Researchers at the University of Rochester said that they have found links between environmental toxins and weakened immune systems that get passed down from generation to generation.
Paige Lawrence, who runs a lab in the environmental medicine department at the University of Rochester, said the results of the study, published this month in the journal iScience, could help explain why some people are more vulnerable to the flu than others.
The project started with mice.
“We got mice, we let them get pregnant, and while they were pregnant, we exposed them to very teeny tiny amounts of dioxins -- one part per billion,” Lawrence said.
Dioxins are a type of pollution that is toxic to both people and mice. Their negative effects on immune systems are well-documented.
What has been less clear is whether those effects can be inherited.
To study that connection, the researchers also had a set of mice that they did not expose to dioxins. They tracked both groups for three generations -- until they had what Lawrence called, “the mouse equivalent of great-grandchildren.”
Then, they exposed both groups of great-grand mice to the flu virus.
Lawrence said the descendants of the mice exposed to dioxin got a lot sicker than the mice whose great-grandparents were not exposed to the chemical -- though males in one generation did not seem to show those same effects. She said these findings can help explain why some people suffer through flu season while others remain unaffected by the virus.
She acknowledged that the results don’t map directly from mice to humans, but Lawrence said there are some strong parallels in our immune systems.
“The little army of cells that we make when we have an infection, they’re very similar in mice and people,” she said. “They share similar molecules that regulate how those cells get activated and how they go out and do their job.”
Lawrence said she hopes her research will encourage policymakers to consider future generations when they set rules around pollution standards today.
“When we think about health and about the environment, we have to think long-term about how what we’re exposed to influences our health potentially for many years and across generations,” Lawrence said.
