Customized Stem Cells

The discovery late last year of a way to generate stem cells from adult skin cells could allow scientists to study disease in unprece­dented detail, from earliest inception to final biochemi­cal demise. That’s because the stem cells could be used to develop cell lines derived from people with a given disease–neurons from Alzheimer’s patients, for example, or blood cells from people with sickle-cell ­anemia. The resulting trove of cells would capture all the genetic quirks of these complex diseases.

By comparing the development and behavior of cells derived from healthy and diseased people, scientists could determine how disease unfolds at a cellular level, identifying points in the process where intervention might do some good. They could also use the cells to test drugs that might correct biochemical abnormalities. “We want to use these cells to ask and answer questions that can’t be asked and answered any other way,” says M. ­William Lensch, a scientist at the Harvard Stem Cell Institute.

Lensch and collaborators in George Daley’s lab at Children’s Hospital in Boston are attempting to create stem-cell lines using tissue samples collected from people with Huntington’s disease, sickle-cell anemia, and another blood disease called Fanconi anemia. Other scientists are expected to follow suit, investigating other diseases.

Credit: Tami Tolpa

1. A biopsy extracts skin cells from an Alzheimer’s patient.

2. Scientists use viruses to insert four genes–normally expressed in developing embryos–into the cells.

3. These genes manage to reprogram some of the cells to turn into colonies of ­embryonic stem cells.

4. Exposure to ­specific chemicals then coaxes the cells to grown into neurons.