So long, glitter slime. The newest thing in gross arts and crafts is so much better: Researchers have transformed real organ and muscle cells into flexible "tissue paper" that could help surgeons patch wounds and even regrow damaged hearts, ovaries, and lungs. The team described their remarkable creation in the journal Advanced Functional Materials.

Lead author and bioengineer Adam Jakus of Northwestern University hit upon the idea after witnessing a very strange chemical spill in the lab. Jakus had been trying to concoct 3D ink that would allow him to print ovaries. The container of cell-filled fluid overturned, and by the time Jakus reached it, the ink had dried into a flat sheet.

"When I tried to pick it up, it felt strong," Jakus said in a statement. "The light bulb went on in my head. I could do this with other organs."

As Jakus explains in the video below, his first stop was the butcher shop.

The research team made their paper from six kinds of cow or pig tissue: ovary, uterus, kidney, liver, heart, and muscle. The paper contains the scaffolding, or structure, of each tissue type—an encouraging environment in which new, healthy cells can flourish.

And grow they did. Flexible, foldable tissue paper treated with human bone marrow cells became a bustling nursery for the cells. After four weeks, all the original cells had attached and reproduced.

"That’s a good sign that the paper supports human stem cell growth," Jakus said. "It’s an indicator that once we start using tissue paper in animal models it will be biocompatible."

Surgeon and engineer Ramille Shah oversaw the research and was the corresponding author on the journal article. She says the tissue paper has the potential to work as a "very sophisticated Band-Aid" for damaged organs and other parts.

Reproductive scientist Teresa Woodruff tested the paper in her lab as well. She found that paper made with ovarian tissue could be used to grow functional, hormone-producing cells.

"This could provide another option to restore normal hormone function to young cancer patients who often lose their hormone function as a result of chemotherapy and radiation," she said.

Jakus said it's "really amazing" that we could someday turn animal byproducts into life-saving surgical materials. "I'll never look at a steak or pork tenderloin the same way again."