Nearly 4,000 Americans are currently waiting for a new heart, but, sadly, only 2,500 will have the chance to get heart transplantation in the next year. Afterwards, the life of many of them will depend on the capability of their body to accept the new installation. Unfortunately, it’s not a rare situation when the body starts developing a massive immune reaction against the new cells and the patients’ body rejects the new heart. To battle this situation, a team of scientists from Massachusetts General Hospital and Harvard Medical School is working on developing a synthetic organ from patients’ own cells. They published their study recently in the journal Circulation Research, explaining how the usage of the patients own skin cells are used to regenerate the heart tissue.
It is a very complicated goal to achieve, because every human heart has its own architecture. In ideal conditions, the scientists could grow hearts from patients own tissues, but there are many things to be done before this can be turned into reality. So, it would be easier for scientists to grow them in the lab, if they had a scaffolding on which the cells can build, like when you build a house and you have the frames already constructed. But, as we noted before, every heart has its own structure, so this makes things way more difficult.
Previously, the researchers applied the technique to mouse hearts. Using a detergent they stripped off the cells of the donor heart that had a big chance to set off an immune response reaction in the recipient. For this particular study, they applied the technique on human hearts. Unsuitable cells were stripped away from 73 donor hearts that were deemed unfit for transplantation. After the cells were cleaned, a new technique with messenger RNA was used to turn them into pluripotent stem cells. Those cells can become any specified cell of the human body, and for this study, the researchers induced them to become two different types of cardiac cells.
Afterwards, researchers must make sure that the remaining matrix could provide a solid base for new cells. If so, they put the induced cells into them. Further on, in a period of two weeks, the hearts are being infused with a nutrient solution and researchers create similar conditions as the ones in our bodies for the heart to grow. At the end, they got a well-structured tissue, very similar to an immature heart. Now all they need is a shock of electricity so it can start beating.
Although this isn’t the first time heart tissue was grown in lab conditions, this is the closest time researchers achieved their goal: Growing an entire working human heart from scratch. But, they are not completely ready to start applying the technique. There are lots of other things that are needed to be done. The improved versions include things like: creating perfect body-like conditions to grow the hearts, improve their yield of pluripotent stem cells(a whole heart would take tens of billions, one researcher said in a press release) and finding ways to help the cells mature more quickly. Finally, they could be able to eliminate the most common side effect in the process of transplantation – rejection of the new heart, through growing hearts by the preferences of each individual.
Via Popular Science.