiny brain about the size of a pencil eraser. This organoid is genetically similar to the brain of a 5-week-old fetus. Believe it or not, all of its neurons function correctly and everything! In 2013, a group of Australian scientists from Murdoch Children’s Research Institute and the University of Queensland cultivated a mini-kidney from stem cells.
Their first organoid, which was grown in a Petri dish, contained just two types of cells. But the most recent attempt was more successful. The scientists developed an organ similar to a normal human kidney. It contained all types of kidney cells.
Researchers hope that such organoids can help in cell therapy, disease modeling, and drug testing. That same year, scientists at New York’s Weill Cornell Medical College managed to 3D-print human ears for the first time! They started by making a model of a child’s ear and then sent it to a 3D printer.
After that, they covered the frame with living cells, and the cells grew around this model. Within just 3 months, the ear had developed its own cartilage! A tiny human stomach about 0.1 inches in diameter took just a month to grow in a Petri dish. The lab-grown mini-stomach looks astonishingly similar to the real thing. Dr. James M. Well from Cincinnati Children’s Hospital Medical Center is sure that one day, these mini-stomachs will help scientists understand the complex processes going on in the human stomach.
By studying it, researchers can figure out how the stomach develops or what diseases can strike it. Besides, it’ll get much easier to understand the effects gastric diseases caused by different bacteria can have on this organ. Researchers from several universities collaborated and grew 3D mini-lungs. These organoids had both well-developed airway structures and lung sacks. The lungs functioned for over 3 months.
According to the study’s lead-scientist, Dr. Jason R. Spence from the University of Michigan, the mini-lungs mimicked the real tissues’ responses. It means that with their help, researchers can examine the changes that happen in human lungs when they’re diseased. Besides, the organoids can show how real lungs may react to particular experimental drugs.
The largest internal organ of your body, which is your liver, can repair itself and regenerate tissue…when it’s where it should be, that is. But scientists experienced enormous difficulties every time they tried to cultivate it outside the human body. It was very hard to keep liver cells alive.
But in 2015, researchers from Germany and Israel managed to grow liver cells in the lab. They published their research in the journal Nature Biotechnology. So far, it isn’t a real organ or organoid. But they do believe that the developed cells are the first step to growing an actual full-scale liver. And finally, there’s the food pipe, or “esophagus” if you want to get technical. It connects your throat with your stomach. At 8 inches long, this organ is relatively small.
You probably imagine it like a hollow tube where food slips down like a waterslide, but that’s not the case at all! The muscles of the esophagus have to work hard. They contract to move the food down to your stomach. So, it’s actually a pretty complex organ! But an international team of scientists managed to grow a working food pipe at Kuban State Medical University in Russia.
It took them a mere 3 weeks, and they used (you guessed it) stem cells to pull it off. The newly-grown organ proved its durability after the researchers inflated and deflated it 10,000 times! So, what do you think about growing human organs in the lab?
Credit: Bright Side