New Weapons Against Cancer: Millions of Bacteria Programmed to Kill

Genetically modified microbes release “nanobodies” that alert the immune system to cancer in mice, scientists report.


Scientists have used genetically reprogrammed bacteria to destroy tumors in mice. The innovative method one day may lead to cancer therapies that treat the disease more precisely, without the side effects of conventional drugs.

At some point in the future, we will use programmable bacteria for treatment,” said Dr. Dougan, whose research laid some groundwork for the new study. “I think there’s just too much potential.”

Our immune cells can sometimes recognize and destroy cancer cells without assistance. But tumors may hide from the immune system by taking advantage of a gene called CD47.

Normally, the gene makes a protein that studs the surface of red blood cells, a kind of sign that reads, “Don’t Eat Me.” Immune cells see it, and pass by healthy red blood cells.

But as red blood cells age, they lose CD47 proteins. Eventually the immune cells no longer give them a free pass, gobbling up old cells to make way for new ones.