If the goal in medicine is to be able to repair people as if they were made out of Legos, then we just took a big stride towards that future. A team at Massachusetts General Hospital has managed to grow a rat’s forearm that, theoretically, could open the door to whole-limb transplants. The team, led by organ regeneration expert Harold Ott used a technique called decel/recel, which has already been used to grow hearts, lungs and kidneys within the confines of a petri dish.
Rather than building a fresh arm, the decel/recel process requires scientists to decellularize organs from deceased donors. As New Scientist describes it, that means washing a forearm from a previously expired rodent until just the “scaffold” remains. It’s a clumsy metaphor, but imagine that you could rinse off the mushy stuff until the biological equivalent of an ice cube tray remains. This empty receptacle retains the structure of the component with none of the icky bits.