Feature: deceptive appearances – engineering cartilage The tiny
area of uncertainty that is inevitably left by circumstantial
evidence – however compelling – poses a dilemma for scientists,
as well as juries. At Guy’s Hospital in London, Dr Eileen
Gentleman believes the gap between what has been proven as
certain and what has to be inferred from contextual clues has
been hampering progress in the field of tissue engineering. For
the past 15 years, researchers have been growing bone and
cartilage in the laboratory. Biological texts show that these
lab-grown tissues have the appearance, texture, and protein and
mineral components of bone and cartilage. But once they are
tested in an animal, these tissues simply don’t behave quite
like the natural tissues they are supposed to replicate. “When I
got into this field, I saw paper after paper in which people
described putting cells in a material like a polymer, creating a
tissue that resembles cartilage, and testing it in an animal,”
says Dr Gentleman. “The results