Science and Technology Daily, Beijing, May 24 (intern reporter Zhang Jiaxin) Scientists at the Institute of Molecular Biotechnology of the Austrian Academy of Sciences have used human pluripotent stem cells to cultivate "mini" heart organoids called "heart-like", which can organize themselves into heart chambers Shaped structure without the need for an experimental stand, which can jump autonomously.
This achievement may completely change the research on cardiovascular disease and congenital heart disease. Related papers were published in the recent "Cell" magazine.
The lack of a good physiological model of the human heart is the main bottleneck hindering people's understanding of heart disease and the development of regenerative therapy.
The previous tissue engineering 3D cardiac organoids have different physiological responses to injury from the human heart and often cannot be used as a good disease model.
In the past decade, the field of self-organizing organoids has brought revolutionary changes to biomedical research.
However, research on heart organoids that can reproduce the process of development and injury response has not been progressed.
Research leader Sasha Mendjan said: “In order for tissues in vitro to be fully physiological, they also need to go through the process of organ formation.” In embryos, organs develop on their own through the process of self-organization. In this process, cell components Interaction, moving around and changing shape as organ structures appear and grow.
This time, the researchers activated all six known signal pathways involved in embryonic heart development in a specific order to induce stem cells to organize themselves.
As the cells differentiate, they begin to form independent layers, similar to the structure of the heart wall.
After a week of development, these organoids form a 3D structure with a closed cavity-equivalent to a 25-day-old heart.
This process is similar to the spontaneous growth trajectory of the human heart.
At this stage, the heart has only one ventricle, which will become the left ventricle of a mature heart.
Organoids are approximately 2 mm in diameter and contain the main cell types common at this stage of development: cardiomyocytes, epithelial cells, fibroblasts, and epicardium.
The research team discovered that this "mini" heart has a clear ventricle that can contract rhythmically to squeeze the fluid in the cavity.
It beats 60 to 100 times per minute, which is the same rate as a heart of the same age and size.
In addition, the research team also tested the response of this heart organ to tissue damage.
They used a cold steel rod to kill some cells of the heart organ to simulate the situation after a heart attack. They found that the heart fibroblasts responsible for wound healing began to migrate to the injured site and produce proteins that repair the damage.
In the future, the research team also plans to cultivate heart organoids with multiple chambers just like the real human heart. Many congenital heart diseases occur when other chambers begin to form, so the multi-chamber model will help doctors better understand how fetal heart defects are formed.