From Newsweek: "Luke Masella was born with spina bifida, a birth defect that paralyzed his bladder. By the time he was 10 years old, despite various treatments, his kidneys were failing. Toxins were building up in his blood, and he had lost 25 percent of his body weight. That's when Luke and his parents opted for a radical solution - a brand new bladder. It might sound like science fiction, but growing new organs from scratch has already become reality. In addition to bladders, scientists have engineered new skin, bone, cartilage, corneas, windpipes, arteries, and urethras. Human organs fail for a multitude of reasons; genetic deformities, injuries, and disease can all damage them. Organ transplantation is an option, of course, but it's risky, and too often there aren't enough donated organs to meet the growing need. So 25 years ago, a group of scientists embarked on an audacious quest: the creation of whole new organs. Brothers Joseph and Charles Vacanti at Harvard Medical School and Robert Langer of the Massachusetts Institute of Technology first promoted the idea of 'tissue engineering' or 'regenerative medicine.' The scientists knew that every organ has a 'scaffolding' - a structure that gives it shape - and many different types of cells with different functions. There are millions of cells, all arranged in an exact order. ... After the scaffolding came the hard part, the part that caused most scientists outside the field to predict that growing new organs would fail. Even if you could build a scaffolding and procure the cells to drape onto that scaffolding, then what? Surely no scientist could assemble millions of cells, one by one and each in the right place, as if the organ were a giant jigsaw puzzle." But of course researchers have proven that they can do this, and the field is presently progressing very rapidly.