Live forever! Can science deliver immortality?
In 1912, the year he won the Nobel Prize in Physiology or Medicine for his breakthroughs into sutures and vascular surgery, medical biologist Alexis Carrel started a tissue culture of fibroblast cells from the heart of a chicken embryo. He placed the muscle cells in a stoppered flask and had lab assistants replenish the culture medium regularly. The culture proliferated, as he expected it would. Regularly nurtured with fresh poultry extract, the cells stayed alive for another three and a half decades. His findings proved—or so he thought—that cells are naturally immortal. “Death is not necessary,” Carrel wrote, it is “merely a contingent phenomenon.” Soon, he predicted, we would be engineering human tissues from cell clusters and growing replacement organs in vitro. Growing old would be a thing of the past. We, like cells, are meant to live forever.
He was wrong about cells living forever. Fifteen years after Carrel’s death, scientists realized that cells, like us, senesce and then die. But his predictions regarding regenerative medicine may now be getting closer to reality. In recent years, scientists studying tissue engineering managed to print out a fully beating, three-dimensional, two-chamber mouse heart using a modified desktop, ink-jet printer. By filling the ink cartridge with cells, they’ve been able to “publish” functional human kidneys.