LAUSR

Collagen can be 3D-printed to recreate functional components of the human heart. Direct 3D bioprinting of human cells has the long-term goal to generate tissues and organs appropriate for transplant in cases of organ failure. But this has been limited by the ability to support human cells and the surrounding extracellular matrix during the printing process, reducing the ability to generate high-resolution structures. Collagen is the main component of the extracellular matrix, and Adam Feinberg and his colleagues developed a new technique to print collagen that they term freeform reversible embedding of suspended hydrogels (FRESH). Gelation of the collagen is regulated by pH to generate fine structures into which cells can be embedded. They were able to print heart valves, vascular-like networks Credit: Sergii Iaremenko / Science Photo Library / Getty Images and a beating model of a human ventricle using this technique. HS