How is a mother “connected” to her infant? According to a recent report in Stem Cells, quite literally. The research, conducted on mice, found the stem cells of fetal mice were present in their mothers’ brains. These cells persist long after birth, and even seem to assist in the process of repair when the mother’s brain is damaged.
So how did the researchers identify the fetal cells? They inseminated the mothers with “green mice” who had been genetically altered using jellyfish genes to glow a phosphorescent green. Some of the babies, therefore, were also green mice, and any of their cells entering the mother’s blood stream could be detected.
We found that at least some of the fetal cells that spontaneously enter maternal circulation during pregnancy are capable of entering the maternal brain. Although fetal Green Mouse cells were rare in the brain, the number recovered is not insubstantial. However, although the blood was removed by perfusion, the number of cells identified in brain tissue by the real-time PCR analysis does not reflect only neural cells but also includes cells engrafted into other niches, such as the perivascular environment. Studies of ex-breeder stock females showed that in the intact brain, fetal cells are present at least 2-3 months after pregnancy in some but not all individuals.