The human relationship with microbial life is complicated.
At almost any supermarket, you can pick up both antibacterial soap and
probiotic yogurt during the same shopping trip. Although there are types of
bacteria that can make us sick, Caltech professor of biology and biological
engineering Sarkis Mazmanian and his team are most interested in the thousands
of other bacteria—many already living inside our bodies—that actually keep us
healthy. His past work in mice has shown that restoring populations of
beneficial bacteria can help alleviate the symptoms of inflammatory bowel
disease, multiple sclerosis, and even autism. Now, he and his team have found
that these good bugs might also prepare the immune cells in our blood to fight
infections from harmful bacteria.