A multidisciplinary team from Worcester Polytechnic Institute (WPI), the University of Wisconsin-Madison and Arkansas State University-Jonesboro have successfully grown beating human heart cells in a decellularized spinach leaf.

Their success, described in a paper published in the journal Biomaterials, showed the potential of multiple spinach leaves to grow layers of healthy heart muscles that can be used to treat heart attack patients.

"I had done decellularization work on human hearts before and when I looked at the spinach leaf its stem reminded me of an aorta. So I thought, let's perfuse right through the stem," said Joshua Gerslak, a graduate student at WPI and first author of the study, in a press release. "We weren't sure it would work, but it turned out to be pretty easy and replicable. It's working in many other plants."

For their experiment, the researchers first decellularized spinach leaves by washing away plant cells with fluids and microbeads (the size of human blood cells) through the leaf's vasculature. Washing away the plant cells could leave a framework made primarily of cellulose, a natural substance that is not harmful to people.

Cellulose is known for biocompatibility and has been widely used in a variety of regenerative medicine application, including wound healing, bone tissue engineering and cartilage tissue engineering.

After washing away the plant cells, the researchers then seeded the spinach veins with human cells that line blood vessels. The human cells adhered to the plant scaffold and demonstrated contractile function and calcium handling capabilities over the course of 21 days.

Aside from spinach leaves, the researchers were able to remove plant cells from parsley, sweet wormwood and peanut hairy roots

Due to the success of their decellularization technique, the researchers believe that many plant species could be utilize for specialized tissue regeneration studies. For example, spinach leaves might be used a highly-vascularized tissue like cardiac tissue, while cylindrical hollow structure of the stem of jewel weed might be better be used for an arterial graft.