Considering we can’t live without our hearts, scientists have been experimenting for a very long time how to solve the major bio-engineering problem blocking the regeneration on human tissues and organs.
A group of scientists took out all of the cellular material from the spinach leaves which just left the structure that keeps the cells in place. Then, you have a very thin, flat piece of tissue that already has a vascular network. So in theory, they should be able to stack up multiple leaves and create a piece of cardiac tissue. The major limiting factor for past attempts of solutions to this is lack of vascular network. Techniques alone cannot fabricate microvasculature the way the body needs it (in humans). So the plan is to use the vascular system in spinach leaves to provide the cells that are grown on the leaf nutrients and oxygen. Cardiac muscle is grown on the leaves, which then can be profused with a blood source by the veins inside of the leaf.
I think that everything about this research is absolutely amazing. When you think of a model organism in genetics, it really doesn’t get any better than an abundant plant! Of course plants are different biologically from humans, but the only thing that matters in this case is the vascular network, which the spinach leaves have. If they are successful with this research, it will be very cost effective, ethically sound, and rather quick to create.