The loss of limbs due either to war or disease is a devastating experience. And while prosthetic alternatives have come a long way in helping people regain their independence, no artificial material or robotic substitute can fully replace the feel and dexterity of your own flesh and blood. Hope, however, is on its way. Thanks to a team of researchers from Massachusetts General Hospital, regrowing human limbs will someday become a common procedure.
Organ regeneration expert Harold Ott and a team of researchers successfully regrew a rat’s forelimb using a technique called decel/recel. Unlike transplants that require a lifetime of immunosuppressant drugs to prevent the host from rejecting the foreign body part, Decel/Recel involves the use of the body’s own cells and tissue to regrow organs, tissue and limbs.
Decel/Recel regrowing what?
The process involves decellularizing organs, or in this case a body part, from a deceased donor. Put simply, the organ or body part in question is stripped down to its simplest structure. Scientists then take this frame and use it as a scaffold by seeding it with cells taken from the receiving patient. These seeded cells use the scaffold to regrow and recreate the original limb with muscle, tissue and nerves native to the recipient, thereby eliminating the need for immunosuppressant drugs.
Remarkably, Ott’s and his team were able to regrow a rat’s forelimb. In addition, they were also able to attach this regrown forelimb to a living rat. Using electrical impulses, the scientists were able to determine that the regrown limb was fully capable of receiving blood flow from the host rat. “[T]he circulation is probably the biggest challenge, and making sure even the tiniest capillaries are successfully lined with endothelial cells so that they don’t collapse and cause clots [is a significant milestone],” says Steve Badylak of the University of Pittsburgh in Pennsylvania. He goes on to explain that “this is really an engineering approach, taking known fundamental principles of biology and applying them as an engineer would.”
Now, before you get your hopes up, or fear how this technology could be applied adversely, successfully regrowing and transplanting organs and body parts is still far from reality. “The hand must be innervated by thousands of nerves to have meaningful function, and that is at this point an insurmountable problem. So although this is a worthy endeavour, it must at this stage remain in the academic arena, not as a clinical scenario,” explains Oskar Aszmann of the Medical University of Vienna in Austria and inventor of a thought-controlled bionic hand. Looks like we’ll just have to wait a few more decades for the benefits to be had in regrowing organs and body parts.