Bioengineers at Harvard and Caltech designed the sponges, which are primarily made from alginate, a gel made from algae. They can be molded into any shape or size and contain large pores, which allow liquids and large molecules to pass through. The pores can also hold cells, proteins and small-molecule drugs, which can then pass into the body when the alginate starts to break down.

 

They could be promising new tissue scaffolds at sites of injury or infection, according to David J. Mooney, a bioengineering professor at Harvard’s School of Engineering and Applied Sciences. They could transplant stem cells, bulk up tissue that’s been lost or degenerated, or even transplant immune cells, Mooney said. Because they can be built to any shape--the team made hearts, stars and squares--they could theoretically be used for any size or shape area in the body.