Study reveals how Naegleria amoebas navigate tight spaces, shedding light on infection risk

A team led by cell biologist Lillian Fritz-Laylin examined the movement of Naegleria amoebas using narrow glass microchannels, observing that the organisms can pass through openings smaller than their own size and seldom retreat once inside. The study employed N. gruberi, a non-lethal species that mirrors the behavior of its brain-infecting cousin N. fowleri, allowing safe laboratory work. Within the smallest channels, the amoebas maintained forward motion, and in larger passages they moved up to twice as fast as cells outside the channels.

These traits of relentless forward motion and increased speed in confinement may facilitate the pathogen's journey from the nasal cavity to brain tissue when accidental exposure occurs. Although N. fowleri infections are rare in the United States—fewer than ten cases per year—they are typically fatal. The findings, published in the Proceedings of the National Academy of Sciences, aim to improve understanding of how these single-celled organisms locate and invade human hosts. Fritz-Laylin is also a Howard Hughes Medical Institute investigator.