However, the Columbia group found that mutated motor neurons have a normal lifespan, in the absence of glial cells, while the Harvard group found they died more quickly than wild-type neurons.
The difference may come from the two groups using different sources for their cells or from some other quirk of the experimental design, said Kevin Eggan, Ph.D., who led the Harvard group.
The Columbia team also concluded that mutated glial cells secrete a toxic compound that selectively targets motor neurons through the so-called Bax cell death pathway.
When the mutated glial cells were grown with motor neurons in the presence of a compound -- the membrane-permeant pentapeptide VPMLK -- that blocks the Bax pathway, the researchers found that fewer neurons died.
