Yes, that's a real human lung pumping away inside a box. Known as the Organ Care System (OCS), this machine helps the tissue to breathe in and out, ensuring that the blood and oxygen continues to flow through the donor organ before it is given to the recipient. Al Jazeera America reports:
The sound of the lungs mechanically breathing was surreal, and we followed these previous organs back to the OR. Once surgeons were ready to make the swap, they held Victoria's old lung and new lung side by side. The difference was night and day. Victoria's old lung was tiny frail and full of ugly black carbon deposits, while her new donor lung was large, pink and fluffy.
You can follow the whole lung transplant story and more details here.