3 Dimensional Printing of Living Cells in Hydrogel Layers

An optimized 3D inkjet printing process is demonstrated for structuring alginate into a tissue-like microvasculature capable of supporting physiological flow rates. Optimizing the reaction at the single-droplet level enables wet hydrogel droplets to be stacked, thus overcoming their natural tendancy to spread and coalesce. Live cells can be patterned using this process and it can be extended to a range of other hydrogels. _Advanced Materials

...Thus, it would take just under 2 hours to print a 1 cm thick tissue precursor graft and just over 5 h 30 to print a 3 cm thick kidney precursor. _Advanced Materials PDF

Swiss scientists are using a special inkjet printer to assemble three dimensional living constructs that resemble living tissues. They are still in the early stages of the research, but are achieving some interesting results.

They are working on a technique that should eventually allow them to “print” living constructs resembling human tissues in which cells can develop and interact in a coordinated and physiological manner. Their research results have recently been published in the scientific journal Advanced Materials.

“We have not yet created tissue, strictly speaking,” explains Professor Jürgen Brügger, head of EPFL’s Microsystems 1 Laboratory. “At this stage, we have essentially studied a way in which to structure biological materials in three dimensions; this research will improve cell culture and then will eventually be used as a base for creating tissues.”

...To make up a coherent whole, the cells need an environment that provides the right kinds of signals that induce very specific behavior in each of the cells – proliferation, migration, differentiation or death. In natural tissues, these signals come from molecules that make up a complex extracellular matrix (ECM). By studying the connections and communications taking place between cells and between cells and ECM molecules, the scientists were able to reconstruct this matrix and thus create a new kind of biological ink.

On a technical level, the researchers from EPFL’s two Microsystems Laboratories – under the leadership of professors Jürgen Brugger and Philippe Renaud – focused on developing a gel that could be used as a base from which the tissue could be constructed, as well as a strategy for printing droplets.

...Even though it will still be quite some time before tissue can be constructed, this technology could lead to very promising applications on the medium term. “ An exiting avenue would be to develop 3D constructs that function like human tissues and could be used as models for testing new drugs,” says Lutolf. “This is not only very interesting in a biological sense, but could also reduce the need for animal testing.” _Physorg

Learning to create life-like 3 dimensional cell cultures for research, and learning to create 3-D lab-made living tissues for replacement, are not quite the same things. But the two lines of research are likely to borrow from and contribute to each other, extensively.

Cross-posted from Al Fin Longevity