Wednesday, April 05, 2006

Your Tax Dollars At Work

One objective in transplant sciences is concerned with approximating and culturing the three-dimensional structure of organs in vitro (in the laboratory) so that the organs can be transplanted into people. The cells, of different organs, have an interesting ability in that they will attempt to physically organize themselves in a coherent manner reflecting their normal structure in the organ of their origin. However, the problem in the laboratory is that they need the proper growing conditions, molecular signals, and the ability to orient themselves spatially, in a three-dimensional manner.

You understand - it is usually not enough to simply add cells to an organ that is malfunctioning. For instance, injecting stem cells into the heart, after myocardial infarction, is very inefficient as the stem cells have great difficulty in establishing themselves in damaged or necrotic tissue. Only a few cells, of the hundreds of thousands, will remain viable and then it is doubtful whether they can re-establish healthy tissue.

Organs are made up of different cells types each cell type with its own functions. The different cells types not only have different functions but also like to congregate in their own areas. One strategy has been to provide cells a three-dimensional structure on which to grow. Many materials are being researched but collagen tends to be a favorite substrate.

New work in this area has produced an artificial bladder now being used in clinical experiments. Although science breakthroughs are typically the work of several researchers and many prior years of work, Dr. James J. Yoo and Dr. Anthony Atala seem to be primarily responsible for the bladder. You can read about their work in the New York Times or go to their scientific article in the Lancet medical journal.
Photo by Sam Ogden