Baby to Brain

This article was found in Scientific American and tells that researchers found that cells from mice fetuses can migrate into a mother's brain and apparently develop into nervous system cells. Scientists have known for years that fetal cells can enter a mother's blood; in humans, they may remain there at least 27 years after birth. The neurobiologists bred normal female mice with males genetically modified to uniformly express a green fluorescent protein. They found green fetal cells in the mothers' brains. The fetal cells transformed into what seem like neurons, astrocytes , oligodendrocytes, and macrophages. Moreover, after the scientists chemically injured the mouse brains, nearly six times as many fetal cells made their way to damaged areas than elsewhere, suggesting the cells could be responding to molecular distress signals released by the brain. Just how the fetal cells make it through the capillaries separating the brain from the blood system is not known--the cells of the vessels are densely packed, preventing most compounds from crossing the barrier.

The article can be found at
http://www.sciam.com/article.cfm?chanID=sa011&articleID=0001939B-A724-1353-A72483414B7F0000