Johns Hopkins Medicine

Stories

Scientists identify claudin-4 as receptor for colon cancer-linked bacterial toxin

Publicized the findings

In 2009, researchers showed that a toxin made by Bacteroides fragilis causes colon tumors in mice. For nearly two decades, no one knew which protein on the surface of colon cells the toxin grabbed to do it.

Updated Oct 31

Studies find brain cell axons are strings of pearls, not smooth tubes

New Capabilities

As of September 2026: Lead research institution behind both studies

Textbook diagrams have drawn brain cells with smooth, tube-like extensions for more than a century. Researchers at Johns Hopkins University found that many of those extensions actually resemble strings of tiny pearls, with repeating bulges that change size as neurons fire.

Updated Sep 17