Posted on Mar 29, 2017, 6 a.m.
Researchers have cultured beating human heart cells on spinach leaves that were stripped of plant cells.
Research teams from Worcester Polytechnic Institute (WPI), the University of Wisconsin-Madison, and Arkansas State University-Jonesboro are trying to take human tissue generation to a new level to treat disease and serious injuries. The hope is to soon generate working tissue, organs, and bones to implant into patients. The main problem is how to efficiently deliver oxygen and nutrients deep into developing tissue. Current technology like 3D printing has not yet matured to do this, so researchers are trying to solve this problem by decellularizing plants and using the plants scaffolding to grow human tissue on. This new technology could unlock a new branch of bioengineering. In addition to the University researchers, specialists in plant biology and human stem cell research joined in on the project. This interdisciplinary research is expected to deliver novel solutions.
Cardiac Tissue Grown on Spinach Leaves
Decellularized plants could be the answer to solving a host of limitations that tissue engineering has had to face in the past, and there are abundant plant species to choose from. The team of researchers conducted a series of experiments on decellularized spinach leaves stripped of all the cells leaving just the scaffolding. They were able to get fluids flowing through the plant's network of vessels and seeded the scaffold with functioning human heart cells. The hope is to use this technique to build layers of new heart tissue for heart patients.
Using spinach leaves, the researchers designed a technique called perfusing using a solution of detergents which is pressed through the veins of the leaves. The acidic solution dissolves the cells of the leaf leaving behind the scaffolding made of cellulose which is biocompatible with humans. This method has been used successfully before in regenerative applications to grow bone and cartilage tissue.
Plants Could Generate Arteries and Bone Tissues
The team of researchers are also experimenting on other plant species and expect successful results. The spinach leaf is unique for heart-cell generation applications because of the intricate network of vessels that mimic cardiac tissue. But other plants with hollow cylindrical tubes could be used to graft arteries or even generate bone tissue.
Tissue generation using plants may prove to be very cost-effective and environmentally friendly. Compared to the limitations and higher cost of composite or synthetic materials, plants are a sustainable source of scaffolding for tissue engineering. Research is continuing with the goal of optimizing the process of plant decellularization. Further research is needed to determine how different human tissues cells will grow and how they will be nourished on the scaffold of various plants. Finally, work is continuing on improving the vascular network necessary for the flow of blood in the human tissue.
Joshua R. Gershlak, Sarah Hernandez, Gianluca Fontana, Luke R. Perreault, Katrina J. Hansen, Sara A. Larson, Bernard Y.K. Binder, David M. Dolivo, Tianhong Yang, Tanja Dominko, Marsha W. Rolle, Pamela J. Weathers, Fabricio Medina-Bolivar, Carole L. Cramer, William L. Murphy, Glenn R. Gaudette. Crossing kingdoms: Using decellularized plants as perfusable tissue engineering scaffolds. Biomaterials, 2017; 125: 13 DOI: 10.1016/j.biomaterials.2017.02.011