The difference in plastic quantities surprised him, but his team found another concerning trend, too. Cells in the plaque with lots of plastic showed different gene activity than those with low plastic. In the high-plastic environment, one group of immune cells had switched off a gene that's associated with turning off inflammation. Clark's team also found genetic differences in a group of stem cells thought to help prevent heart attacks and strokes by reducing inflammation and stabilizing plaque. "Could it be that microplastics are somehow altering their gene expression?" Clark said.
Well thats certainly concerning!