DNA-Programmed Synthesis Of Tissues

Figuring out how tissue architecture affects tissue function is hard to do without a way to control that architecture. Zev J. Gartner of the University of California, San Francisco, and coworkers do it via a DNA hybridization method that builds organlike tissues layer-by-layer (Nat. Methods 2015, DOI: 10.1038/nmeth.3553). First, they pattern an array of DNA spots on a glass substrate. Cells labeled with complementary DNA bind to the DNA on the substrate. By alternating the DNA labeling, they build up tissue with various types of cells in controlled locations. When the tissue reaches the desired size, the researchers add liquid synthetic extracellular matrix containing a DNA-cleaving enzyme that releases the tissue from the substrate. The method works with various cell types and allows the researchers to simultaneously control the size, shape, composition, and spatial arrangement of the resulting tissue. The group used the method to study how tissue size, shape, and composition affect the behavior of individual cells and the patterns of tissue growth.