Assembling cells into artificial 3-D tissues, like tiny glands

BERKELEY — As synthetic biologists cram more and more genes into microbes to make genetically engineered organisms produce ever more complex drugs and chemicals, two University of California chemists have gone a step further. A 3-D reconstruction using deconvolution fluorescence microscopy of a single multicellular structure encapsulated in agarose gel. Cells are stained different colors according to the oligonucleotide sequence attached to their surfaces. (Bertozzi lab/UC Berkeley images) They have assembled different types of genetically engineered cells into synthetic microtissues that can perform functions such as secreting and responding to hormones, promising more complex biological capabilities than a single cell alone could produce. "This is like another level of hierarchical complexity for synthetic biology," said coauthor Carolyn Bertozzi, UC Berkeley professor of chemistry and of molecular and cell biology and director of the Molecular Foundry at Lawrence Berkeley National Laboratory. "People used to think of the cell as the fundamental unit. But the truth is that there are collections of cells that can do things that no individual cell could ever be programmed to do.